Foodborne molds can endanger health, home and family. Hidden in pantry and fridge, these hardy survivors are unnoticed and dormant until conditions are right. Here are 16 foodborne molds, characteristics, health risks, practical management and some personal experience.
Mastering mold is crucial for keeping food safe. Foodborne molds are a diverse group of fungi. While some molds, like those used in cheese production, are beneficial, others can be harmful. Sometimes the same organism has dual inclinations.
Alternaria
Alternaria is commonly found in soil, plants and decaying leaves in nature, and can easily invade fruits, vegetables and grains. It appears as dark green or black patches and can cause significant spoilage. Up to 30% of tomatoes and carrots may be affected by this type of mold.
They prosper in damp, warm conditions. like most molds, While not typically associated with severe infections in healthy individuals, Alternaria can produce mycotoxins posing health risks, particularly in immunocompromised people.
Contaminated food can lead to allergic reactions, especially in sensitive persons. It can also produce harmful mycotoxins that may cause respiratory problems. To manage Alternaria, store fresh produce in a cool, dry place and regularly inspect items for any signs of spoilage.
Aspergillus
Aspergillus is often found in nuts, grains, seeds and spices. Its most famous variety, Aspergillus flavus, produces aflatoxins, potent carcinogens. About 5% of peanuts may contain unsafe levels of aflatoxin.
Several Aspergillus species are known for producing mycotoxins, particularly highly toxic aflatoxin. Proper storage and handling of foods can help prevent contamination. Consuming aflatoxin-contaminated food can cause serious liver damage and raise cancer risks over time.
Source food from reputable vendors. Store nuts and grains in airtight containers away from moisture.
Botrytis
Botrytis cinerea, or "grey mold," primarily affects fresh fruits and vegetables. It is responsible for an estimated 25% of post-harvest losses in crops like grapes, tomatoes and strawberries, appearing as a fluffy grey growth.
While it can lead to spoilage, it is also used beneficially in winemaking as "noble rot". However, in unsafe conditions it can cause gastrointestinal problems and illness.
In grocery stores berries often go moldy at the bottom of the package first, due to the moisture level. One trick of unscrupulous grocers is to remove non-moldy berries from packages containing moldy berries.
The non-moldy berries are then put in a fresh box with a new "packaged on" date. They look good, but are already infected with invisible microbes. It's important to shop at a trustworthy place. Checking condition of shelves, bins, etc also gives a clue as to store cleanliness.
Generally not harmful, Botrytis can carry other pathogens that may cause foodborne illnesses.
Inspect produce for signs of Botrytis before purchasing, and eat or store food promptly to minimize spoilage.
Cladosporium
Cladosporium loves the outdoors but can also infest stored grains and baked goods. It appears as olive-green patches, and is a common contaminant.
Cladosporium can lead to the spoilage of foods such as stored grains and fruits. While this mold is not commonly linked to serious health issues, it can trigger allergic reactions in sensitive people.
Primarily known for causing allergic reactions, certain Cladosporium species can produce mycotoxins, creating health risks. Keep pantry items dry and cool to deter Cladosporium growth. Regularly check for visible mold.
Fusarium
Fusarium species produce mycotoxins such as fumonisins, harmful to both humans and animals. Up to 5% of corn may be contaminated. Fusarium molds affect grains, cereals, and some fruits and vegetables.
This genus is infamous for mycotoxins such as fumonisins and trichothecenes, which can cause health problems ranging from gastrointestinal issues to long-term effects, including cancer. Proper agricultural practices are essential to combat Fusarium contamination.
Ingesting contaminated products can lead to gastrointestinal and neurological illness. Use airtight packaging for grains and ensure they are stored in dry conditions.
Geotrichum
Geotrichum is often found on dairy products and fruits, appearing as white mold. It can spoil dairy items. Geotrichum candidum is known for food spoilage and fermentation. In dairy products, fruits, and vegetables it leads to moldy taste and texture changes. Usually not harmful, it can occasionally cause infections in individuals with weakened immune systems.
Ensure proper refrigeration of dairy products and always check expiration dates. When an item says "packaged on (date)" this doesn't mean it's fresh, just that it's been repackaged.
Personal experience:
One trick of a local bad grocer was to take unsold chicken legs several days old, coat them with spices and put them back on the shelves as packaged that day. Even eaten right away they were often spoiled. So, watch out for unscrupulous food sellers like that one.
Once I found a bag of mold, which used to be oranges, under his fruit shelves. This mold was several weeks old at least. Orange peels take six month to decompose. Spores would have traveled to the fruit above and bread stored beside it. Needless to say, that grocer is no longer in business.
Monilia
The genus Monilia primarily affects stone fruits, causing brown rot, which leads to fruit decay. Infection can occur pre- and post-harvest, resulting in significant economic losses. While it does not pose serious health risks, consuming rotten fruit can lead to gastrointestinal distress.
Eating spoiled fruit can cause gastrointestinal discomfort and other mild reactions. Choose only fresh fruit and consume it in good time to prevent Monilia mold growth.
Manoscus
Manoscus is lesser-known but can appear in various food items. It is characterized by a greenish color and can affect the freshness of food. While not immediately harmful, Manoscus can spoil food and provoke allergic reactions. Regularly check food packaging and storage areas for any signs of mold growth.
Of the known species of this genus, the red-pigmented Monascus purpureus is among the most important. It's used in the production of certain fermented foods and beverages in East Asia, particularly China and Japan.
