Whether it is nature or conditioning, most humans are repelled by mold, especially on their food. We have all shared the unfortunate experience of uncovering some lost piece of fruit, jar of tomato sauce, or long forgotten leftovers at the back of the fridge only to discover our uncovering is actually covered in bluish-green fuzz. We try to handle it gingerly, having as little direct contact as humanly possible, but we always manage to get a little bit on our finger, or inadvertently touch a soft spot that feels like a sodden abyss. And mold, if left to its own devices, will certainly flourish, if not entirely colonize your fridge, pantry, or…gad…your entire kitchen. And in most cases, there is good reason to avoid and reject mold, as they signify the denaturing of the food, and they often carry toxins that could make you quite sick.
Still, for anyone that hasn’t been told, a good deal of the foods we eat are aided and cultivated by naturally occurring (and relatively benign) molds. Cheese, obviously being one of the more popular foods that is brought to maturity with the aid of surface molds and bacteria. The most notable being Penicillium notatum that brought the world penicillin. A relative of this form of Penicillin is Penicillium camemberti is added to the exterior of camembert and brie wheels to age them and create their white rinds, while Penicillium roqueforti gives blue cheeses such as stilton and roquefort their veins. There are also certain molds used to help age and flavor charcuterie and aged meats.
In essence, all food molds are parasitic by nature, and need a host to feast upon in order to thrive. Some molds, like the previously mentioned Penicillium camemberti and Muscodor albus, a fungus that emits gases, that protect grapes against another type of more nefarious mold called, Botrytis, are beneficial while others…not so much. And more often than not, consumers tend to overreact when there is a mold discovery in their kitchen. Many molds that grow upon cheese, preserves, and some fruits are utterly benign and can be cut away.
Does this mean we should, and could, just take it easy when we see mold? Yes and no, according to a BBC article on the topic. Impressively thorough advice from the US Department of Agriculture says you can rescue hard cheese and firm fruit and vegetables by cutting out at least an inch around and below the mould spot, but advises you to chuck out whiskery hot dogs, cooked meat, casseroles, grain and pasta, soft cheeses, yogurt, sour cream, jellies, soft fruit and vegetables, bread, baked goods, peanut butter, legumes, nuts and many more (be especially leery of peanut molds, as they can be horrendously toxic). 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.
To be on the safe side, unless it is a hard cheese, fruit or vegetable, you should likely discard the offending food, just as your intuition would tell you. And be sure to cut out/off any of the offending parts of the food before you take a big healthy bite of the food.