mold cheese experiment

The science behind moldy cheeses: An interview with Dr. Maike Montanhini

By Emanueli Backes

Cheese – a millenary dairy product which plays an essential role in the global economy – is traditionally consumed in many countries and therefore considered one of the most important agriculture products.  In 2019, 26 million tonnes of cheese were produced worldwide – a 2.6% increase on the year before – with a turnover of $114.1 billion 1 . According to the Food and Agriculture Organization (FAO), Europe and North America are the main contributors to worldwide cheese consumption, however, because of its broad texture and flavor variety its consumption reaches many other cultures.  In fact, there has been a significant increase in the number of so-called “cheese-lovers” in regions where the product is not traditionally consumed 2 .

Among the variety of available cheeses, moldy cheeses have unique characteristics, technologically and sensory-wise, that make them special. The history of moldy cheese goes back centuries, and the science behind it is pretty intriguing and charming. Thus, to better clarify this exciting topic and some of its peculiarities, we were pleased to have Dr. Maike Montanhini for a special interview for Science Meets Food. She is a Brazilian dairy technology consultant, researcher, and specialist cheesemaker, with more than 25 years of expertise in the field.

Classes of mold-ripened cheese

If you thought moldy cheese was just a simple cheese group, you might be surprised to discover the immense complexity that goes into making these cheeses. In this interview, Dr. Montanhini highlighted differences between fungal cheeses which are classified into five different categories:

• Cheeses with flowery rind: within this group, there are different types of cheese. The most common are cheeses covered with white fungus ( Penicillium camemberti ), where Brie and Camembert cheese stand out.
• Soft cheese and washed rind (smear-ripened cheese, red-smear cheese, or washed rind): in this type of cheese, the rind is treated during maturation to favor the development of some microorganisms, mainly Brevidobacterium linens , and Geotrichum candidum ; this is a common cheese category in Europe, with Tellegio, Reblochon, and Limburger as examples.
• Blue cheeses: they are cheeses recognized for their appearance and flavor conferred by the development of Penicillium roqueforti within the cheese mass; the most famous examples in this category are Roquefort, Stilton, and Gorgonzola.
• Hybrid cheeses: they are cheeses where the simultaneous development of camemberti fungi on the surface of cheeses and P. roqueforti inside the dough. This fusion of technologies gave rise to Cambozola, Bleu de Bresse, Bavaria Blu, and others.
• Mixed rind cheeses: in this type of cheese, the development of fungi naturally present in cheese, derived from milk and mainly from the environment, is stimulated. In this case, it is not just a fungus species that develop, forming a complex and variable skin depending on the type of cheese. Saint-Nectaire and Tomme de Savoie cheeses are examples of cheeses in this category. Mucor is the predominant genus of fungi present in the rind, which cheeses mushrooms’ flavor and aroma.

Photo by Jackma34 from Pixabay .

The role of fungi

If you are like me, a food science enthusiast, you will probably be pleased to learn the functon of fungi in cheese and what happens in the structure to achieve the final desired product. Helpfully, Dr. Montanhini passed across this point too.

M: Fungi have great proteolytic and lipolytic activity, in addition to other enzymes that act on milk components. As a result, they break down proteins into peptides and amino acids; and lipids into short-chain fatty acids to promote changes in texture, flavor, and aroma.

Cheeses with surface fungi have a centripetal maturation (from the skin to the center), forming a texture gradient: more creamy just below the skin and with a firmer heart in the center. As the cheese matures, this heart decreases until it disappears, while the flavor and aroma intensify. Therefore, these cheeses’ sensory characteristics depend on the degree of ripeness. Young cheeses have a milder, slightly acidic taste, subtle smell, and firm texture. Well-aged cheeses are creamy, with a characteristic flavor and slightly ammoniacal aroma.

On the other hand, blue cheeses have a more homogeneous maturation, with fungi developing inside the dough, forming bluish veins. These cheeses usually have a higher salt content, which plays a selective role in maturing these cheeses, stimulating the growth of P. roqueforti, and inhibiting undesirable contamination. As a result, these cheeses are recognized for their salty taste, spicy flavor, and pronounced aroma, in addition to their white marbled appearance with bluish-green.

In soft cheeses with a washed rind, a complex microbiota develops on the surface, predominantly gram-positive bacteria and yeasts, which leave the cheese with an orange color, characteristic flavor, and intense aroma. The process of washing the rind prevents the cheese from drying out, and the rind from becoming hard; some cheeses in this category have a sticky rind, such as Epoisses.

Photo by Tookapic from Pixabay .

Controlling the fungi in mold-ripened cheese

Globally,  the most recognized categories of moldy cheeses are those with flowery rind and blue cheeses. Dr. Montanhini reinforces that the type of fungus present and applied technology for manufacturing and maturing are crucial for distinguishing them.

M: The differences between these types of cheese are based on the type of fungus present and some stages of the technological processes of manufacturing and maturing them. These fungi can be added in the form of starter culture or be part of the indigenous microbiota present in the milk or environment. Cheeses with white or blue fungus are usually obtained from yeasts’ inoculation in milk or dough before the beginning of maturation.

In blue cheeses, the fungus develops inside the dough. Thus, it is necessary to guarantee the presence of eyes and holes that allow oxygen to enter, contributing to P. roqueforti development. The technological conditions to manufacture and mature should favor the development of the desired fungus and inhibit the growth of those not characteristic of the type of cheese produced. The main control variables are pH, oxide-reduction potential (Eh), salt, and the cheeses’ moisture content. During maturation, the temperature and relative humidity of the chambers must be controlled.

When questioned about the necessary precautions to avoid cheese contamination by other fungi or bacteria, Dr. Montanhini stated some critical remarks.

M: An essential condition for controlling these cheeses’ production is preventing the environmental contamination of the cheese. Spores of unwanted fungi present in the air, water, or equipment can contaminate the cheeses and cause unwanted changes in cheeses where the presence of such fungi is not desired. The primary sources of contamination are brine (which must be treated periodically) and air in the production and maturation environment. Periodic cleaning of the factory’s ventilation systems and spraying antifungal products is recommended to minimize environmental contamination. However, this type of treatment is not suitable for cheeses made with spontaneous natural fungi, as the inoculum comes from the environment itself. It is recommended that sporadic analyses be performed on this type of cheese to ensure no toxigenic fungus is established.

Cheeses’ intrinsic (pH, moisture, Eh, and salt content) and extrinsic (humidity and temperature of the ripening chambers) conditions must be carefully monitored. They are fundamental points to stimulate the growth of the desired fungi that inhibit contaminating fungi through competition.

After all this information, I bet your serving of cheese will never be the same! We are very thankful for having Dr. Montanhini explaining and demystifying a bit more about the science behind moldy cheeses.

[1] Global Trade. Global Cheese Market Hit Record Highs But Is to Lose Momentum Against the Pandemic. 2020. <https://www.globaltrademag.com/global-cheese-market-hit-record-highs-but-is-to-lose-momentum-against-the-pandemic/>

[2] OECD-FAO Agricultural Outlook 2020-2029. 2020. <https://www.cicarne.com.br/wp-content/uploads/2020/07/Outlook-OCDE-FAO-2020-29.pdf>

Emanueli Backes |  Linkedin

SMF Blog Writer

Emanueli is a Brazilian enthusiastic for food science and technologies.  Backes graduated with a degree in Food Engineering and Masters in Quality and Food Safety. She is now pursuing her PhD in Food Science. Backes research focus is on organic synthesis of new antioxidant compounds through enzymatic reactions.

Emanueli loves education and science popularization; she believes everything can be demystified, uncomplicated, and taught.

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Mold Terrarium

What do i need.

A clear container with a lid. (Big glass jars and clear plastic containers work great, but you'll have to throw away the container when you're through, so check with a grown-up about what you can use.)

Adhesive tape

Some leftover food (you can use whatever is in your refrigerator), such as bread, fruit (like oranges, lemons, or grapes), vegetables (like broccoli, zucchini, or green pepper), cheese, and cookies or cake

This Is Important!

DO NOT use anything with meat or fish in it—after a few days, these foods would start to smell very, very bad.

What do I do?

Ask a grown-up for four or five different pieces of leftover food. If the food is small—a grape or one section of an orange—use the whole thing. Cut bigger foods such as bread or cheese into 1-inch chunks.

Dip each piece of food into some water and put it into your container. If you use a big jar, lay it on its side. Try to spread the pieces out so that they are close to each other, but not all in a heap.

Put the lid on the container. Tape around the edge of the lid to seal it.

Put the container in a place where no one will knock it over or throw it away. You may want to label it "Mold Terrarium."

Every day, look at the food in your Mold Terrarium. For the first two or three days, you probably won't see much. But soon you should see blue or green or white fuzzy stuff growing on some of the pieces of food.

After a few more days, some of the food in your mold terrarium may start to rot and look really gross. You can watch how the mold spreads and how things rot for about two weeks. After that, it'll get boring, because not much more will happen.

When you're through with your Mold Terrarium, throw it in the garbage. Don't reuse the container. Don't even open the lid! Mold is not a good thing for some people to smell or breathe.

Here are some things to notice in your mold terrarium:

• What food started getting moldy first?
• What color is the mold? How many different colors do you see?
• What texture is the mold—flat, fuzzy, bumpy?
• Does everything in your Mold Terrarium get moldy?
• Does mold spread from one piece of food to another?
• Do different kinds of mold grow on different types of food?

Wow! I Didn't Know That!

When most foods get moldy, it means they aren't good to eat any more. But some cheeses are eaten only after they become moldy! Blue cheese gets its flavor from the veins of blue-green mold in it. When a blue cheese is formed into a wheel, holes are poked through it with thin skewers. Air gets into these holes, and a very special kind of mold grows there as the cheese ripens.

What's Going On?

What is mold, anyway.

That fuzzy stuff growing on the food in your mold terrarium is mold, a kind of fungus. Mushrooms are one kind of fungus; molds are another.

Unlike plants, molds don't grow from seeds. They grow from tiny spores that float around in the air. When some of these spores fall onto a piece of damp food or other materials, they grow into molds.

Plants contain a chemical compound called chlorophyll. Chlorophyll makes it possible for plants to capture the energy of sunlight and use it to make food (sugars and starches) from air and water. Unlike plants, molds and other fungi have no chlorophyll and can't make their own food. The molds that grow in your mold terrarium feed on the bread, cheese, and other foods. A mold produces chemicals that make the food break down and start to rot. As the food is broken down into small, simple parts, the mold absorbs them and grows.

Ick! Who wants this stuff around?

It can be annoying to find moldy food in your refrigerator. But in nature, mold is a very useful thing. Mold helps food and other materials rot, which is an icky but necessary thing. In a natural environment, rotting things return to the soil, providing nutrients for other living things. Mold is a natural recycler.

Why does the mold on different foods look different?

There are thousands of different kinds of molds. One mold that grows on lemons looks like a blue-green powder. A mold that grows on strawberries is a grayish-white fuzz. A common mold that grows on bread looks like white cottony fuzz at first. If you watch that mold for a few days, it will turn black. The tiny black dots are its spores, which can grow to produce more mold.

Why didn't some foods get moldy?