Monascus purpureus mold has been used for over a thousand years in fermented Asian foods. These include red kōji-kin, red yeast rice or ank-kak, rice wine, kaoliang brandy, and as the coloring agent for Peking duck.
Mortierella
Mortierella is often found in soil and decaying materials but can invade agricultural products. It may affect up to 10% of harvested crops. Though not commonly linked to human illness, some strains can cause allergic reactions. Ensure proper food storage and check stored food regularly.
Mortierella species are saprotrophs (decomposers) in soil, feeding on decaying leaves and other organic matter. Some species can be found on fecal pellets or the exoskeletons of arthropods. Penicillium, Trichoderma, Mucor, and Mortierella are part of an ecological group whose members are among the first organisms to colonize roots.
Mucor
Mucor loves humid conditions, appearing as white to greyish fluffy patches. Mucor species are found in soil, decaying organic matter and stored foods. They primarily affect grains, fruit and bread, causing visible spoilage.
Mucor can cause a range of health issues, particularly in immunocompromised individuals, including mucormycosis, a serious infection. This mold can lead to severe respiratory problems and allergic reactions. Keep storage areas dry to deter Mucor growth.
Mucormycosis is an uncommon severe fungal infection triggered by the mucormycete molds. The condition often affects people with compromised immune systems, typically manifesting in the sinuses or lungs. Mucormycosis can also develop on the skin following a cut or burn. If mucormycosis is suspected get treatment immediately.
Mucor mucedo loves cheese. It's sometimes called cat hair due to its long hairlike filaments.
Neurospora
Neurospora commonly affects bread, baked goods and fruit, recognizable by its bright orange color. It can spoil food quickly. Check for off-flavors or unattractive appearance of food. Do not consume moldy bread, as some strains produce mycotoxins.
It can lead to food spoilage and wastage. Cutting off moldy parts and eating the remainder is dangerous as the mold spores and filaments exist unseen in the body of the food. Molds also enjoy company, and in uncontrolled growths, different varieties are often present.
Store bread in a cool, dry place and seal tightly to prevent exposure to air. Know the nature of the foods. Blueberries can be refrigerated, as their full taste emerges after a cold snap in the wild. Peaches, however, lose all flavor in the fridge.
Eat promptly or, if they've been refrigerated, make them into jam or preserves to get back that delicious peachy taste. Flavor also makes a sweet and joyful return in peach sauces.
Neurospora as food: Oncom is a traditional staple food of Sundanese cuisine of Indonesia. The two kinds of oncom are red and black. Both types of oncom are fermented using mold. Red oncom is made with Neurospora intermedia var. oncomensis.
Oidium (Powdery Mildew)
Oidium is mainly associated with wine but can also grow on bread and other baked goods. It appears as a white substance also called powdery mildew. Oidium molds contaminate fruits and vegetables and are often responsible for crop damage in agriculture.
Although not usually harmful to humans, they can significantly reduce the aesthetic and nutritional quality of food. Oidium signals the deterioration of food quality. Inspect baked goods regularly.
In gardens and fields, powdery mildew can be treated with fungicides including potassium bicarbonate, neem oil, sulfur or copper. Home remedies like baking soda, dish soap or milk can also work. Be sure to wash/treat all plants in the vicinity of the infected one(s).
Oospora
Oospora frequently affect fruits and vegetables, appearing as fluffy white patches. It can result in significant food waste. Oospora are also less commonly found on stored grains and agricultural products.
They impact food quality by causing spoilage, but it aren't typically a major health concern.
Store fruits and vegetables in well-ventilated, dry areas to prevent mold growth.
Oospora, derived from Greek oón meaning 'egg' and spóros meaning 'seed', refers to a zygote enclosed by a dense cell wall. This structure functions as an endospore, which can sprout following a period of dormancy often due to harsh environmental circumstances.
Penicillium
Penicillium species are known for their uses in food production, notably in cheese making, and most famously in production of antibiotics. Specific strains can produce harmful mycotoxins, especially on grains and fruits.
Certain mycotoxins can lead to allergic reactions and foodborne illnesses. Consume fruit and dairy products quickly after purchase, and be alert for signs of mold.
Rhizopus
Rhizopus affects bread and fruits. Manifesting as white, fluffy growth, it darkens over time. It's estimated this mold affects around 10% of baked goods before sale. Rhizopus stolonifer is among the most common causes of bread mold.
This mold thrives on carbohydrates and can spoil diverse foods. While not typically associated with severe health issues, ingestion of Rhizopus can cause gastrointestinal illness and food poisoning. Store bread in a dry, cool place and consume before its expiration.
Thamnidium
Thamnidium is a lesser-known mold affecting grains and bread, appearing as white to greyish patches. It also forms on meat. Often overlooked, it can spoil food quickly.
Thamnidium is often found on decaying organic matter. While it is not associated with harmful effects on healthy individuals, it's a risk in terms of food wastage and quality. It can spoil food and trigger allergies in sensitive people.
Thamnidium molds are used in the maturation of dry-aged beef. By releasing protease and collagenase enzymes they help tenderize the meat naturally. These molds create light grey patches known as 'whiskers' on the fatty parts of a carcass or cut as they age.
However, Thamnidium, along with other fungal groups like Acremonium, Mucor, and Rhizopus, is linked to meat spoilage in cold storage.
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