Which statements are correct about the application of traditional fermentation technology?

The statement about the application of traditional fermentation technology is correct. Self-made fruit wine, fruit vinegar and sufu are usually not pure fermentation.

Data expansion:

Lactic acid bacteria are strict anaerobic bacteria, and their fermentation will be inhibited under aerobic conditions, so the process of making yogurt with lactic acid bacteria should be kept in a closed state, otherwise it will lead to fermentation failure.

In the process of making fruit vinegar, acetic acid bacteria produce carbon dioxide and water through aerobic respiration, and carbon dioxide dissolves in water to form carbonic acid. With the increase of carbon dioxide concentration, the pH value of the solution gradually decreased. In the process of making fruit wine, yeast produces carbon dioxide and alcohol through anaerobic respiration, and carbon dioxide dissolves in water to form carbonic acid. With the increase of carbon dioxide concentration, the pH value of the solution gradually decreased, so in the process of making fruit wine and fruit vinegar, the pH value of the solution gradually decreased.

The metabolic type of yeast for making fruit wine is heterotrophic and facultative anaerobic, and lactic acid bacteria for making yogurt belong to anaerobic bacteria, which can only reproduce under anaerobic conditions. The metabolic type of acetic acid bacteria for making fruit vinegar is heterotrophic and facultative aerobic. Sufu is fermented with tofu, and many microorganisms participate in the fermentation, among which Mucor plays a major role.

Mucor is a filamentous fungus with well-developed white hyphae. Proteinase produced by Mucor and other microorganisms can decompose protein in tofu into small peptides and amino acids. Lipase can hydrolyze fat into glycerol and fatty acids.