Chapter 9: Fermented and Microbial Foods

The key part played by micro-organisms in the production of fermented foods is in benign contrast to their role in foodborne illness. In this case, microbial activity can improve keeping quality, safety and the acceptability of a range of food materials. The yeasts and lactic acid bacteria are the most important organisms associated with fermented foods, being involved in the production of a plethora of breads, alcoholic beverages, fermented meat, dairy, plant and fish products. These two groups of organisms are discussed, particularly the lactic acid bacteria and their activities germane to their use in food fermentation. The production of fermented milks, cheeses, sauerkraut and kimchi, olives, cucumbers, fermented fish, meat, beer and vinegar are all described in detail, along with important mould fermentations used to produce tempeh, soy sauce and rice wine. The application of precision fermentation in the production of mycoprotein, single-cell protein and food additives, such as vitamins and amino acids, is also discussed.