Why should alcohol fermentation be carried out before making fruit vinegar?

First of all, the reasons are as follows:

Acetobacter used for vinegar brewing is Acetobacter, and glucose cannot be directly used. Moreover, glucose oxidizing bacteria can be directly utilized, and the efficiency of converting glucose into acetic acid is very low.

Therefore, in fermented vinegar, acetic acid is not directly fermented by sugar, but is produced by anaerobic fermentation of ethanol by Acetobacter.

Second, the principle of production

When oxygen and glycogen are sufficient, acetic acid bacteria decompose the sugar in grape juice into acetic acid.

When glycogen is deficient, Acetobacter converts ethanol into acetaldehyde, and then acetaldehyde is converted into acetic acid.

Extended data

Fruit vinegar contains more than ten kinds of organic acids and many kinds of amino acids needed by human body. Different kinds of vinegar have different contents of organic acids. Organic acids such as acetic acid contribute to the normal circulation of tricarboxylic acid in human body, so that aerobic metabolism is smooth, which is conducive to removing deposited lactic acid and relieving fatigue.

After a long period of labor and strenuous exercise, a lot of lactic acid will be produced in the human body, which makes people feel tired. If fruit vinegar is supplemented at this time, it can promote the recovery of metabolic function, thus eliminating fatigue.

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