By Karen Schneider Extension Food Safety Specialist University of Vermont Molds, a type of fungi, have been around for about three billion years. Requiring only minimal moisture and air, molds can grow almost anywhere, and very quickly. Molds perform many useful functions. They age and flavor cheeses. They are used in the production of soy sauce and penicillin.
Molds also manufacture the citric acid used to flavor soft drinks.
They can, however, be destructive. Molds hasten food spoilage and can cause allergic and respiratory problems. Some molds produce toxins that can be extremely harmful even in small amounts. Some toxins can survive a long time in food, and most are not destroyed by cooking. Mostly, though, molds affect the quality of food, causing discoloration, musty odors, and off-flavors.