Subsurface mold growth in food

Mold is a fungus that produces a fuzzy, cobweblike growth on moist materials, including food.  Black bread mold, Aspergillus niger, is one of the most familiar molds. Molds are found nearly everywhere in the environment.  When present in fresh or processed foods, molds may grow and cause an unsightly appearance and off-flavors.

In addition, some molds are capable of producing mycotoxins which are hazardous to human health. Most products will allow only mold growth due to low aw. Molds must have a warm, moist environment, oxygen, some light and food to produce their spores.

Most molds grow well on starchy foods (bread), the rind of some fruit such as lemons and oranges.

Sulfur dioxide is broadly effective again yeasts and molds. It is used extensively to control growth of undesirable microorganism in fruits, fruit drinks, wines, sausages, fresh shrimp and pickles.
Subsurface mold growth in food