If you used foods that contain preservatives, mold may not have grown very well on them. If you want to experiment more with mold, you can make one mold terrarium using food with preservatives (like a packaged cupcake) and another using food that doesn't have preservatives (like a slice of homemade cake). Which one grows more mold? You can also experiment with natural preservatives such as vinegar and salt. If you do more experimenting, let us know what you discover!

The Science Behind Your Cheese

The food is not just a tasty snack—it’s an ecosystem

Ute Eberle, Knowable Magazine

There are cheeses with fuzzy rinds such as Camembert, and ones marbled with blue veins such as Cabrales, which ripens for months in mountain caves in northern Spain.

Yet almost all of the world’s thousand-odd kinds of cheese start the same, as a white, rubbery lump of curd.

How do we get from that uniform blandness to this cornucopia? The answer revolves around microbes . Cheese teems with bacteria, yeasts and molds. “More than 100 different microbial species can easily be found in a single cheese type,” says Baltasar Mayo, a senior researcher at the Dairy Research Institute of Asturias in Spain. In other words: Cheese isn’t just a snack, it’s an ecosystem. Every slice contains billions of microbes — and they are what makes cheeses distinctive and delicious.

People have made cheese since the late Stone Age , but only recently have scientists begun to study its microbial nature and learn about the deadly skirmishes, peaceful alliances and beneficial collaborations that happen between the organisms that call cheese home.

To find out what bacteria and fungi are present in cheese and where they come from, scientists sample cheeses from all over the world and extract the DNA they contain. By matching the DNA to genes in existing databases, they can identify which organisms are present in the cheese. “The way we do that is sort of like microbial CSI, you know, when they go out to a crime scene investigation, but in this case we are looking at what microbes are there,” Ben Wolfe, a microbial ecologist at Tufts University, likes to say.

Early on, that search yielded surprises. For example, cheesemakers often add starter cultures of beneficial bacteria to freshly formed curds to help a cheese on its way. Yet when Wolfe’s group and others examined ripened cheeses, they found that the microbial mixes — microbiomes — of the cheeses showed only a passing resemblance to those cultures. Often, more than half of the bacteria present were microbial “strangers” that had not been in the starter culture. Where did they come from?

Many of these microbes turned out to be old acquaintances, but ones we usually know from places other than cheese. Take Brachybacterium , a microbe present in Gruyère, which is more commonly found in soil, seawater and chicken litter (and perhaps even an Etruscan tomb). Or bacteria of the genus Halomonas , which are usually associated with salt ponds and marine environments.

Then there’s Brevibacterium linens , a bacterium that has been identified as a central contributor to the stinkiness of Limburger. When not on cheese, it can often be found in damp areas of our skin such as between our toes. B. linens also adds characteristic notes to the odor of sweat. So when we say that dirty feet smell “cheesy,” there’s truth to it: The same organisms are involved. In fact, as Wolfe once pointed out , the bacteria and fungi on feet and cheese “look pretty much the same.” (An artist in Ireland demonstrated this some years ago by culturing cheeses with organisms plucked from people’s bodies.)

Initially, researchers were dumbfounded by how some of these microbes ended up on and in cheese. Yet, as they sampled the environment of cheesemaking facilities, a picture began to emerge. The milk of cows (or goats or sheep) contains some microbes from the get-go. But many more are picked up during the milking and cheesemaking process. Soil bacteria lurking in a stable’s straw bedding might attach themselves to the teats of a cow and end up in the milking pail, for example. Skin bacteria fall into the milk from the hand of the milker or get transferred by the knife that cuts the curd. Other microbes enter the milk from the storage tank or simply drift down off the walls of the dairy facility.

Some microorganisms are probably brought in from surprisingly far away. Wolfe and other researchers now suspect that marine microbes such as Halomonas get to the cheese via the sea salt in the brine that cheesemakers use to wash down their cheeses.

A simple, fresh white cheese like petit-suisse from Normandy might mostly contain microbes of a single species or two. But in long-ripened cheeses such as Roquefort, researchers have detected hundreds of different kinds of bacteria and fungi. In some cheeses, more than 400 different kinds have been found, says Mayo, who has investigated microbial interactions in the cheese ecosystem. Furthermore, by repeatedly testing, scientists have observed that there can be a sequence of microbial settlements whose rise and fall can rival that of empires.

Consider Bethlehem, a raw milk cheese made by Benedictine nuns in the Abbey of Regina Laudis in Connecticut. Between the day it gets made (or “born,” as cheesemakers say) to when it’s fully ripe about a month later, Bethlehem changes from a rubbery, smooth disk to one with a dusty white rind sprouting tiny fungal hair, and eventually to a darkly mottled surface. If you were to look with a strong microscope, you could watch as the initially smooth rind becomes a rugged, pocketed terrain so densely packed with organisms that they form biofilms similar to the microbial mats around bathroom drains. A single gram of rind from a fully ripened cheese might contain a good 10 billion bacteria, yeasts and other fungi.

But the process usually starts simply. Typically, the first microbial settlers in milk are lactic acid bacteria (LABs). These LABs feed on lactose, the sugar in the milk, and as their name implies, they produce acid from it. The increasing acidity causes the milk to sour, making it inhospitable for many other microbes. That includes potential pathogens such as Escherichia coli , says Paul Cotter, a microbiologist at the Teagasc Food Research Centre in Ireland who wrote about the microbiology of cheese and other foods in the 2022 Annual Review of Food Science and Technology .

However, a select few microorganisms can abide this acid environment, among them certain yeasts such as Saccharomyces cerevisiae (baker’s yeast). These microbes move into the souring milk and feed on the lactic acid that LABs produce. In doing so, they neutralize the acidity, eventually allowing other bacteria such as B. linens to join the cheesemaking party.

As the various species settle in, territorial struggles can ensue. A study in 2020 that looked at 55 artisanal Irish cheeses found that almost one in three cheese microbes possessed genes needed to produce “weapons” — chemical compounds that kill off rivals. At this point it isn’t clear if and how many of these genes are switched on, says Cotter, who was involved in the project. (Should these compounds be potent enough, he hopes they might one day become sources for new antibiotics.)

But cheese microbes also cooperate. For example, the Saccharomyces cerevisiae yeasts that eat the lactic acid produced by the LABs return the favor by manufacturing vitamins and other compounds that the LABs need. In a different sort of cooperation, threadlike fungal filaments can act as “roads” for surface bacteria to travel deep into the interior of a cheese, Wolfe’s team has found.

By now you might have started to suspect: Cheese is fundamentally about decomposition. Like microbes on a rotten log in the woods, the bacteria and fungi in cheese break down their environment — in this case, the milk fats and proteins. This makes cheeses creamy and gives them flavor.

Mother Noella Marcellino, a longtime Benedictine cheesemaker at the Abbey of Regina Laudis, put it this way in a 2021 interview with Slow Food: “Cheese shows us what goodness can come from decay. Humans don’t want to look at death, because it means separation and the end of a cycle. But it’s also the start of something new. Decomposition creates this wonderful aroma and taste of cheese while evoking a promise of life beyond death.”

Exactly how the microbes build flavor is still being investigated. “It’s much less understood,” says Mayo. But a few things already stand out. Lactic acid bacteria, for example, produce volatile compounds called acetoin and diacetyl that can also be found in butter and accordingly give cheeses a rich, buttery taste. A yeast called Geotrichum candidum brings forth a blend of alcohols, fatty acids and other compounds that impart the moldy yet fruity aroma characteristic of cheeses such as Brie or Camembert. Then there’s butyric acid, which smells rancid on its own but enriches the aroma of Parmesan, and volatile sulfur compounds whose cooked-cabbage smell blends into the flavor profile of many mold-ripened cheeses like Camembert. “Different strains of microbe can produce different taste components,” says Cotter.

All a cheesemaker does is set the right conditions for the “rot” of the milk. “Different bacteria and fungi thrive at different temperatures and different humidity levels, so every step along the way introduces variety and nuance,” says Julia Pringle, a microbiologist at the artisan Vermont cheesemaker Jasper Hill Farm. If a cheesemaker heats the milk to over 120 degrees Fahrenheit, for example, only heat-loving bacteria like Streptococcus thermophilus will survive — perfect for making cheeses like mozzarella.

Cutting the curd into large chunks means that it will retain a fair amount of moisture, which will lead to a softer cheese like Camembert. On the other hand, small cubes of curd drain better, resulting in a drier curd — something you want for, say, a cheddar.

Storing the young cheese at warmer or cooler temperatures will again encourage some microbes and inhibit others, as does the amount of salt that is added. So when cheesemakers wash their ripening rounds with brine, it not only imparts seasoning but also promotes colonies of salt-loving bacteria like B. linens that promptly create a specific kind of rind: “orangey, a bit sticky, and kind of funky,” says Pringle.

Even the tiniest changes in how a cheese is handled can alter its microbiome, and thus the cheese itself, cheesemakers say. Switch on the air exchanger in the ripening room by mistake so that more oxygen flows around the cheese and suddenly molds will sprout that haven’t been there before.

But surprisingly, as long as the conditions remain the same, the same communities of microbes will show up again and again, researchers have found. Put differently: The same microbes can be found almost everywhere. If a cheesemaker sticks to the recipe for a Camembert — always heats the milk to the relevant temperature, cuts the curd to the right size, ripens the cheese at the appropriate temperature and moisture level — the same species will flourish and an almost identical kind of Camembert will develop, whether it’s on a farm in Normandy, in a cheesemaker’s cave in Vermont or in a steel-clad dairy factory in Wisconsin.

Some cheesemakers had speculated that cheese was like wine, which famously has a terroir — that is, a specific taste that is tied to its geography and is rooted in the vineyard’s microclimate and soil. But apart from subtle nuances, if everything goes well in production, the same cheese type always tastes the same no matter where or when it’s made, says Mayo.

By now, some microbes have been making cheese for people for so long that they have become — in the words of microbiologist Vincent Somerville at the University of Lausanne in Switzerland — “domesticated.” Somerville studies genomic changes in cheese starter cultures used in his country. In Switzerland, cheesemakers traditionally hold back part of the whey from a batch of cheese to use again when making the next one. It’s called backslopping, “and some starter cultures have been continuously backslopped for months, years, and even centuries,” says Somerville. During that time, the backslopped microbes have lost genes that are no longer useful for them in their specialized dairy environment, such as some genes needed to metabolize carbohydrates other than lactose, the only sugar found in milk.

But not only has cheesemaking become tamer over time, it is also cleaner than it used to be — and this has had consequences for its ecosystem. These days, many cows are milked by machines and the milk is siphoned directly into the closed systems of hermetically sealed, ultra-filtered storage tanks, protected from the steady rain of microbes from hay, humans and walls that settled on the milk in more traditional times.

Often the milk is pasteurized, too — that is, briefly heated to high temperatures to kill the bacteria that come naturally with it. Then, they’re replaced with standardized starter cultures.

All of this has made cheesemaking more controlled. But alas, it also means that there’s less diversity of microbes in our cheeses. Many of our cheddars, provolones and Camemberts, once wildly proliferating microbial meadows, have become more like manicured lawns. And because every microbe contributes its own signature mix of chemical compounds to a cheese, less diversity also means less flavor — a big loss.

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Mold Science Fair Project Ideas

Does Mold Grow Faster on Cheese or Bread for a Mold Science ...

