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What is the alcoholic fermentation?

The alcoholic fermentation (or ethylic fermentation) is a biological process of fermentation incomplete absence of air (oxygen), started by the activity of some microorganism that prosecute the carbohydrates (in general rule sugared: such as glucose, fructose, sucrose and starch, etc) to obtains as a final products an alcohol in form of ethanol, carbon dioxide (CO2) in form of gas and some particles of ATP that consume its own microorganism in its anaerobic, cellular energy metabolism.
The ethanol resultant of the alcoholic fermentation is used in the elaboration of several spirit drinks like the wine, beer, cider, cava…
The alcoholic fermentation has as a biological finality to proportionate anaerobic energy to the unicellular microorganisms (yeasts) in absence of oxygen. For this reason the molecules dissociate the glucose and they obtain the enough energy to survive, producing alcohol and CO2 as a result of the fermentation waste.
One of the main characteristics of these microorganisms is that living environments completely devoid of oxygen (O2), especially during the chemical reaction. For this reason it said that the alcoholic fermentation is an anaerobic process.
Ancestral discovery
The humanity used the alcoholic fermentation since time immemorial to elaborate beer (using cereals) and from the wine (using the fruit of the vineyard: the grape in juice form) essentially.
The alcoholic fermentation of the wine is very old and even in the Bible there are many references to the process.
Wine fermentation
The wine fermentation is the best known. The responsible yeasts of the vinification are microscopic funguses that is located in a natural way in the skins of the grapes (generally in form of a fine white dust that covered the grape skin (Vitis vinifera) and it is denominated “bloom” (Pruina).
The elaboration of the wine has an alcoholic fermentation of the fruit of the vineyard in stainless steel tanks which is denominated tumultuous fermentation due to the high boiling that occurs during a period between 10 and 14 days proximally.
After the main fermentation in the wine industry it is often referred to the second fermentation that it produced in other tanks used in the racking of the young wine (As it can be in the bottle of the wine). White wines ferment at a relatively low-temperatures between 10º and 15º C and the red wines at a higher temperature between 20º and 30º C.

Sometimes, the ethylic fermentation is stops voluntary for several reasons:
• One of the more usual is that density has reached the statutory alcohol.
• In other cases, on the other hand it is activated in a voluntary way the ferment process because the addiction of the sugared materials.
This second phenomenon is called of chaptalisation and it is very regulate in wine producers countries.

Source: Wikipedia.


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