The whole world talks about fermentation, but what is it, really?
The term “fermentation” comes from the Latin “fervere” which refers to the boiling of the must during the preparation of wine. So many of the foods that we all know owe their nature to this ancient process. Some names? Beer, yogurt, bread, cheese, coffee, chocolate.
Fermentation is a useful metabolic route to preserve food. Indeed, during this process some microorganisms act on sugars transforming them into compounds with a conservative action.
At a chemical-physical level, organic matter, usually carbohydrates, is demolished to produce energy in the form of a molecule called adenosine triphosphate (ATP) along with other useful substances. This molecule is what allows the survival of food, implementing all the processes necessary to keep it alive. That’s why fermentation is connected to life, and fermented food is live food.
Oxygen plays a key role in this area: depending on whether or not there is oxygen in the production of energy, the difference between aerobic and anaerobic fermentation is determined. The first takes place thanks to the intervention of oxygen present in the air that causes an oxidation process; the second occurs without oxygen as a receptor and takes place in two rapid times in which energy is released and with it waste substances that can be acidic or alcoholic.
Now that we have understood more, it is interesting to study what changes in the organoleptic composition of food. In addition to the changes immediately perceptible to the naked eye – those that our senses help us to fully understand such as the thickening of milk that becomes yogurt and the increase in the volume of bread during leavening – there are many other transformations at the organoleptic and nutritional level that it is necessary to study more closely. Deep down, the fermented food changes a lot: the microorganisms present ally with each other and carry out a predigestion of the food, while the new microorganisms that come to life together with the fermentation process have the function of making our diet more complete. These are vitamins, especially from group B (riboflavin, folic acid, niacin, etc.) and enzymes that make proteins and starches more digestible and increase the presence of antioxidant substances.
In general, the environment created during the fermentation process makes the food inhospitable for competing bacteria such as those responsible for food poisoning such as salmonella. The main feature of this process, which undoubtedly makes it unique and magical, is its ability to prolong food’s shelf life that would otherwise be more easily perishable. In addition, it also changes the duration and availability of nutrients and preserves them for longer making them even more absorbable by the human organism.
Depending on the resulting foods, we can see different types of fermentation. Below are just a few of the most common ones that we will delve into later in the next articles:
Alcoholic fermentation, which is used for the production of alcoholic beverages, bread, leavened foods, and bio-fuels. It takes place thanks to the action of yeasts and bacteria that produce ethanol and carbon dioxide.
Lactic fermentation, which, starting from glucose, produces lactic acid or lactic acid and acetic acid for the production of yogurt and derivatives.
Malolactic fermentation, after alcoholic fermentation, is responsible for the maturation of wine.
Acetic fermentation, used for the production of vinegar, is an oxidation reaction through which ethanol is transformed into acetic acid.