Choosing a science fair project can seem hard when you have so many from which to choose. A popular choice for young students involves completing a project on mold. With a little research and help from parents, when needed, mold projects are easy to complete and fun if you have an interest in this sometimes-stinky form of science.

Which Grows Mold The Fastest

For this science project, you set out to answer the question, “Which food will mold grow on faster: bread, milk, bananas or cheese?” While completing the project, you will discover how quickly certain foods spoil and grow mold when you do not properly store them, such as placing them in a refrigerator. FREEScienceFairProject.com recommends keeping all of the foods fresh when you start the experiment and then place them into separate dishes inside of a single cabinet in order to control the temperature affecting the food. You will watch over the food for a number of days, recording the results as you go along until the final food has molded. Then analyze your data and create your final report for the science project, telling which of the four foods grew mold the fastest.

Mold Growth

This project sets out to discover the answer to the question, “What are the best conditions for mold growth?” Place slices of fresh bread into three different conditions—hot and moist, warm and moist, and cold and moist—to see which allows mold to grow. The mold science project, shared by Crystal Clear Science Fair Projects, requires more attention and detail to complete, using items such as a microscope and specimen staining kit to gather the data needed to produce the project's conclusion. Data analyzed at the end of the project includes determining what type of mold grew and which conditions produced the most molds.

Moldy Cheese

For those wishing to embark on a more advanced science project about mold, cheese provides a great opportunity for identifying different molds and determining the differences between them. Students can answer the question, “Is the rate of mold growth affected on cheese by the variety of mold that has grown?” Students should allow a cheese, such as cheddar, to mold, and then extract the mold from the cheese, and the mold from a soft cheese such as blue vein cheese. Then place the mold of two separate pieces of a control cheese (Parmesan, mozzarella) and then observe them for a period of time chosen by the student. The student should note the rate of growth of the two separate molds, whether any new varieties of molds have presented themselves and what effect the molds have had on the cheese.

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• FREEScienceFairProject.com: Mold Experiment

About the Author

A full-time home educator and mother, Paisley Parmer is a Central Florida native. Parmer writes education-related articles with forays into travel and family-related topics. Her work has been published on various websites.

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fromage cheese image by Adam Borkowski from Fotolia.com

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Food For Thought

• For Foodies

The Cheese Does Not Stand Alone: How Fungi And Bacteria Team Up For A Tastier Rind

Menaka Wilhelm

A block of Tomme de Savoie cheese ages with a sweater of Mucor lanceolatus fungal mold. Mucor itself doesn't have a strong taste, but more flavorful bacteria can travel far and wide along its hyphae — the microscopic, branched tendrils that fungi use to bring in nutrients. Benjamin Wolfe/Benjamin Wolfe hide caption

A block of Tomme de Savoie cheese ages with a sweater of Mucor lanceolatus fungal mold. Mucor itself doesn't have a strong taste, but more flavorful bacteria can travel far and wide along its hyphae — the microscopic, branched tendrils that fungi use to bring in nutrients.

It was the tiny streams of slime that stood out.

As a microbiologist who studies the rinds of cheeses like Stilton, Gruyere and Taleggio, Benjamin Wolfe had done plenty of experiments on bacteria, yeast and mold. But he'd never seen anything like this.

He wasn't actually running a lab test when he noticed those slimy streams — he was working with a photographer to document the microbes of a Saint-Nectaire rind. He expected to show the photographer what he normally saw from cheese microbes: fungal molds that branched out in many directions, like a plants' roots, and bacterial colonies camped out in dots and blobs. But there was something else, too: little rivulets running along the branches of a swath of fungus.

Maybe swimming bacteria were creating the streams, but he couldn't be sure. Inspired by the photo shoot, Wolfe, an assistant professor at Tufts University, went back to his cheese rinds with new questions. What, exactly, was traveling along the fungus, and how was it moving?

Microbes cultured from the rind of Saint-Nectaire cheese. The branched hyphae of a fungal mold coexist with the blobs of bacterial colonies. Benjamin Wolfe/Benjamin Wolfe hide caption

Microbes cultured from the rind of Saint-Nectaire cheese. The branched hyphae of a fungal mold coexist with the blobs of bacterial colonies.

He'd read about bacteria moving along fungi in soil. The microscopic, branched tendrils that fungi use to bring in nutrients — their hyphae — functioned as a specialized microbial highway. "Bacteria can swim through liquids, and the fungi, these hyphae, have a thin layer of liquid on the outside of them," Wolfe says. Soil bacteria were known to hop into this lazy river for travel.

In the fungus he saw, even a tiny channel of water outside fungal branches would leave a bacterium plenty of room to swim. But it was also possible that he'd just seen bacteria hitching a ride as the fungus grew, instead of swimming on their own.

So he and his students scraped samples off cheese rinds, and chose microbes for experiments , which they published recently in Nature Communications. They picked a swimming bacteria, and a few molds that grew at different speeds, hoping to see if the bacteria was moving, or if the fungi did all the pushing. One mold grew quickly and spread out wide, like a microbial Los Angeles, while another grew slowly, knitting itself into dense networks, more like a fungal Tokyo.

These are cheese rind microbes, so many bring a special flavor to the table. Their choice of bacteria, Serratia proteamaculans , gives a cheese a nice note of cooked cabbage. The slow-growing fungal mold, a strain of Penicillium , tastes earthy, like mushrooms, with a hint of damp basement, Wolfe says.

Another mold they studied, Galactomyces geotrichum , contributes a strong, unique flavor profile suited for stinky cheese lovers. "The best way to describe it is sweet, buttery flatulence," Wolfe says. He meant that as a compliment.

Sure enough, when Wolfe and his students left bacteria to grow alongside fungal molds, the colonies spread farther than bacteria alone. As the mold branched outward, it seemed, it gave nearby bacteria a boost. And at closer zoom, the bacteria were clearly swimming along the hyphae, just like the streams Wolfe noticed during that first surprising photo shoot.

Fuzzy tufts of Mucor lanceolatus mold are seen next to smaller colonies of Serratia proteamaculans, bacteria which give a cheese a nice note of cooked cabbage. Benjamin Wolfe/Benjamin Wolfe hide caption

Fuzzy tufts of Mucor lanceolatus mold are seen next to smaller colonies of Serratia proteamaculans, bacteria which give a cheese a nice note of cooked cabbage.

From a cheese-making perspective, it's a really nice idea that fungal molds would help bacteria spread out and grow. Both entities imbue their surroundings with different flavors, so their intermingling creates a complex, tasty cheese. But from a microbial standpoint, it doesn't make perfect sense that fungus and bacteria would cooperate.

That's because all these microbes need the same ingredients to survive — water and nutrients — and when resources are scarce, they've got tricks for making sure the competition isn't friendly. Fungal molds create chemicals specialized to burst bacteria open, which we've co-opted for antibiotics like penicillin. Bacteria have specialized enzymes, called chitinases, that liquify fungi, reducing them to a slurpable smoothie of carbon and nitrogen. "People have looked at fungal hyphae and bacteria just as antagonists," says Lukas Wick, a microbiologist at the Helmholtz Centre for Environmental Research. "And this is certainly part of the story, but it's a really complex story."

Despite those unfriendly adaptations, bacteria stand to gain a lot from fungal networks. Fungi pump water and nutrients around their hyphae, so any bacteria along for the ride also has access to those resources."They are a logistic network themselves — it's a type of supply chain," says Wick. For a bacterium, hyphae is the opposite of a lonely state highway that stretches for miles without a gas station or drive-thru in sight.

Colonies of microbes from different cheese rinds. From right to left, Comte, Robiola, blue cheese. Benjamin Wolfe/Benjamin Wolfe hide caption

Not all bacteria can swim, so the fungal network can only take some bacteria so far. And unfortunately, many toxic bacteria can hop onto the hyphae highway. E. coli grows better in foods that contain certain fungi. Listeria , which can infect the cheeses Wolfe studies, is also known to travel via fungal network.

But ideally, as the picture of how specific fungi affect certain bacteria gets clearer, cheese mongers will be able to tweak the microbial communities of their cheese rinds to maximize precise flavors and minimize contamination. One day, cheese makers might cultivate a fungus that deters dangerous bacteria, ferrying only the flavorful microbes along.

• food science
• cheese science

Which Food Will mold the Fastest Science Fair Project?

Unlock the Secrets of Decay: Explore Which Foods Mold the Fastest in this Fascinating Science Fair Project. Discover the Science of Spoilage!

The microscopic life forms called molds, which grow on water and nutrient-rich surfaces, while producing their own food through photosynthesis, are pervasive in our surroundings. They thrive on substances such as sugar, starch, or decayed plant material present in the soil.

Which food will mold the fastest science fair project? The answer is a bread loaf. Bread loaves are known to grow mold quickly because of their shape and moisture content.

He came up with the following hypothesis: Strawberries would mold the most quickly since they don’t have as many preservatives as bread and cheese.

Similarly, which meal will mold the variables the fastest?

Supplies and equipment

• A cabinet in which the samples will be stored for one week.
• Pencil and paper

Second, why is milk the quickest to mold? Milk offers a very suitable environment for the development of microorganisms, resulting in fast mold, yeast, and bacterium growth. Milk is also rapidly chilled to avoid natural sourness and extend the shelf life of the product.

Also, how can you quickly mold something?

To develop mold on bread, gather the following items: a piece of any type of bread, a sealable plastic bag, a spray bottle, and water. Any kind of bread will do, but keep in mind that store-bought sandwich bread includes preservatives and will take longer to mold. Mold will develop quicker on fresh bread.

What causes certain foods to mold more quickly than others?

Processed foods include preservatives that make it more difficult for mold to grow on them, while natural foods do not contain preservatives and mold much more quickly. Mold need both moisture and room to thrive.

Answers to Related Questions

What foods cause mold to grow.

While most molds prefer warmer temperatures, they may also thrive in the refrigerator. Molds are also more tolerant to salt and sugar than other food invaders. Molds may therefore develop in refrigerated jams and jellies, as well as on cured, salty meats such as ham, bacon, salami, and bologna.

What are the dangers of eating moldy foods?

Foods containing mold and yeast:

• All cheese, particularly moldy cheeses like stilton, buttermilk, sour cream, and sour milk products are the worst.
• Beer, wine, cider, whiskey, brandy, gin, and rum are all examples of alcoholic beverages.
• Vinegar and vinegar-containing foods, mayonnaise, pickles, soy sauce, mustard, and relishes are examples of condiments.

What foods deteriorate the most quickly?

20 Foods That Go Bad the Quickest

• Beans, green

Which fruit produces the most research in the shortest amount of time?

Olivia Vanderbeek is a Dutch actress. “Which Fruit Does Mold Grow Fastest on?” was my initial query. My testing revealed that the banana develops mold the quickest, taking 6-7 days, followed by the orange, which takes 7-9 days. The lemon came in third with a 9-day time.

Which burger will be the first to develop mold?

Wendy’s burger was the first to exhibit indications of mold. The Deluxe burger was the third option. A&W and McDonalds were the fourth and fifth burgers, respectively, since they were opened at the same time. Wendy’s burger has the fastest growth rate of all the burgers.

Which kind of bread molds the quickest?

Conclusion. Because brown bread has the fewest preservatives, we believe it will mold the quickest. Brown bread was the bread that molded the quickest.

What is the best way to develop mold on bread for a science project?

