Molds On Food: Are They Dangerous? usda

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Molds On Food: Are They Dangerous?

http://www.fsis.usda.gov/FactSheets/Molds_On_Food/

What Are Molds?

Are Some Molds Dangerous?

Are Molds Only on the Surface of Food?

Where Are Molds Found?

What Are Some Common Foodborne Molds?

What Are Mycotoxins?

What is Aflatoxin?

How Does the U.S. Government Control Aflatoxins?

Is Mushroom Poisoning Caused by Molds?

Are Any Food Molds Beneficial?

Why Can Mold Grow in the Refrigerator?

How Can You Minimize Mold Growth?

Don't Buy Moldy Foods

Must Homemade Shelf-Stable Preserves be Water-Bath Processed?

How Can You Protect Food from Mold?

How Should You Handle Food with Mold on It?

Some molds cause allergic reactions and respiratory problems. And a few molds,

in the right conditions, produce " mycotoxins, " poisonous substances that can

make people sick. When you see mold on food, is it safe to cut off the moldy

part and use the rest? To find the answer to that question, delve beneath the

surface of food to where molds take root.

What Are Molds?

Molds are microscopic fungi that live on plant or animal matter. No one knows

how many species of fungi exist, but estimates range from tens of thousands to

perhaps 300,000 or more. Most are filamentous (threadlike) organisms and the

production of spores is characteristic of fungi in general. These spores can be

transported by air, water, or insects.

Unlike bacteria that are one-celled, molds are made of many cells and can

sometimes be seen with the naked eye. Under a microscope, they look like skinny

mushrooms. In many molds, the body consists of:

root threads that invade the food it lives on,

a stalk rising above the food, and

spores that form at the ends of the stalks.

The spores give mold the color you see. When airborne, the spores spread the

mold from place to place like dandelion seeds blowing across a meadow.

Molds have branches and roots that are like very thin threads. The roots may be

difficult to see when the mold is growing on food and may be very deep in the

food. Foods that are moldy may also have invisible bacteria growing along with

the mold.

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Are Some Molds Dangerous?

Yes, some molds cause allergic reactions and respiratory problems. And a few

molds, in the right conditions, produce " mycotoxins, " poisonous substances that

can make you sick.

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Are Molds Only on the Surface of Food?

No, you only see part of the mold on the surface of food -- gray fur on

forgotten bologna, fuzzy green dots on bread, white dust on Cheddar, coin-size

velvety circles on fruits, and furry growth on the surface of jellies. When a

food shows heavy mold growth, " root " threads have invaded it deeply. In

dangerous molds, poisonous substances are often contained in and around these

threads. In some cases, toxins may have spread throughout the food.

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Where Are Molds Found?

Molds are found in virtually every environment and can be detected, both indoors

and outdoors, year round. Mold growth is encouraged by warm and humid

conditions. Outdoors, they can be found in shady, damp areas or places where

leaves or other vegetation are decomposing. Indoors, they can be found where

humidity levels are high.

Molds form spores which, when dry, float through the air and find suitable

conditions where they can start the growth cycle again.

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What Are Some Common Foodborne Molds?

Molds most often found on meat and poultry are Alternaria, Aspergillus,

Botrytis, Cladosporium, Fusarium, Geotrichum, Monilia, Manoscus, Mortierella,

Mucor, Neurospora, Oidium, Oosproa, Penicillium, Rhizopus and Thamnidium. These

molds can also be found on many other foods.

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What Are Mycotoxins?

Mycotoxins are poisonous substances produced by certain molds found primarily in

grain and nut crops, but are also known to be on celery, grape juice, apples,

and other produce. There are many of them and scientists are continually

discovering new ones. The Food and Agriculture Organization (FAO) of the United

Nations estimates that 25% of the world's food crops are affected by mycotoxins,

of which the most notorious are aflatoxins.

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What is Aflatoxin?

Aflatoxin is a cancer-causing poison produced by certain fungi in or on foods

and feeds, especially in field corn and peanuts. They are probably the best

known and most intensively researched mycotoxins in the world. Aflatoxins have

been associated with various diseases, such as aflatoxicosis in livestock,

domestic animals, and humans throughout the world. Many countries try to limit

exposure to aflatoxin by regulating and monitoring its presence on commodities

intended for use as food and feed. The prevention of aflatoxin is one of the

most challenging toxicology issues of present time.

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How Does the U.S. Government Control Aflatoxins?

Aflatoxins are considered unavoidable contaminants of food and feed, even where

good manufacturing practices have been followed. The U.S. Food and Drug

Administration and the USDA monitor peanuts and field corn for aflatoxin and can

remove any food or feed with unacceptable levels of it.

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Is Mushroom Poisoning Caused by Molds?

No, it is due to the toxin produced by the fungi, which are in the same family

as molds. Mushroom poisoning is caused by the consumption of raw or cooked

mushrooms, which are higher-species of fungi. The term " toadstool " (from the

German " Todesstuhl " -- death's stool) is commonly given to poisonous mushrooms,

but there is no general rule of thumb for distinguishing edible mushrooms from

poisonous toadstools. The toxins that cause mushroom poisoning are produced

naturally by the fungi. Most mushrooms that cause human poisoning cannot be made

safe by cooking, canning, freezing, or any other processing. The only way to

avoid poisoning is not to eat poisonous mushrooms.

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Are Any Food Molds Beneficial?

Yes, molds are used to make certain kinds of cheeses and can be on the surface

of cheese or be developed internally. Blue veined cheese such as Roquefort,

blue, Gorgonzola, and Stilton are created by the introduction of P. roqueforti

or Penicillium roqueforti spores. Cheeses such as Brie and Camembert have white

surface molds. Other cheeses have both an internal and a surface mold. The molds

used to manufacture these cheeses are safe to eat.

