Term in biology for the microbial or enzymatic conversion of organic substances into acid, gases or alcohol. It is derived from the Latin "fermentum" for sourdough or fermentation. Originally, it was understood to mean the biological reaction in the absence of oxygen, which the natural scientist Louis Pasteur (1822-1895) described as follows: Fermentation, c'est la vie sans l'air. Nowadays, any technical bioreaction is understood under the umbrella term fermentation. Enzymes (ferments), yeasts or fungal organisms are responsible for fermentation. They are specifically added (inoculated) with desired properties. In some cases, these microorganisms are already naturally present on the starting materials, such as the grapes, already in the vineyard, which is used in spontaneous fermentation (without the use of cultivated yeasts).
Fermentation, on the other hand, is usually understood as the microbial degradation of organic substances without the inclusion of external electron acceptors such as oxygen(anaerobic) for the purpose of energy production. However, the degradation of organic substances can also take place with the inclusion of oxygen (aerobic). For example, in acetic acid fermentation, oxygen is consumed, which is why this is not a fermentation in the scientific sense. In German, the term fermentation is an umbrella term for all aerobic and anaerobic processes. This often leads to confusion because in other languages "fermentation" is also used for alcoholic fermentation or there is no separate term for it.
Examples of fermentation processes are the transformation of dough into bread, milk into cheese or yoghurt, cabbage into sauerkraut, meat into salami and wine into vinegar. Fermentative processes also play an important role in the production of beer, as well as in numerous spirits such as brandies, sake (rice wine), tequila, whisky and vodka. During fermentation, the highly toxic ethyl carbamate can be formed as a by-product. In the pharmaceutical industry, special fermentation processes are used to produce drugs such as insulin and penicillin. See also under winemaking.
