What is Fermentation ?
A potable liquid containing ethyl alcohol or ethanol (C2H5O5) of 0.5% or more by volume is termed as as "alcoholic beverage ". Alcohol is obtained by fermenting a liquid containing Sugar. Fermentation is the process in which the yeast acts on sugar and convert it to ethanol and gives off carbon dioxide.
Fermentation:-
Fermentation is the process in which sugar is converted to alcohol and carbon dioxide by yeast. This process is the basis for producing all types of alcoholic beverages.
The alcohol level of fermented drinks is normally between 3-14% ,depending on the amount of sugar present in the liquid. Once the alcohol level reaches 14% ,the yeast gets killed, thus bringing the
fermentation process to halt. Example of fermented drinks are wine,beer,cider and perry. The CO2 released during fermentation is either allow to escape or in absorbed into the liquid to give effervescence. Example are sparkling wine, sparkling ciders, and beers.
The following are necessary for fermentation to take place:-
1)Sugar 2)Yeast 3) Temperature.
In the absence of any of these ,fermentation will not occur.
Brewed and Fermented Drinks:-
It is similar to fermented drink but the only difference is that the base ingredient ,Which is usually malted and crushed cereal ,is brewed in hot water to extract maximum soluble sugar from the malt. It is then cooled,and allowed to ferment which the addition of yeast .
Beer and sake are examples for this category.
Sugar:-
It is one of the most important materials required for fermentation. Yeast acts on sugar and once molecules of sugar to two molecules of ethyl alcohol and two molecules of Carbon dioxide . Some of natural liquids have adequate sugar content which is converted to alcohol .For example , Fruit juice have natural sugars and they are fermented by the action of yeast.
The juices and the corresponding alcoholic drinks obtained by the fermenting them are in the following .
- Grape juice :- Wine
- Apple juice :- Cider
- Pear juice :- Perry
Yeast :-
It is single-called Organism, essential for fermentation. Yeast is found in huge quantities in the soil, plants and air. The following types of yeast are used in fermentation process ,the type chosen dictates the profile of the fermented drinks.
1)Ambient or Natural yeast 2)Cultured Yeast
Ambient yeast are the ones that are found in the air,fruits,grains ,soil ,etc. They include all kind of natural yeast .Wild yeasts are present in vineyard and especially on the skin of grapes. The most common species of wild yeasts are-"Hansenula","Klockera ","Pichia" or "Tarulopsis".
TEMPERATURE :-
An ideal temperature is necessary for the yeast to act on the sugar . Throughout the process,the temperature of fermenting liquid should be controlled. Fermentation occurs in the temperature range of 3-32 ° C ( 38-90° F).
0 Comments
Please don't enter any spam link in the comment box .