Probably the earliest recorded usage of fermentation is for the purpose of making alcoholic drinks – for example, beer, wine or mead. These alcoholic beverages could have been made from as long ago as 7000 BC in some parts of the Middle East. Fermentation of other products like milk and vegetables is thought to have begun much later, happening concurrently both in China and the Middle East. Even though the main principles of fermentation can be applied to all foods and drinks, the exact way of achieving the results, and the final products, are different for each.
Fermentation in food processing typically is the conversion of carbohydrates to alcohols and carbon dioxide or organic acids using yeasts, bacteria, or a combination thereof, under anaerobic conditions. A more restricted definition of fermentation is the chemical conversion of sugars into ethanol. The science of fermentation is known as zymology
Fermentation usually implies that the action of microorganisms is desirable, and the process is used to produce alcoholic beverages such as wine, beer, and cider. Fermentation is also employed in preservation techniques to create lactic acid in sour foods such as sauerkraut, dry sausages, kimchi and yogurt, or vinegar (acetic acid) for use in pickling foods.
Food fermentation has been said to serve five main purposes:
- Enrichment of the diet through development of a diversity of flavors, aromas, and textures in food substrates
- Preservation of substantial amounts of food through lactic acid, alcohol, acetic acid and alkaline fermentations
- Biological enrichment of food substrates with protein, essential amino acids, essential fatty acids, and vitamins
- Elimination of anti-nutrients.
- A decrease in cooking times and fuel requirements
Out of all the preservation and preparation techniques, fermentation is the only type that does not destroy some nutrients, can create more, and enhance others. Omega 3 fatty acids, detoxifying agents and many B vitamins including folic acid, riboflavin, niacin, thiamin, and biotin are preserved through fermentation.
The improved digestibility of foods caused by fermentation allows for proper nutrient absorption. For example, the process transforms the sugar in dairy into lactic acid, a more tolerable form of lactose, allowing persons with an intolerance to stand fermented forms of dairy.
Fermentation Removes toxins and harmful bacteria found in many foods to resist potential infection and illness.