Is Bread Mold Dangerous

Is Bread Mold Dangerous. When you see mold on bread, the common household question is “What to do with it?” You want to be safe, but you don’t want to waste things.

You might be concerned about whether moldy patches on bread are safe to eat, whether they may simply be scraped off, or if the remainder of the loaf is safe to eat.

What mold is, why it grows on bread, and whether or not it’s safe to eat moldy bread are all discussed in this article.


Mold may take numerous shapes, from the hazardous black mold that grows in your house’s damp corners to minute fuzzy patches of periwinkle blue that bloom on slices of bread.

Yet, according to Betty Feng, an associate professor of food science at Purdue University, mold is a biological kingdom similar to mushrooms.

Molds are tiny fungus that may be found in practically every environment, Feng says to Inverse. Both indoors and out, it may be detected all year.

According to Feng, the mold has properties similar to a dandelion in terms of physicality. This indicates roots that are nearly undetectable, a towering stalk that rises above the surface, and spores floating through the air with their DNA.

What Is Bread Mold?

Mold and mushrooms are both fungus species. Fungi, such as bread, survive by breaking down and absorbing the materials’ nutrients.

Mold colonies of spores are what the fungus reproduces, and they are the fuzzy parts of mold you see on bread. Spores may grow on other areas of the loaf when they fly through the air inside (1).

Mold’s color is determined by the fungus’s type, which ranges from white through yellow to green through gray.

The color of the spots might alter as a result of changing growing circumstances and may vary throughout the fungus’s lifecycle (2Trusted Source), therefore you cannot identify the type of mold just by color.

Aspergillus, Penicillium, Fusarium, Mucor, and Rhizopus are some of the mold species that grow on bread. Each of these fungus species (3Trusted Source) comes in a variety of varieties.


Mold, like all living things, needs oxygen and nutrients to survive. That’s one of the reasons they are drawn to food, just like us.

According to Feng, “warm and humid conditions” are often favorable for mold growth. Mold spores “floating in the air” discover suitable circumstances for growth, which includes “very good food with a lot of nutrients.”

Jeffrey Farber, who has a Ph.D. in food science, is an adjunct professor at the University of Guelph. In the field of microbiology, food is called He explains that findings from Inverse indicate that little mold spores may find food elements like salt, sugar, and protein to be attractive settling blocks.

Nonetheless, according to Faber, further investigation is required to determine whether or not the molds are connected to these pleasant chemicals.

How Does Mold Grow on Bread?

Mold can grow on a wide range of materials, including food. Mold, for example, may develop on bread. It might be black, green, blue, yellow, or any other hue. It’s also possible that it has a fuzzy appearance.

Mold spores are often present in the air since it is a form of fungus. Mold spores find a welcoming environment in bread.

Mold spores are tiny plants that spread across the earth and encircle us at all times of day, filling every corner. Mycotoxins, which are harmful poisons that may cause serious illness, are formed by certain molds.

Breaking down sick yard waste and producing building blocks for antibiotics, miracle medications that have saved millions of people, are other molds that are beneficial.

Molds assist researchers understand the implications of humanity’s “biological clock” and how it functions. They also assist scientists decipher the genetic code. The fuzzy green and gray growth that affects the foods we keep, particularly breads, is one of the most common forms of this filamentous fungus.

What types of molds are dangerous?

Heavy mold proliferation may generate mycotoxins, which may change the chemical composition of gut flora, according to Healthline. Myotoxins have been connected to an elevated cancer risk in some cases.

Green mold also refers to molds like Cladosporium, Aspergillus, and Penicillium, according to Puro Clean. Despite Penicilium’s antibiotic qualities, it’s not a good idea to swallow it all at once.

Ultimately, green mold is seen to be more of a bother than a genuine safety concern. However, black mold is very different from the other. People often get worries when they hear the phrase “black mold.”

Humans and animals can be affected by black mold, a harmful fungus. Black mold, according to HGTV, causes respiratory problems, coughing, eye irritation, mental fog, chronic tiredness, and persistent headpains. However, it’s mostly seen in rooms rather than food.

Don’t Eat the Mold on Bread

Certain molds, such as those utilized to make blue cheese, are safe to eat. Bread, on the other hand, has an off-flavor and may be harmful to your health if it is infected with fungus.

Since it’s impossible to tell what sort of mold is developing on your bread by simply seeing it, it’s preferable to assume that it’s harmful and not eat it (1).

Also, since you might inhale fungal spores if you smell moldy bread, avoid it. Mold allergy may cause breathing difficulties, such as asthma, if you inhale it (1).

If eating mold in food, people with allergies to inhaled mold may suffer severe symptoms, including life-threatening anaphylaxis. (4Trusted Source, 5Trusted Source, 6Trusted Source) Nonetheless, this seems to be unusual.

Lastly, individuals with weak immune systems, such as those who have poorly controlled diabetes, are susceptible to Rhizopus infection via breathing it in. This illness is not very common, but it may be deadly (7Trusted Source, 8Trusted Source).


Penicillium Bread Mold

On bread and other foods across the globe, Penicillium is a genus of bread molds that can be found. Without thorough investigation, it is nearly impossible to distinguish between most Penicillium bread mold species.

Bread molds from Penicillium are one-of-a-kind. People utilize certain Penicillium molds to flavor foods, such as blue cheese, on purpose. Penicillium molds produce a substance called penicillin, which is utilized as an antibiotic by people.