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Why Can Mold Grow in the Refrigerator?

While most molds prefer warmer temperatures, they can grow at refrigerator

temperatures, too. Molds also tolerate salt and sugar better than most other

food invaders. Therefore, molds can grow in refrigerated jams and jelly and on

cured, salty meats -- ham, bacon, salami, and bologna.

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How Can You Minimize Mold Growth?

Cleanliness is vital in controlling mold. Mold spores from affected food can

build up in your refrigerator, dishcloths, and other cleaning utensils.

Clean the inside of the refrigerator every few months with 1 tablespoon of

baking soda dissolved in a quart of water. Rinse with clear water and dry. Scrub

visible mold (usually black) on rubber casings using 3 teaspoons of bleach in a

quart of water.

Keep dishcloths, towels, sponges, and mops clean and fresh. A musty smell means

they're spreading mold around. Discard items you can't clean or launder.

Keep the humidity level in the house below 40%.

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Don't Buy Moldy Foods

Examine food well before you buy it. Check food in glass jars, look at the stem

areas on fresh produce, and avoid bruised produce. Notify the store manager

about mold on foods!

Fresh meat and poultry are usually mold free, but cured and cooked meats may not

be. Examine them carefully. Exceptions: Some salamis -- San Francisco, Italian,

and Eastern European types -- have a characteristic thin, white mold coating

which is safe to consume; however, they shouldn't show any other mold. Dry-cured

country hams normally have surface mold that must be scrubbed off before

cooking.

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Must Homemade Shelf-Stable Preserves be Water-Bath Processed?

Yes, molds can thrive in high-acid foods like jams, jellies, pickles, fruit, and

tomatoes. But these microscopic fungi are easily destroyed by heat processing

high-acid foods at a temperature of 212 °F in a boiling water canner for the

recommended length of time. For more information about processing home-canned

foods, go to the National Center for Home Food Preservation at:

www.uga.edu/nchfp/.

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How Can You Protect Food from Mold?

When serving food, keep it covered to prevent exposure to mold spores in the

air. Use plastic wrap to cover foods you want to stay moist -- fresh or cut

fruits and vegetables, and green and mixed salads.

Empty opened cans of perishable foods into clean storage containers and

refrigerate them promptly.

Don't leave any perishables out of the refrigerator more than 2 hours.

Use leftovers within 3 to 4 days so mold doesn't have a chance to grow.

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How Should You Handle Food with Mold on It?

Buying small amounts and using food quickly can help prevent mold growth. But

when you see moldy food:

Don't sniff the moldy item. This can cause respiratory trouble.

If food is covered with mold, discard it. Put it into a small paper bag or wrap

it in plastic and dispose in a covered trash can that children and animals can't

get into.

Clean the refrigerator or pantry at the spot where the food was stored.

Check nearby items the moldy food might have touched. Mold spreads quickly in

fruits and vegetables.

See the attached chart " Moldy Food: When to Use, When to Discard. "

Molds on Food

FOOD HANDLING REASON

Luncheon meats, bacon, or hot dogs Discard Foods with high moisture content can

be contaminated below the surface. Moldy foods may also have bacteria growing

along with the mold.

Hard salami and dry-cured country hams Use. Scrub mold off surface. It is normal

for these shelf-stable products to have surface mold.

Cooked leftover meat and poultry Discard Foods with high moisture content can be

contaminated below the surface. Moldy foods may also have bacteria growing along

with the mold.

Cooked casseroles Discard Foods with high moisture content can be contaminated

below the surface. Moldy foods may also have bacteria growing along with the

mold.

Cooked grain and pasta Discard Foods with high moisture content can be

contaminated below the surface. Moldy foods may also have bacteria growing along

with the mold.

Hard cheese

(not cheese where mold is part of the processing) Use. Cut off at least 1 inch

around and below the mold spot (keep the knife out of the mold itself so it will

not cross-contaminate other parts of the cheese). After trimming off the mold,

re-cover the cheese in fresh wrap. Mold generally cannot penetrate deep into the

product.

Cheese made with mold

(such as Roquefort, blue, Gorgonzola, Stilton, Brie, Camembert) Discard soft

cheeses such as Brie and Camembert if they contain molds that are not a part of

the manufacturing process. If surface mold is on hard cheeses such as Gorgonzola

and Stilton, cut off mold at least 1 inch around and below the mold spot and

handle like hard cheese (above). Molds that are not a part of the manufacturing

process can be dangerous.

Soft cheese

(such as cottage, cream cheese, Neufchatel, chevre, Bel Paese, etc.) Crumbled,

shredded, and sliced cheeses (all types) Discard Foods with high moisture

content can be contaminated below the surface. Shredded, sliced, or crumbled

cheese can be contaminated by the cutting instrument. Moldy soft cheese can also

have bacteria growing along with the mold.

Yogurt and sour cream Discard Foods with high moisture content can be

contaminated below the surface. Moldy foods may also have bacteria growing along

with the mold.

Jams and jellies Discard The mold could be producing a mycotoxin.

Microbiologists recommend against scooping out the mold and using the remaining

condiment.

Fruits and vegetables, firm

(such as cabbage, bell peppers, carrots, etc.) Use. Cut off at least 1 inch

around and below the mold spot (keep the knife out of the mold itself so it will

not cross-contaminate other parts of the produce). Small mold spots can be cut

off fruits and vegetables with low moisture content. It's difficult for mold to

penetrate dense foods.

Fruits and vegetables, soft

(such as cucumbers, peaches, tomatoes, etc.) Discard Fruits and vegetables with

high moisture content can be contaminated below the surface.

Bread and baked goods Discard Porous foods can be contaminated below the

surface.

Peanut butter, legumes and nuts Discard Foods processed without preservatives

are at high risk for mold.