Experiment #1 using a Bread Mold:

• Obtain authorization to carry out the experiment.
• A piece of bread should be dipped in water.
• Place the bread in a plastic bag and seal it.
• Close the plastic bag and seal it.
• Close the plastic bag with tape.
• Place a tiny piece of tape in the bag’s corner and write the date on it.

How quickly does mold develop on fruit?

As the spore takes root, it starts to spread and produce additional spores, which spread rapidly on your food’s surface. Molds may take over your food in as little as 12 to 24 hours, while others might take weeks to take over.

What are the ideal conditions for bread mold to grow?

Mold thrives in warm, dark, and damp environments. The sealed bread should grow mold more slowly than the open bread in the first sample. The bread left in the dark should grow mold faster than the bread kept in the light in the second sample.

What happens if you eat stale bread with mold on it?

The simple answer is no, you won’t die from eating mold; it will be digested like any other meal, and as long as your immune system is in good shape, the worst you’ll get is nausea or vomiting from the taste/idea of what you’ve just eaten.

What causes the mold to grow on bread?

Bread mold needs moisture and oxygen to thrive since it is a live creature. The fungus absorbs the moisture contained in the bag and grows at a quicker pace as a result. Bread mold, on the other hand, does not need light to develop since it is a fungus, not a plant.

Mold grows on paper in a variety of ways.

Paper includes cellulose, a kind of organic substance that certain molds use as a food supply. Mold spores are attracted to damp paper or paper in a humid atmosphere because they may grow, feed, and breed on it. Mold spores require temperatures between 32° and 120° F to develop and flourish.

When it comes to mold, how long does it take to grow?

Within 24 to 48 hours

Why is it that cheese molds more quickly than bread?

Experiments with Cheese Molds

Because it’s difficult to regulate the acidity levels in homemade bread and it may include less preservatives, it molds quicker than store-bought bread.

When it comes to mold, where does it develop the fastest?

According to the University of Illinois Extension, mold thrives in warm, humid conditions. Mold development is affected by temperature fluctuations caused by light. When lights are left on to warm the surrounding air in a chilly location with temps below the mid-70s, mold develops quicker.

Is it true that the same molds develop on all kinds of bread?

While various kinds of mold may develop on different types of bread, Penicillium, Alternaria, Aspergillius, Botrytis, Mucor, Fusarium, and Cladosporium are some of the most prevalent food-borne molds. Molds come in a range of hues, including green, white, black, and gray, and may be slimy, fuzzy, or velvety.

What role does temperature have in mold growth?

What Effect Does Temperature Have on Mold Growth? Mold development may be inhibited or encouraged depending on the temperature. Higher temperatures may promote mold development, particularly on food products or wet surfaces caused by condensation caused by high temperatures.

Mold on bread is what color?

Spores may move through the package’s air and germinate on other sections of the bread (1). They’re responsible for the color of mold, which may be white, yellow, green, gray, or black depending on the kind of fungus.

The “ what food item has less mold on it? ” is a question that will be answered by science fair project.

What food will mold the fastest?

Mold will grow on breads, cereals and pasta the fastest.

Which food will mold the fastest science fair project hypothesis?

Which fruit rots the fastest science project.

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Which Cheese Grows Mold the fastest?

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Re: Which Cheese Grows Mold the fastest?

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February 5, 2024

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Scientists 'break the mold' by creating new colors of blue cheese

by University of Nottingham

Experts at the University of Nottingham have discovered how to create different colors of blue cheese. After discovering how the classic blue-green veining is created, a team of experts from the School of Life Sciences, were able to create a variety of different fungal strains that could be used to make cheese with colors ranging from white to yellow-green to red-brown-pink and light and dark blues.

The findings of the study are published in the journal npj Science of Food .

The fungus Penicillium roqueforti is used worldwide in the production of blue-veined cheese such as Stilton, Roquefort and Gorgonzola. Its unique blue-green color and flavor comes from pigmented spores formed by fungal growth. Using a combination of bioinformatics, targeted gene deletions and heterologous gene expression, the research team, led by Dr. Paul Dyer, Professor of Fungal Biology, learned the way in which the blue-green pigment is produced.

The researchers found that a biochemical pathway gradually forms the blue pigments, starting at a white color, which progressively becomes yellow-green, red-brown-pink, dark brown, light blue, and finally dark blue-green. The team were then able to use some classic food safe (non GM) techniques to "block" the pathway at certain points, and so create strains with new colors that can be used in cheese production.

Dr. Dyer said, "We've been interested in cheese fungi for over 10 years and traditionally when you develop mold-ripened cheeses, you get blue cheeses such as Stilton, Roquefort and Gorgonzola which use fixed strains of fungi that are blue-green in color. We wanted to see if we could develop new strains with new flavors and appearances.

"The way we went about that was to induce sexual reproduction in the fungus, so for the first time we were able to generate a wide range of strains which had novel flavors including attractive new mild and intense tastes. We then made new color versions of some of these novel strains."

Once the team produced the cheese with the new color strains, they then used lab diagnostic instruments to see what the flavor might be like.

"We found that the taste was very similar to the original blue strains from which they were derived," said Dr. Dyer. "There were subtle differences but not very much.

"The interesting part was that once we went on to make some cheese, we then did some taste trials with volunteers from across the wider University, and we found that when people were trying the lighter-colored strains they thought they tasted more mild. Whereas they thought the darker strain had a more intense flavor.

"Similarly, with the more reddish brown and a light green one, people thought they had a fruity tangy element to them—whereas according to the lab instruments they were very similar in flavor. This shows that people do perceive taste not only from what they taste but also by what they see."

The team, which included lead postgraduate student Matt Cleere, will now look at working with cheese makers in both Nottinghamshire and Scotland to create the new color variants of blue cheese . A University spin-out company called Myconeos has also already been established to see if the strains can be commercialized.

"Personally, I think it will give people a really satisfying sensorial feeling eating these new cheeses and hopefully might attract some new people into the market," adds Dr. Dyer.

Provided by University of Nottingham

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Science project, how to grow mold.

Grade Level: 8th; Type: Microbiology

Students will discover whether mold grows faster in dry or moist conditions.

Research Questions;

How does mold grow?

Most people think of nasty and negative thoughts about mold. But do you know that some types of mold are beneficial? Take penicillium, for example. It is used to produce penicillin, an ingredient needed to make antibiotics which kills off certain kinds of harmful bacteria in the body. And some molds are even edible.

Prolonged exposure to mold may lead to health and respiratory problems in people in weak immune systems and underlying health problems. Most kinds of mold should pose no danger to a healthy individual, especially when only exposed for a short period of time and/or at tiny amounts. However, some types of mold that are caused by flooding and severe water damage may jeopardize health.

• 3 pieces of expired,stale bread (not moldy yet, but just past the best-by date)
• 3 plates with a cover
• A squishy sponge
• A bathroom (probably the moistest location in the house)
• Labels & markers
• Paper and pencil for notes

Recommended for safety

• safety mask
• rubber gloves

Experimental Procedure:

• Take one piece of bread and place it flat on a plate, cover with a clear lid. Put a label on the lid (without obstructing your view) and label it “A”. This piece should be left in a dry location.
• Dampen a sponge and put it on a plate. Set the 2nd piece of bread on top of it and cover. Leave this plate near the 1st. Label it “B”.
• With the 3rd piece of bread, follow step 1, but instead of placing it at the dry location, take it and place it in the bathroom. Label it as “C”. Please make sure no little hands get to it and no one eats it (but why would anyone...)...!
• Record your observations for the progression of mold growth day by day for at least 1 week or until you observe a sufficient amount of mold. Are there any differences in mold growth and patterns? Be sure to take photos.
• After the experiment, record your results. Which piece of bread had the most mold and/or the fastest growth?
• Properly dispose of the moldy bread after the experiment. Do not consume nor intentionally sniff the mold.

Terms/Concepts: Mold; Fungi

References:

http://www.epa.gov/iedmold1/moldcourse/chapter1/lesson5.html

http://www.cdc.gov/mold/

Madigan M; Martinko J (editors). (2005).  Brock Biology of Microorganisms  (11th ed.). Prentice Hall.  ISBN   0131443291 . OCLC   57001814 .

Ryan KJ; Ray CG (editors) (2004).  Sherris Medical Microbiology  (4th ed.). McGraw Hill. pp. 633–8.  ISBN   0838585299 .

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Factors affecting the the growth of molds or yeast

Introduction: (initial observation).

Molds are varieties of multi-cellular organisms that grow on bread, fruits, cheese and almost any other dead organic matter.

Learning about the factors that affect the growth of mold and yeast can help us to control reproduction of these micro organisms.

This project guide contains information that you need in order to start your project. If you have any questions or need more support about this project, click on the “Ask Question” button on the top of this page to send me a message.

If you are new in doing science project, click on “How to Start” in the main page. There you will find helpful links that describe different types of science projects, scientific method, variables, hypothesis, graph, abstract and all other general basics that you need to know.

Project advisor

What you will see in this project is just an example of information and experiments about growing mold and Yeast. You need to read this information and then come up with your own procedures. First you will decide which one you want to study on. Mold is an easy one, but you may select yeast as well. The next step is growing the organism that you select in order to make yourself familiar with what is involved. In your final step, you will repeat growth experiment at different conditions of light, moisture, and temperature. Finally, you will compare the results and draw a conclusion.

Information Gathering:

Find out about mold, yeast or other types of fungi, how they grow, and where they grow. Read books, magazines or ask professionals who might know in order to learn about different types of fungi. Keep track of where you got your information from.

Click here to see a sample project related to mold growth.

Mold if a fungi. Click here for a good source of information about fungi.

TRY GROWING YOUR OWN MOLDS IN A MOIST CHAMBER!!!

The material that supports the growth of a fungus is called its substrate. A commercially prepared medium like potato agar is one kind of substrate, but any organic material can be used.

The simplest method of growing molds is to put a substrate like bread in a moist chamber. The substrate provides nutrients, and the chamber maintains the high humidity that favors the growth of fungi. Placing a slice of bread, fruit or vegetable, or a leaf in a plastic sandwich bag is a simple way to use this method. The small plastic bag must have a tie, a fold-over top or another way of sealing it. Mold growth should be visible after 3 to 5 days. If you want to try this experiment, follow the directions below.

You will need the following items:

• Substrate material
• Sandwich bags with a tie, fold top or “zip lock”.
• A marker to label the bags.
• Damp, NOT WET, paper towels.

Making the moist chambers

• Label the bags with a number so you can tell them apart.
• Place a damp towel in each bag.
• Place a slice of bread or other substrate on top of the damp towel.
• Seal the bags.
• Record the substrate put in each bag.
• Place the bags in a warm area out of direct sunlight where they will not be disturbed.
• Check the bags each day. Fungal growth should be visible in 3 to 5 days. Fungi are fuzzy or hairy and may be green, white, black, yellow, etc. Bacterial colonies are shiny or slimy and may also be different colors.
• Record the number, color, and size of the fungal colonies. One very fast growing fungus, the Galloping Grey Ghost (Rhizopus stolonifer), may completely cover bread in just a couple of days.

