Fermentation

Dough fermenting.

Fermentation is the transformation of some organic substances by microorganisms generally called fermentors, each type of fermentor acts on a certain substance and produces its own fermentation. The microorganisms that cause fermentation are some types of bacteria and yeasts.

Many things can be fermented. In general, the product of fermentation is easier to digest, can be preserved for longer, or produces a desirable molecule, like alcohol in the case of alcoholic fermentation.

Much of the work on fermentation we owe to Louis Pasteur.

Other meaning of fermentation

Fermentation is a catabolic process of incomplete oxidation that does not require oxygen, the final product being an organic compound. These final products are what characterize the various types of fermentation.

Yeasts

The yeasts are responsible for several fermented products that a man enjoys. The scientific name of the yeast is Saccharomyceslo cerevisiae. It is a microscopic unicellular fungus. We put yeast in bread dough to inflate it and to make it lighter, because fermentation creates carbon dioxide and makes it spongy. Yeast can be used in the production of beer and to obtain an alcoholic beverage.

Types of fermentation

Lactic fermentation

This fermentation takes place in many organisms, and also in our muscles. When we do any muscular effort, for example running very fast, and there is insufficient supply of oxygen, fermentation occurs. Muscles use energy from sugar that is called glucose. Normally glucose is utilised in the presence of oxyegen and provides high energy to the cells. When the request of energy is urgent, the muscle doesn't have sufficient oxygen, and glucose fermentation produces lactic acid. This acid is responsible for the sharp cramping in the muscles after intense exercise.

Yogurt is a product obtained by the fermentation of milk. The fermentation of the lactose (the milk's sugar) in lactic acid is what gives the yogurt its texture and flavor.

Alcoholic fermentation

Some organisms are able to use sugar to produce ethyl alcohol. For this it must have a great quantity of sugar and no oxygen: as is the case in wine making. Baker's yeast also called brewer's yeast because it is capable of producing alcohol.

Why fermentation?

Fermentation is a medium that living organisms have for producing energy to live, even when there is little or no oxygen. Fermentation in chemical terms, is an incomplete oxidation. The majority of our body's cells are more or less capable to produce a fermentation.

Notes

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