However, not all foods can cause foodborne illness. For example, an overripe pear is soft, mushy and very unappealing, but it would not be unsafe to eat. Some microorganisms are used for a desirable change in foods. Yeasts are used in bread and wine making. Certain bacteria are required to make sauerkraut or to sour milk.
Molds are a part of ripening of some cheeses.
Foodborne illnesses are caused by pathogenic microorganisms, which include viruses, yeasts, molds and bacteria, including salmonella sp. and staphylococcus aureus . There are also some parasites that can be found in some foods that may be dangerous, as trichinella spiralis . Certain conditions need to be present before a food can carry a foodborne illness. Inappropriate food handling practices are used. Time-temperature combinations are such that microorganisms will grow in foods.