Questions to help design experiments

• Does the amount of light affect the growth of mold?
• Does moisture affect the mold growth?
• Does temperature affect the mold growth?
• Are there differences in the numbers and kinds of fungi growing on different kinds of bread?
• Does preservative in some bread affect the numbers and kinds of molds?
• Are there differences in the numbers and kinds of fungi growing on bread compared to carrots?

TRY GROWING YOUR OWN YEAST !!!

The yeasts are one very important group of fungi. The common yeast used in baking bread grows very fast. You can complete an experiment in two days! The basic idea in this method is to measure the amount of carbon dioxide (CO2) released during the growth of yeast. The growth of the yeast stops when one of the nutrients required by the yeast is gone, or when the liquid gets too acid (low pH) and kills the yeast. If you want to try this experiment, follow the directions below.

• A teaspoon measure
• A permanent marker
• Active dry yeast (used in baking bread–do not use quick-rising varieties.) This yeast is available in jars if you are planning on doing a large experiment.
• Bottled soda pop or water in equal amounts. Different items contain different ounces per container. Shake each soda bottle and let the foam settle before opening, or open and allow to go flat overnight.
• Identical round, thin latex balloons–“water balloons” are slow to expand. Non-Mylar® “helium-quality” balloons give good results.

Directions for growing yeast

• Label each bottle with a number to keep track of what each one contains–control, treatment and contents, so that you can tell bottles containing the same solution (replicates) apart. Color is not a reliable means of identification–the caramel color used in cola is a carbohydrate and the yeast can eat it.
• Put a teaspoon of dried yeast in each bottle.
• Seal the bottles tightly and shake the bottle.
• Remove the lids and stretch a balloon over the mouth of each bottle. The balloon should fit very tightly so that the carbon dioxide does not leak into the air.
• Place each container in a warm area out of direct sunlight (top of refrigerator or clothes dryer) where they will not be disturbed.
• Record the diameters of the balloons, time since start of experiment, etc. for each bottle. One good method of measurement is to wrap a string around each bottle at its widest point, and then measure the length of the wrapped string against a yardstick. Record any other things you see happen. Did the color change? Did one balloon have a hole in it?
• Calculate the average diameter of the balloons in each treatment and the controls. The average is calculated by adding all the diameters of all the balloons in a treatment then dividing by the number of balloons in the treatment.
• Compare the results (average balloon diameters) of the experiment.
• A graph of the averages might help show your results.
• Is the average of the treatments larger than the average of the controls?
• Is the average of one treatment larger than the averages of the other treatments?
• Is carbonated water a better control than non-carbonated water in experiments with different kinds of soda pop?
• Is the amount of sugar used in a bottle related to the amount of carbon dioxide released into the balloon? Hint: graph sugar concentration versus average balloon size.

An Alternative to the Balloon Method for Measuring Yeast Respiration

The apparatus shown in the picture permits more accurate measurement of yeast respiration than the balloon approach. The carbon dioxide respired by the yeast is trapped in an upside down graduated cylinder. The milliliters marked on the graduated cylinder let you read directly the amount of carbon dioxide trapped.

You will need:

• graduated cylinder (100 ml shown).
• beaker or bowl.
• rubber or plastic tubing.
• one hole rubber stopper. A number 3 stopper fits most 1 liter plastic soda bottles.
• short glass or plastic tube. A medicine dropper or piece of a 1 ml plastic pipette might work. The tube should not touch the liquid culture in the flask or bottle.
• Erlenmeyer flask or soda bottle (500 ml flask shown).

Directions for assembly:

• Buy one-hole rubber stoppers that fit your bottles or flasks. Your teacher may be able to help or hobby stores that sell chemistry sets often have the supplies you will need.
• Insert a short piece of glass or plastic tubing in the hole in the stopper. It will be easier to insert the tube if you put salad oil on the outside of the tube. BE CAREFUL. If you break the glass tube you may cut yourself.
• Measure and cut a piece of rubber tubing long enough to reach from the flask to the lower part of the graduated cylinder.
• Slide one end of the rubber tubing over the tube in the rubber stopper.
• Fill the beaker or bowl with water.
• Fill the graduated cylinder all the way to the top with water.
• Cover the top of the graduated cylinder with your hand and quickly turn it over and put it in the beaker filled with water.
• Remove your hand. There should not be any air in the graduated cylinder. If there is a small amount of air, record the amount (ml). You will need to subtract this amount from the total in the cylinder when you take respiration measurements.
• Fill the flask or bottle with your liquid yeast culture.
• Insert stopper in the flask or bottle.
• Insert the end of the rubber tube in the graduated cylinder. Do not lift the end of the graduated cylinder out of the bowl or it will fill with air.

Question/ Purpose:

What do you want to find out? Write a statement that describes what you want to do. Use your observations and questions to write the statement.

Temperature, moisture and light are among the factors that may be studied for their effect on the growth of mold, yeast, or any other fungi.

These are samples of how you may define a question or purpose for your project.

The purpose of this project is to identify the effect of light on the growth of mold.

Note that instead of light you may choose other factor and modify your experiments accordingly. You can also substitute mold with yeast. This is another example:

The purpose of this project is to find out “How does the type of substrate affect the growth of yeast?”.

Substrate is a combination of food and growth media. Substrates such as water, sugar water, starch solution, flat soda,.. may be compared.

You may be much more specific and have a purpose like this:

Does yeast need air to grow?

Identify Variables:

When you think you know what variables may be involved, think about ways to change one at a time. If you change more than one at a time, you will not know what variable is causing your observation. Sometimes variables are linked and work together to cause something. At first, try to choose variables that you think act independently of each other.

This is a sample of how you define the variables:

• Independent variable (also known as manipulated variable) is light.
• Dependent variable (also known as responding variable) is the mold growth.
• Controlled variables are temperature, substrate type (type of bread), moisture.
• Constants are all other experiment conditions such as the source of bread, type and size of the plastic bag.

You may want to study other factors (Independent variables) as well. Just make sure that the independent variables must be tested ONE at a time.

Hypothesis:

Based on your gathered information, make an educated guess about what types of things affect the system you are working with. Identifying variables is necessary before you can make a hypothesis. This is a sample of hypothesis:

My hypothesis is that molds grow best in a dark environment. Possibly light or certain radiations in the light spectrum can slow down or prevent mold growth.

This hypothesis is based on my personal observation on where mold is usually found at home.

Experiment Design:

Design an experiment to test each hypothesis. Make a step-by-step list of what you will do to answer each question. This list is called an experimental procedure. For an experiment to give answers you can trust, it must have a “control.” A control is an additional experimental trial or run. It is a separate experiment, done exactly like the others. The only difference is that no experimental variables are changed. A control is a neutral “reference point” for comparison that allows you to see what changing a variable does by comparing it to not changing anything. Dependable controls are sometimes very hard to develop. They can be the hardest part of a project. Without a control you cannot be sure that changing the variable causes your observations. A series of experiments that includes a control is called a “controlled experiment.”

For example, in one experiment you may study the effect of light on growing mold. You may take three pieces of bread in three identical plastic bags and keep one of them at normal light to be your control and place two others, one in a dark place, and the other exposed to more than normal light. For a more reliable result you may use more samples. For example you may place 5 samples in a dark place, 5 samples in normal room light and 5 samples under a strong light source such as fluorescent light.

About Mold Experiment

As you know, we keep food in refrigerators so it will last longer. But still, sometimes you open a bag of bread or a jar of spaghetti sauce and what do you find? Mold!!

Ever wonder exactly what mold is? And how did it get there? And why sometimes it’s green and other times black or white? Did you know mold is a fungus and is alive and growing?

In this experiment, you’ll find out all about those colorful, fuzzy fungi by growing your own crop. Print out these pages and follow the directions to do this experiment at home. When you’re done, try answering the questions below.

Note: This is a long-term activity. It will take several days for the mold to grow. The first day should take you about 30 minutes to one hour to prepare everything. For safety reasons, don’t eat or drink while doing this experiment. And don’t taste or eat any of the materials used in this activity.

You’ll Need:

• 3 eye droppers
• small cup filled with 4 teaspoons or 20 mL of sugar water (see directions for preparing sugar water below)
• small cup filled with 4 teaspoons or 20 mL lemon juice
• small cup filled with 4 teaspoons or 20 mL tap water
• 4 slices of plain white bread*
• 4 slices of assorted bread, such as wheat, rye, sourdough, etc.*
• 8 resealable plastic sandwich bags
• masking tape

*It’s best if you use newly bought, fresh bread to make this experiment as accurate as possible.

Preparing sugar water

Note: Young people who don’t have experience operating a stove or microwave oven should get help and supervision from an adult. Parents or supervisors of young children may consider doing this step themselves.

Microwave: Stir 1/4 cup of sugar into 1/4 cup of water in a microwave-safe container and heat at one-minute intervals until sugar dissolves. Water will not need to reach boiling. Use potholders or oven mitts to handle container. Allow the mixture to cool for about five minutes before using.

Stovetop: Stir 1/4 cup of sugar into 1/4 cup of water in a small saucepan. Heat over medium heat until the sugar is dissolved. Use potholders to handle hot saucepan. Allow the mixture to cool for about five minutes before using.

What To Do:

1. Using masking tape and marker, make labels for four sandwich bags. Label the first bag “Dry White Bread.” Label the second “Water on White Bread,” the third “Lemon Juice on White Bread,” and the fourth “Sugar Water on White Bread.”

2. Wash your hands. Place a slice of white bread in the bag labeled “Dry White Bread” and seal the bag. Using one eye dropper, sprinkle 20 drops of tap water on another slice of white bread. (Don’t overdo it; the bread should be moist, not wet. If your bread is dripping, you’ve definitely done way too much. Throw away that slice and try again.) Place the moist bread in the bag marked “Water on White Bread” and seal the bag. Using a different eye dropper, sprinkle 20 drops of lemon juice on another slice of white bread and put it in the bag marked “Lemon Juice on White Bread” and seal the bag. Using your third eye dropper, sprinkle 20 drops of sugar water on the last slice of white bread and place it in the bag labeled “Sugar Water on White Bread” and seal. Try to keep your fingers off moist spots when handling each slice of bread.

3. Repeat steps 1 and 2, but this time use a different kind of bread in the remaining four bags. Your labels should note what kind of bread you’re using. Wash your hands when you’re done.

4. Make sure all of your bags are tightly sealed. Place all eight bags in a dark, warm place (about 86 degrees Fahrenheit, 30 degrees Celsius). Check with your parents or supervisor about where to store the bags. Check the bags each day for two weeks and record the results in a notebook. You may wish to draw or take pictures of the bread slices. Don’t open the bags!

5. Make a graph recording the total growth of mold on each of the four white bread slices at the end of two weeks (see sample graph on right). Make a similar graph for the other four bread slices. Compare the results. At the end of the two weeks, throw out all the bags unopened.

• From this activity can you tell what helps mold to grow best?
• Does it matter what kind of bread you use?
• What causes the different colors you see?
• What would happen if you left the bags in a well-lit place instead of a dark place?
• What would happen if you changed the temperature?