Fuzzy white, gray, or light blue patches on bread are common signs of Penicillium molds. If a person has allergies, Penicillium is similar to black bread mold in that it is not normally harmful.

Certain Penicillium species, on the other hand, may generate mycotoxins, which have been linked to cancer and other diseases. As a result, prolonged contact with penicillium molds may harm a person’s health.

What Are The Different Types Of Bread Mold?

Rhizopus stolonifer (black bread mold)

Black bread mold’ is a common name for Rhizopus stolonifer, which grows on bread and is quite prevalent. This mold on bread looks fuzzy, and it has a tendency to appear light in color (typically blue, green, or white) when it first emerges.

The mold spot becomes black in color as spores are produced at the ends of aerial hyphae throughout time. R. is a abbreviation for “radioisotope.” Stolonifer forms circular patches that spread quickly over bread’s surface.

Penicillium sp

Spore-forming Penicillium species The most prevalent kinds of mold on breads are these. It appears as white, gray, or blue hazy patches that are lightly colored. Penicillium is a type of fungus. They may be found on bread kept in the fridge if they grow at colder temperatures.

Mycotoxins can be produced by the Pencillium molds if they are not carefully controlled, and may be harmful if consumed in high quantities on a regular basis.

Cladosporium sp

Cladosporium sp. is a fungus that can be found growing on trees. Large and spherical mold patches that seem to be smooth may be noticed on bread. They range in hue from dark green to black and are commonly tinged with a reddish tint.

Cladosporium mold also poses a higher risk of causing allergic reactions in individuals who are sensitive to mold.

Aspergillus sp

Spore-forming aspergillus fungus Since numerous distinct Aspergillus species may develop on bread, the color of mold spots may vary greatly. They appear as fuzzy areas on bread. The color of Aspergillus mold spots on bread is usually yellow or light green.

Mycotoxins are produced by certain strains of Aspergillus mold that grow on bread, and they should not be eaten.


So what if you didn’t realize your apple or bread was rotting before taking a big bite? What’s the worst that can happen if you don’t realize it?

When it comes to mold ingestion, the most important thing to keep an eye out for is the danger of toxins that may be lurking within, according to Arun Bhunia, a Purdue University professor of food microbiology.

The mold itself might not be harmful, Bhunia says to Inverse. “However, the toxin it produces is harmful.”

Mycotoxins are mold-produced toxins that have been linked to liver cancer, and aflatoxins are a family of toxins produced by mold. According to Feng, mycotoxins are comparable to deadly snake venom in that they cause damage over a period of time rather than immediately.

Mycotoxins have a variety of negative consequences that occur over time. Bhunia believes that the negative side effects accumulate throughout time in the body. Mycotoxins may still be developing in your body even if you feel fine after eating a moldy slice of food.


Which Foods Can Be Contaminated With Mold?

Almost all foods can be moldy. However, certain foods are more likely to become moldy than others.

Fresh foods with a high water content are particularly susceptible to spoilage. Preservatives, on the other hand, limit mold development as well as the proliferation of microorganisms (2Trusted Source).

Mold can grow anywhere, including in your meals at home. It may develop during the growing, harvesting, storage, and processing stages of the food production process (2Trusted Source).

Common Foods That Can Grow Mold

Mold thrives on the following foods, which are common:

Strawberries, oranges, grapes, apples, and raspberries are among the fruits available.
Tomatoes, bell peppers, cauliflower, and carrots are among the vegetables.
Bread: Especially if it isn’t preserved
Cheese: Both soft and hard varieties

Other foods, such as meat, nuts, milk, and processed foods can also be infested with mold.

Since most mold require oxygen to survive, they will not grow where there is little available. Mold can establish on food that has been stored in airtight packaging after opening, however.

Most molds require moisture to survive, however xerophilic molds, which can grow in dry, sweet situations, are an exception. Chocolate, dry fruits, and baked goods (3Trusted Source, 4Trusted Source, 5Trusted Source) may sometimes be spotted with xerophilic molds.

Food may also be contaminated by bacteria. Mold can grow on and inside your food, not just on it. It’s possible for invisible germs to flourish alongside it.

Foodborne illnesses include nausea, diarrhea, and vomiting, which are all caused by bacteria. The kind of bacteria, the quantity consumed, and the individual’s health all play a role in determining how severe these illnesses are (1, 6).

So, when can you get sick from eating moldy bread?

It is important to remember that getting sick from moldy bread is possible, though uncommon, and that hearing that *most* instances of ingesting moldy bread will not cause you problems may be nice. Some individuals may be allergic to mold since it is a fungus.

Aranda claims that allergies to mold aren’t usually serious, but they have been known to be deadly in rare circumstances. The mycotoxins present in mold are another issue when it comes to eating it, aside from the allergy problem.

For the most part, if you consume a little bit once or twice, you’ll probably be fine, he adds. “These are chemicals certain molds create under particular circumstances that are harmful to humans and other animals.” They can become an problem when administered in higher doses or over longer periods of time.”

How to make your bread last longer

Of course, the best way to keep bread fresh for longer is to learn how to store it properly in the first place, which you can do by visiting a registered dietitian like Melissa Rifkin, RD.

Since bread boxes only allow a little amount of air to flow, they are perfect for keeping bread from forming mold. “Just make sure the location is not near a heat-producing appliance,” she advises. “When storing bread in a breadbox, cabinet, or drawer, just make sure you have enough counter space.”

Placing your bread near the stovetop or on top of a fridge that generates heat is a sure way to boost mold development, Rifkin claims.