Sulfur dioxide is a kind of food additive which is allowed to be used at home and abroad. It plays a role of preservation, antisepsis and oxidation resistance in food industry. SO2 is the only additive widely used in wine production. Its main functions in wine production are as follows:

1. Bactericide. Different microorganisms have different tolerance to SO2, among which bacteria are the most sensitive, followed by lemon type yeast and Saccharomyces cerevisiae. Therefore, SO2 can be used to select fermentation microorganisms.

2. Delay the start time of fermentation by inhibiting microbial activity.

3. Oxidation resistance, SO2 can inhibit the function of oxidase, prevent the raw materials from oxidation and mildew, and prevent the wine body from oxidation and discoloration.

4. Increase the acidity and adjust the fermentation substrate to reach the appropriate acidity.

 

 

Reasonable use of sulfur dioxide has a positive effect on the quality of wine

1. Purify fermentation substrate and improve wine alcohol.

2. Increase the content of organic acid and decrease the content of volatile acid.

3. Increase color

4. improve the taste quality of the wine (remove mold, clay, vinegar and oxidizing flavor, and maintain fruit flavor).

In view of the great role of SO2 in wine production, the process environment is strictly controlled in wine research and production practice. At the same time, we are actively looking for alternatives. Unfortunately, for hundreds of years, the production process has developed to today, and no better alternative has been found. The sulfur dioxide content in wine is far lower than that in some packaged food, even preserved fruit. The wine produced by regular manufacturers will add SO2 according to the prescribed amount, which will not produce health impact on human body, so it can be safely drunk.

Sulfur dioxide has the following functions in wine production

1. Fresh keeping, anti-oxidation, preservative. Adding sulfur dioxide before grape harvest and fermentation can prevent the juice from partially oxidizing. After fermentation, sulfur dioxide should be added to the wine when it is still in the fermentation tank. When bottling for sale, in order to sterilize, resist oxidation and prevent liquor from deterioration, it is also necessary to have a proper amount of sulfur dioxide in the bottle

2. In the process of strengthening wine brewing, adding sulfur dioxide can stop fermentation. If the sulfur dioxide content is too high, it will have pungent smell. For example, the smell of match just struck is slightly higher, which will cover up the fresh fruit flavor of wine, and the lack of sulfur dioxide content will lead to wine oxidation. Therefore, the addition of sulfur dioxide in wine is strictly regulated by law, which needs to be strictly controlled.

In addition, a very small number of people will be allergic to sulfur dioxide, even if the natural sulfur dioxide produced during grape fermentation will still have the same effect.