Answer 1: Unless you used bread that had been sitting out for many days, you probably didn’t get much or any mold growth on the dry bread. Clearly, water is important for the growth of mold. The mold grew best on bread sprinkled with sugar water because the sugar serves as food for the fungi. The more food that’s available, the more fungi cells can grow. The mold also grew pretty well on the bread with plain tap water because the fungi could use the sugar and starch in the bread as food. The mold didn’t grow as well on the bread sprinkled with lemon juice because lemon juice is acidic. Acids hinder the growth of many common fungi and bacteria. Answer 2: Molds grow better on some kinds of breads than others depending on the ingredients used and how the bread was made. Some breads are dry and some are moist. The amount of the sugar in different breads varies; some have sugar, honey or molasses added. Some breads are even acidic, such as sourdough. Some may have fruit or nuts or other ingredients added. Many commercial breads are made with preservatives that hinder the growth of molds and bacteria to prevent or delay spoilage. Bread baked fresh in a bakery that doesn’t use preservatives will more likely become moldy faster. All of these factors can influence how much mold will grow on a particular kind of bread.

Answer 3: Many of the colors you see on the moldy bread are due to the spores the fungi have produced. Molds reproduce by making spores at the end of stalks that rises above the surface of the bread, giving molds a fuzzy appearance. Spores are like seeds—they spread molds to new places so that they can continue to grow. Spores are usually colorful. Some fungi, such as Rhizopus nigricans (rye-zoh-puss neye-grih-cans) and Aspergillus niger (As-per-jill-us neye-jer), make black spores. Neurospora crassa (new-rah-spore-ah crah-sah) produces spores that appear pink. And the Penicillium (pen-ih-sill-ee-um) molds, the molds that make penicillin, are blue-green.

Some of the colors on your bread may be the result of growing colonies of bacteria, which also sometimes grow on old food. For example, a bacterium called Serratia marcescens (ser-ay-shuh mar-seh-sens) forms reddish colonies. You can tell bacteria colonies apart from molds because bacteria colonies appear smooth while molds look fuzzy.

Answer 4: Molds grow best in the dark, so not as much mold would be present on bread slices kept in a well-lit place.

Answer 5: Most fungi grow best around room temperature. But they can grow at a range of temperatures from cold (like in a refrigerator) to quite warm (body temperature). At temperatures colder or warmer than their favorite temperature, they usually do not grow as rapidly. If the temperature is too cold or too hot, they will not grow at all, and may even be killed.

Yeast growth experiment

As you probably know from eating numerous meals, all breads are not the same. Tortillas and pitas are flat and dense, while loaves of sandwich bread and dinner rolls are puffy and lighter. In fact, if you look closely at a piece of sandwich bread, you can see a honeycomb texture in it where bubbles formed and burst. Why these differences? Aren’t all breads made of the same basic ingredients? What made those bubbles?

The differences are caused by a microbe called yeast, pictured here. Yeast is a kind of fungus. If you open up a package of baker’s yeast bought from the supermarket and sprinkle some out, you’ll see tiny brownish grains.

These are clumps of dehydrated yeast cells (dehydrated means most of the water has been removed). Let them sit there for a while and watch them and you’ll soon get bored. They don’t exactly do much, do they? But put them in bread dough and after a while you can definitely see that they must be doing something. But what exactly are they doing?

You’ll find out in this activity in which you’ll make your own bread dough.

Note: This activity can be done within one hour, though you could stretch it over a few hours if you wish, depending on how many different sweeteners you want to try.

• 2 cups of flour (plus a little extra)
• 4 medium-sized bowls
• 2 packages of rapid-rise yeast
• access to warm water
• 6 teaspoons of sugar
• a sweetener besides sugar such as honey or artificial sweetener
• 24 clear drinking straws (must be clear)
• 24 clothespins
• measuring spoons
• ¼ cup measuring cup
• metric ruler
• permanent marking pen
• notebook and pen or pencil
• clock, watch or timer

1. Using the ruler, measure the point 3 centimeters from one end of each straw and mark that point with a line using the permanent marker.

2. Put ¼ cup of flour into each of your bowls. Mark the first bowl as the “Control.” Mark the others as 1, 2, and 3. (Just imagine that the dough in the illustration below is in four separate bowls.)

3. Measure 1 teaspoon of sugar and add it to the flour in the bowl marked 1. Put 2 teaspoons of sugar into bowl 2. Put 3 teaspoons of sugar into bowl 3.

4. Pour ¼ of a package of yeast (or ¼ teaspoon) into each of the four bowls. Using the spoon, stir together the ingredients in each bowl starting with the Control bowl.

5. Fill a cup with warm water from your faucet. The water should be warm, not hot and steaming. Dust your hands with a little flour. Carefully add the water to the Control bowl about a teaspoonful at a time and begin to knead the mixture. Your dough should eventually feel kind

of like Play-Doh—it should be damp, not wet. It’ll be sticky at first, but should eventually reach a point where it’s just damp enough that it no longer really sticks to the bowl or your hands. If it’s too sticky still, add a little bit more flour. Form the dough into a ball.

6. Repeat step 5 with each of the remaining bowls, working as quickly as you can. (If you have friends or classmates or parents helping out, each person should take a bowl and everyone should do step 5 at the same time.)

7. Working quickly, push three straws into the Control dough until the dough inside the straw reaches the 3-centimeter mark. Lay these straws by the Control bowl. Repeat this step with each of the remaining bowls.

Be sure to keep the straws beside the right bowls and don’t mix them up. (Again, if you’ve got more people working with you on this activity, each person should take a ball of dough and everyone should do this step all at the same time.)

8. Now pinch the bottoms of each of your Control dough straws, pushing the dough up from the bottom enough to clip a clothespin to the end of each straw. Mark the new height of the dough on each straw. Stand the straws upright using the clothespins as bases. Do the same with the rest of the straws. Label the batches of straws as Control, 1, 2 and 3.

9. Mark the time on your clock or watch or set your timer for 10 minutes. Wait 10 minutes. Then measure and mark the heights of the dough in each straw and record these heights and the time in your notebook. Repeat this step 10 minutes later. Repeat after another 10 minutes has passed.

10. During the 10-minute intervals while waiting for the dough in the straws to do its thing, discard your first batches of dough from each bowl and wash the bowls out. Dry them thoroughly. Be sure to keep an eye on the clock while you’re doing this so that you don’t miss the 10-minute deadline to check and measure your straws.

11. Repeat the dough making process only this time use a different kind of sweetener than sugar. Repeat the steps of filling and marking the straws. Label the new batch of straws and set them away from your first batch. Repeat the process of measuring the dough height in the straws at 10-minute intervals and recording the results in your notebook. Be sure to record the heights of this new batch of straws separately from the first batch.

12. Graph your results. First, calculate the average final height for each set of three straws in your first batch. Make a bar graph showing these average heights with the number of teaspoons of sugar (0, 1, 2, 3) on the horizontal axis and the height in centimeters on the vertical axis. Make a similar bar graph for your second batch of straws. See the sample graph on the right.

13. Throw away all the straws when you’re done. You might want to save the clothespins for another project in the future. Discard the dough in the bowls and wash them out. Clean up any spilled flour, sugar or yeast.

• In the first batch of straws you made, which straws showed the greatest change in dough height? Why?
• Can you guess what effect the sugar had and why?
• Did the Control dough rise at all or not? Why or why not?
• Did your dough made using a different sweetener besides sugar show the same results?

Answer 1: The straws containing dough from bowl 3 showed the highest rising. Since everything—the amount of flour, the amount of yeast, the temperature of the water—stayed the same except for the amount of sugar, you have probably already rightly guessed that the height of the dough rising is connected to the larger amount of sugar in this dough. Why is that? See the next question.

Answer 2: You will notice that the dough from the other bowls also rose some in their straws, the height connected to how much sugar was in the flour. The more sugar, the higher the dough rose. What can you figure out from this? Well, you’ve already read that yeast makes bread rise and become puffy instead of flat and this has something to do with yeast activity. What makes living things active? Food energy. The sugar is food for the yeast cells. The more sugar there is, the more active the yeast cells are.

Yeast cells chow down on the sugar molecules, breaking them apart in a chemical reaction and turning them into simpler elements and compounds including carbon dioxide. Carbon dioxide is a gas. Bubbles of carbon dioxide released by the yeast get trapped in the dough as bubbles. As more and more of these bubbles build up, the dough puffs up or rises. When the dough is put in the oven and baked, the carbon dioxide vaporizes in the heat, leaving spaces where the bubbles once and giving bread its honeycomb texture.

Answer 3: You probably saw some rising happen in the straws containing Control dough. This is because flour is a starch. Starches contain glucose, a form of sugar (this is why a saltine cracker tastes a little sweet if you let it sit on your tongue for a while; the enzymes in your saliva break the cracker starch down into glucose and other simpler molecules). So even though you didn’t add any sugar to the Control dough, it already contained some for the yeast to much on. However, because the amount of sugar in this dough was much less than in the others, less carbon dioxide could be made by the yeast in this batch and the dough couldn’t rise as much in comparison.

Answer 4: Different sweeteners will have similar or lesser effects on dough rising as sugar. You could try this experiment with as many different types of sweetening agents as you want to compare the results. Then you could do some research on the types of sugars in these different sweeteners to determine which ones work best as food for yeast.

Stop the Mold: A Bread Mold Study

This experiment examined how alcohol , pickle juice and mercurochrome affect mold growth. Mercurochrome and ethanol were selected because each stops wounds from infection. Pickle juice, a weak acid, was chosen to examine whether decreasing pH would inhibit mold growth. Method: Mold was grown on bread allowing enough growth so that mold type could determined. The most common mold growing was used to inoculate other four slices of bread. Three drops of mercurochrome, pickle juice, alcohol were each added to a slice, leaving the fourth slice as a control. Mold growth was recorded daily. Results: Pink, green, yellow and black molds grew on the bread. The green mold was used for this study. None of the agents tested totally inhibited mold growth although pickle juice worked the better than the other agents.

The main types of mold inhibitors are (1) individual or combinations of organic acids (for example, propionic, sorbic, benzoic, and acetic acids), (2) salts of organic acids (for example, calcium propionate and potassium sorbate), and (3) copper sulfate. Solid or liquid forms work equally well if the inhibitor is evenly dispersed through the feed. Generally, the acid form of a mold inhibitor is more active than its corresponding salt.

Any other chemical substance may also be tested for its effect on mold.

INTRODUCTION

To experiment with fungi, mycologists often need to grow them. Simply allowing bread to become moldy is not an experiment. An experiment is the test of an idea. Often, this idea is expressed in the form of the question: what? What if…? What happens when…? What kind of effect…? Experiments are designed to use the methods and materials that will give the most complete and accurate answer to an inquiry.

DESIGNING EXPERIMENTS

Fungi break down and absorb organic material for their nourishment, so any experiment must first provide them with food. Oxygen and moisture are also necessary. A material for the growth of fungi for experiments is called a medium.

Most commercially prepared media for growing fungi are extracts of plant materials like potatoes. A medium that is specially prepared to contain only the exact nutrients required by one species of fungus is called a “minimal medium”.

The choice of growth medium depends on the question that is being asked. If the question is “What kinds of fungi grow naturally on bread?” the choice of medium is simple. You could just put a slice of bread in a plastic bag, close it to retain moisture and await mold growth.

However, observing only one slice of bread would not make an effective experiment. Your chosen slice may not have any mold spores on it, or contain spores of all the species present in the loaf. It might be too dry to allow growth. You would have to use a number of bags to account for all reasonably possible growth failures and successes. The slices of bread would be replicates. Replicates allow the treatment to be repeated often enough to allow you to determine if the results are significant or the product of random chance..

You will also need to decide how to record your results. Do you identify each species of mold by its scientific name, or do you just describe them (fluffy red colonies, white fuzzy spots, blue-green velvet, etc.?)

A more complicated question requires the design of a more complicated experiment. At first glance, “What effect does the preservative in some breads have on mold growth?” seems as if it could be answered with a loaf of bread and some plastic bags, like the first experiment. However, the best experiment on the effect of a preservative on mold growth would use two loaves of bread. These loaves would be identical in preparation and ingredients, except for the presence or absence of the preservative. The bread without the preservative would be the control and the bread containing the preservative would be the treatment. Replication of both treatment and control gives the experimenter a way to understand the effect of substance by showing what happens when it is both present and absent.

Materials and Equipment:

Can be extracted from experiment design.

Results of Experiment (Observation):

Experiments are often done in series. A series of experiments can be done by changing one variable a different amount each time. A series of experiments is made up of separate experimental “runs.” During each run you make a measurement of how much the variable affected the system under study. For each run, a different amount of change in the variable is used. This produces a different amount of response in the system. You measure this response, or record data, in a table for this purpose. This is considered “raw data” since it has not been processed or interpreted yet. When raw data gets processed mathematically, for example, it becomes results.

Calculations:

No calculation is required for this project.

Summary of Results:

Summarize what happened. This can be in the form of a table of processed numerical data, or graphs. It could also be a written statement of what occurred during experiments.

It is from calculations using recorded data that tables and graphs are made. Studying tables and graphs, we can see trends that tell us how different variables cause our observations. Based on these trends, we can draw conclusions about the system under study. These conclusions help us confirm or deny our original hypothesis. Often, mathematical equations can be made from graphs. These equations allow us to predict how a change will affect the system without the need to do additional experiments. Advanced levels of experimental science rely heavily on graphical and mathematical analysis of data. At this level, science becomes even more interesting and powerful.

Conclusion:

Using the trends in your experimental data and your experimental observations, try to answer your original questions. Is your hypothesis correct? Now is the time to pull together what happened, and assess the experiments you did.

Related Questions & Answers:

What you have learned may allow you to answer other questions. Many questions are related. Several new questions may have occurred to you while doing experiments. You may now be able to understand or verify things that you discovered when gathering information for the project. Questions lead to more questions, which lead to additional hypothesis that need to be tested.

Possible Errors:

If you did not observe anything different than what happened with your control, the variable you changed may not affect the system you are investigating. If you did not observe a consistent, reproducible trend in your series of experimental runs there may be experimental errors affecting your results. The first thing to check is how you are making your measurements. Is the measurement method questionable or unreliable? Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically.

If you determine that experimental errors are influencing your results, carefully rethink the design of your experiments. Review each step of the procedure to find sources of potential errors. If possible, have a scientist review the procedure with you. Sometimes the designer of an experiment can miss the obvious.

References:

Visit your local library and find some books and publications related to mold or fungus. Following are some online resources.

About Mold: http://www.e-tulsa.net/mold1.htm l

• Mildew Diseases
• Fungi of California
• Fungi of Sierra Nevada
• Tayside fungi

It is always important for students, parents and teachers to know a good source for science related equipment and supplies they need for their science activities. Please note that many online stores for science supplies are managed by MiniScience.

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Which Cheese Molds The Fastest Science Project

Table of Contents:

Cheese Mold Experiments . Comparing Molds – Creating and observing moldy cheese is a popular science fair experiment. These types of experiments can help to discover what cheeses are most resistant to mold and why, a fact that is useful in numerous real-life situations. Campers and backpackers are among a few people who find this information invaluable. The rate of mold growth can be tracked and explained as the spores grow. Always exercise caution when growing mold, as some types are toxic. Types of Cheese Try purchasing several types of cheeses with different textures. For example, compare the hardness of Parmesan with a semisoft cheese like cheddar and a soft cheese like mozzarella. Keep the cheeses out of the refrigerator to promote the mold growth. Place them in a container where they can breathe, such as a bowl covered with a loose lid or plastic wrap, and set it out of the sunlight. Every day or so, check the cheese for mold growth. You can even use a ruler to measure the height of the mold as it grows. Mold Resistance There are a number of ways to influence the speed of mold growth.

Mold Bread Experiment

We are going to perform a mold bread experiment to grow our own mold and find out whether mold does indeed grow faster at higher temperatures.

• Important Note
• What You Need for the Mold Bread Experiment

Video advice: Moldy Cheese

Roger Sherman 2nd grade science fair project. Which Cheese Grows Mold the Fastest

Further Experiments

In ten days you will be able to answer this important question and make a contribution to science! But what is mold? What makes it grow? What is Mold? Mold is something that we often take for granted, as something that makes us have to throw the bread away or the cheese smell bad. Mold is, in fact, a fascinating organism which has had many different uses over the years and our lives would not be the same without it. Most of us know that food seems to become moldy more quickly in the summer than in the winter when it is colder. Food in refrigerators seems to keep longer than food left out in the sun. Is this true? Does temperature really affect the rate at which mold grows? Important NotePlease note that some people are allergic to mold; ask your doctor or parents. If this is the case, do not pick the Mold Bread Experiment. Always wear gloves and a mask, wash your hands, and don’t eat or drink whilst you are performing this study. Performing the Mold Bread ExperimentHypothesisIn the Mold Bread Experiment we are trying to prove that;”Mold grows quicker at higher temperatures.

What type of cheese grows mold the fastest?

If I keep the cheeses out of the fridge uncovered then, the Cheddar will mold faster than the American cheese because, the Cheddar is less processed than the American Cheese and, having less preservatives will cause the Cheddar to mold at a faster rate than the American.

I believed that the Cheddar would mold the fastest and during both trials it was the Cheddar that molded the fastest. I believe the Cheddar molded the fastest because it is less processed than the sliced American cheese. semi-soft cheeses, like Mozzarella, Monterey Jack and Feta, for about 2 to 3 weeks. firm cheeses, like Cheddar, Colby and Swiss, for 5 weeks or more. hard cheeses, such as Parmesan, for up to 10 months. why does some cheese mold faster than others? Moisture content is important, as well as pH levels. Higher-moisture cheeses tend to grow mold faster, but cheeses with a high pH level will fight off mold better. In the cheese-comparison test, the softer, higher-moisture cheeses should grow mold faster. Furthermore, how do you speed up mold on cheese? Keep the cheeses out of the refrigerator to promote the mold growth. Place them in a container where they can breathe, such as a bowl covered with a loose lid or plastic wrap, and set it out of the sunlight. Every day or so, check the cheese for mold growth.

Which Cheese Grows Mold the fastest?

Which Cheese Grows Mold The Fastest Biology Projects, Biology Science Fair Project Ideas, Biology Topics for CBSE School,ICSE Biology Experiments for Kids and also for Middle school, Elementary School for class 5th Grade,6th,7th,8th,9th 10th,11th, 12th Grade and High School, MSC and College Students.

15. Prepare your report and include all of the following: a clear statement of the problem, your hypothesis, the rationale for your hypothesis, and a list the materials used. Include the safety precautions taken. Describe the procedures used. Include all the data that were gathered. Include all charts and graphs.

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On the information level, this experiment serves to introduce students to the conditions under which molds grow, how they can be useful to us and how their growth can be controlled. In addition, the students learn how to conduct the experiment in a safe manner to prevent the effects of contamination. On the level of experimentation, this experience serves to acquaint students with the essential components of sciencing such as the importance of clearly defining the problem to be investigated, stating their hypothesis and their rationale for the hypothesis, the use of a control, of identifying dependent and independent variables, of data collection, of pictorial and or graphic presentation of data and of being able to make better judgments as to the validity and reliability of their findings. They take on the role of scientists and in the process they learn to act as one.

Which bread molds the fastest science experiment?

Wet bread molds more quickly than dry bread because mold thrives in damp environments. If you did an experiment and tested one slice of dry bread and one dampened slice of the same bread, the dampened slice would grow mold much more quickly than the dry one.

Observe the mold growth. It should take around 7-10 days before you will be able to see significant growth on the bread. You could see growth as soon as 5 days depending on the type of bread you used. Remember, fresh bread will mold faster than store-bought bread containing preservatives.

Which bread molds the fastest science experiment? What’s the fastest way to grow mold on bread? Which food will mold the fastest experiment? Which food will mold the fastest science fair project hypothesis? Do different types of bread grow mold faster? Which bread molds faster wheat or white? Does bread mold faster in the dark? Does dairy mold faster if not refrigerated? How long does it take for bread to mold? Which fast food burger molds the fastest Science Project 2017? How fast does bread mold science project?

Video advice: Mold… It’s in the cheese

Emme’s science fair

Which cheese molds the fastest science fair project?

One of the times they did the experiment, the cheddar molded fastest.

Milk is the fastest when it comes to molding because it has these building compounds that triggers fast decomposition. However, your conclusion be based on the actual results of this 8th grade science fair project. 8th grade science fair projects, banana, bread, cheese, fruits, milk, molds, science project.

Which cheese molds the fastest science fair project? What kind of bread molds fastest? Does cheese mold quickly? Does mold grow faster on cheese or bread? Does mold grow faster in warm or cold? Why is my cheese molding so fast? How to make your food mold the fastest? Which is type of bread molds the fastest? What foods have the least number of molds? Which is food molds the fastest to decomposition? Which bread will mold faster? What foods are moldy? Which bread molds faster research? Is moldy food dangerous?

Science Fair Project Idea: Why Do Some Foods Mold Faster Than Others? – Looking for a simple and engaging idea for your science fair? You’ll love this detailed look at why some foods mold faster than others.

This was my son’s first time presenting a project in front of his peers, and he did a fantastic job of maintaining his composure and feeling confident in his quality of work. Such a great way to end his time in elementary school, and prepare for the projects and presentations that will be a part of middle school next year.

How does mold grow on food science project?

With the growing popularity of “food science” projects, we decided to analyze the growth of mold on food. We decided that the best way to do this was to test the growth of one of the most common “food science” projects: growing artichoke hearts in a test tube. The goal of our test was to (…)

Food spoilage is caused by microscopic microorganisms. These microscopic creatures, known as spoilage bacteria, eat unprotected goods and create waste. Bacteria will grow as long as food and water are available, which may be very quickly. Bacterial waste is the source of ruined food’s unpleasant odor and rotting look.

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• How does food mold grow?
• Which food will mold the fastest science project?
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What causes food to spoil?

Mold can be a problem that you have to deal with when you are trying to grow your food science project. Mold is a problem that you have to deal with when you are trying to grow your food science project. Mold is a problem that you have to deal with when you are trying to grow your food science project. Mold is a problem that you have to deal with when you are trying to grow your food science project. Mold is a problem that you have to deal with when you are trying to grow your food science project. Mold is a problem that you have to deal with when you are trying to grow your food science project. Mold is a problem that you have to deal with when you are trying to grow your food science project.

Which food will mold the fastest science fair project? – Molds, the microscopic organisms that form on water- and nutrient-rich surfaces and produce their own food via photosynthesis, are found all around us. They live off of substances such as sugar, starch or decomposing plant matter in soil.

To develop mold on bread, gather the following items: a piece of any type of bread, a sealable plastic bag, a spray bottle, and water. Any kind of bread will do, but keep in mind that store-bought sandwich bread includes preservatives and will take longer to mold. Mold will develop quicker on fresh bread.

• What food will mold the fastest?

Which food will mold the fastest science fair project hypothesis?

• Which fruit rots the fastest science project?

My Cheese Experiment By: Kristin Ewing. Big question My big question is will American or Swiss cheese will mold faster? I want to know this because of. – Hypothesis My hypothesis is that the American cheese will mold faster than the Swiss cheese. I think this because the American cheese has more moister than the American does. American also has no holes in it like Swiss cheese does.

Step by step instructions Step 1. Put both American and Swiss cheese into two separate sandwich bags. Step 2. Place both bags on a smooth surface where it won’t be disturbed or harmed. Step 3. report any observations you see over the next week to see if American/Swiss cheese have molded. Step 4. Lastly in your notebook put down which cheese has molded the most in one week.

Athienah,I want to make sure we are on the same page. Sorry if the following information is obvious to you, I just want to make sure I understand what you are thinking. Most of the time in science, “runs” or “trials” means the same experiment is repeated multiple times. So 3 runs or 3 trials just means the same experiment was repeated 3 times, with the same control variables and independent variable being tested. So when I say to do at least 3 “runs” or “trials” I just mean that you should repeat the experiment 3 times to ensure that you have more accurate results and more data to analyze. The more trials you do the better your results will be. At least 3 trials is generally a good rule, but it depends on the experiment. (Experiments that involve giving a survey to people normally involve way more than 3 of them, for example). Right now we have talked about 3 independent variables: (1) the softness of cheese, (2) the degree of covering (uncovered vs. covered), and (3) preservatives (presence or lack of).

Science Experiment: Which Food Will Mold The Fastest? – It’s that time of year where science fairs are just around the corner, so to get you thinking about what you might do this year, here’s a fun experiment about mold growth on food! Let’s see what kind of food will mold first if left un-refrigerated. This experiment is brought to you by.

If you enjoyed this experiment, you might also enjoy LaMotte’s Microbe Hunter kits. With these kits, you can take a closer look at why bread, cheese and fruit grow mold, how producers set an expiration date, and perform more experiments on food samples using Tryptic Soy/Rose Bengal dipslides.

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Which food will mold the fastest science fair project?

Mold and yeast containing foods: Cheeses: all cheese, especially moldy cheeses like stilton are the worst, buttermilk, sour cream and sour milk products. Alcoholic drinks: beer, wine, cider, whiskey, brandy, gin and rum. Condiments: vinegar and foods containing vinegar, mayonnaise, pickles, soy sauce, mustard, relishes.

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The hypothesis he came up with is: The strawberries will mold the fastest, because they don’t have as many preservatives as the bread and cheese. Materials and Equipment Banana. Cheese. Milk. Bread. A cabinet in which to place the samples for one week. Paper and pencil. Camera. Also, why does milk mold the fastest? Milk provides an environment that is particularly favorable for the growth of microorganisms, resulting in the rapid growth of mold, yeast and bacteria. Milk is also cooled quickly to prevent natural souring, ensuring the milk keeps longer. In respect to this, how do you make something mold fast? To grow mold on bread you will need to collect the following materials: a slice of bread (any kind), a sealable plastic bag, a spray bottle, and water. You can use any type of bread, but know that store-bought sandwich bread contains preservatives and will take longer to grow mold. Fresh bread will grow mold faster. Why do some foods mold faster than others? The processed foods have preservatives that make it harder to grow mold on them, unlike the natural foods that have no preservatives, and mold a lot faster.

Video advice: A brie(f) history of cheese – Paul Kindstedt

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strawberriesThe hypothesis he came up with is: The strawberries will mold the fastest, because they don't have as many preservatives as the bread and cheese.

What makes cheese mold faster?

Higher-moisture cheeses tend to grow mold faster, but cheeses with a high pH level will fight off mold better. In the cheese-comparison test, the softer, higher-moisture cheeses should grow mold faster. In a test like the vinegar comparison, the high pH level of the vinegar should help to fight off mold growth.

What type of food allow mold to grow the fastest experiment?

The processed foods have preservatives that make it harder to grow mold on them, unlike the natural foods that have no preservatives, and mold a lot faster.

Does cheese mold quickly?

Because fresh cheeses are high in moisture, mold can spread quickly and make the cheese unsafe to eat. For aged or hard cheeses like parmesan, or cheddar, light surface mold can be dealt with by cutting around the moldy bit and removing it.

Which bread will mold the fastest science project?

Moisture Level of Bread Wet bread molds more quickly than dry bread because mold thrives in damp environments. If you did an experiment and tested one slice of dry bread and one dampened slice of the same bread, the dampened slice would grow mold much more quickly than the dry one.

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How mold appears on cheese.

Dear Heloise: A reader recently suggested that mold on cheese comes from bacteria because of human contact. Mold is a fungus that is not related to bacteria. It is a natural process in the aging/breaking down of organic matter. — Paula, in Vermont

HARD WATER STAINS

Dear Heloise: In a recent column, Pat L. asked how to clean rust on a toilet bowl, and I recently learned a quick, nonchemical, and effective way to clean my hard-water stains: pumice stone on a stick! It is safe for porcelain and cleared away a gray, mineral deposit ring that I couldn’t erase with anything else. All thanks go to a YouTube video! — Linda N., East Palestine, Ohio

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Dear Heloise: Do you have too many cardboard boxes that won’t fit or fill up the trash can? Spray the boxes with water! The cardboard becomes soft, pliable, and easy to bend. If you’re recycling these, allow the “bent” boxes to dry before placing them in the recycling container.

Cardboard can also be used as mulch when cut into small pieces. It break downs while protecting flowers and bushes or killing weeds. — Kay K., via email

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So, readers, what would you put on a peanut butter sandwich that is different and maybe even a little wild or crazy? — Heloise

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Leon, from the photograph you sent, it looks like weathering and frequent use are what caused the lighter areas on your chair. You can spray-paint your chair, but be sure to use a primer first, specifically one made for plastic outdoor furniture. — Heloise

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Mold Bread Experiment

What makes mold grow.

We are going to perform a mold bread experiment to grow our own mold and find out whether mold does indeed grow faster at higher temperatures.

This article is a part of the guide:

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• 1 Kids' Science Projects
• 2 How to Conduct Science Experiments
• 3.1 Mold Bread
• 3.2 Popcorn
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• 3.4 Corrosiveness of Soda
• 3.5 Egg in a Bottle
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In ten days you will be able to answer this important question and make a contribution to science!

But what is mold? What makes it grow?

What is Mold?

Mold is something that we often take for granted, as something that makes us have to throw the bread away or the cheese smell bad.

Mold is, in fact, a fascinating organism which has had many different uses over the years and our lives would not be the same without it.

Most of us know that food seems to become moldy more quickly in the summer than in the winter when it is colder. Food in refrigerators seems to keep longer than food left out in the sun. Is this true? Does temperature really affect the rate at which mold grows?

Important Note

Please note that some people are allergic to mold; ask your doctor or parents. If this is the case, do not pick the Mold Bread Experiment. Always wear gloves and a mask, wash your hands, and don’t eat or drink whilst you are performing this study.

Performing the Mold Bread Experiment

In the Mold Bread Experiment we are trying to prove that;

"Mold grows quicker at higher temperatures."( Hypothesis )

What You Need for the Mold Bread Experiment

• 15 slices of bread. Any sort will do but it is perfectly fine to use cheap white sliced bread as then you will know that all of the slices are a similar size, weight and thickness. You must make a note of the brand and use-by date so that anybody else wanting to repeat the Mold Bread Experiment can use the same type.
• 15 sealable sandwich bags
• 1 piece of film or clear plastic with a 10x10cm grid drawn onto it
• Clean knife
• Chopping board
• Sticky labels
• Mold Spores - if you can’t get these from your school don’t worry. There are mold spores all around us in the air which will eventually grow on the bread but your experiment will take longer.
• Using the sticky labels and the marker pen label the bags. Mark 5 bags as ‘A’, 5 as ‘B’ and 5 as ‘C’. You also need to label each set of bags 1 to 5.
• Cut the bread into 10 x 10 squares using the chopping board and knife.
• Inoculate the bread thoroughly with the mold solution. Try to coat each slice with a similar amount of the culture although this can be difficult.
• Put one slice of this bread into each bag and seal the bags tightly.
• Put the 5 ‘A’ bags into the freezer, the 5 ‘B’ bags into the refrigerator and the 5 ‘C’ bags somewhere safe in a warm room. Because the bags in the freezer and fridge will not be getting much light it is best to cover the ‘C’ bags to make sure that light is a constant.
• Every 24 hours, preferably at exactly the same time every day, using the plastic grid, count the number of square centimeters of mold on each slice of bread. If the mold covers more than half a square, count it as 1cm, if less than half a square, count as 0 cm. You must never open the bags.
• You should repeat these counting processes for 10 days or until there are significant measurable results .
• Keep a careful note of your results for each slice of bread for the entire duration of the experiment. You can even take pictures or draw the slices if you want to be really scientific!
• Average the results for sample types A, B and C.
• Once you have finished, throw out all of the bags without opening them.

Because each square of bread is 100 cm2, you can express your results as a percentage. For each of the bread types, A, B or C average the amount of mold grown over the ten days and write these figures into a table.

You can then plot this information onto a graph and begin to explore your results. You can plot the amount of mold on each bread sample and compare it to the number of days, like in the diagram below. This can be done with a sheet of graph paper and colored pens or on a computer.

Is the Graph Correct?

Could you replicate the graph below or is your graph different? We have done this, but will not give you our answer, so you can test for yourself!

Why are the Results Important?

The food industry spends millions of dollars every year on refrigeration and it is very important that they know what temperature they need to stop mold from growing. Moldy food must be thrown away and this costs restaurants and manufacturers a lot of money.

For companies using mold to make food or medicine they need to know at which temperature mold grows best. The faster the mold grows, the quicker they can sell their product and make money.

Further Experiments

Now that you have finished and obtained some results, maybe you want to see if other variables affect the rate at which mold grows. Maybe you could keep the temperature the same for all of the samples but use different types of bread.

You could try adding moisture to the slices or putting different amounts of sugar or lemon juice onto the slices. As long as you only vary one thing at a time, you can make some interesting studies about mold.

Temperature is not the only thing that affects the rate of mold growth so feel free to try and find out more about this interesting organism.

Facts About Mold

• Mold is not a plant but a fungus like mushrooms and toadstools. It grows on food and other organic matter, breaking it down into slime and extracting nutrients for growth.
• Alexander Fleming discovered that a common type of mold fungi kills germs. From this, he made a medicine called penicillin which has saved millions of lives over the last 80 years. Many other life-saving drugs are made from chemicals obtained from mold.
• Mold is one of nature’s cleaners. It breaks down dead organic material and recycles the nutrients back into the soil. It is essential in nearly every ecosystem in the world.
• We use molds for flavor in some foods such as blue cheese, soy sauce and Quorn (TM) .
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Martyn Shuttleworth (Nov 24, 2008). Mold Bread Experiment. Retrieved Aug 28, 2024 from Explorable.com: https://explorable.com/mold-bread-experiment

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