Is wine with sulfur dioxide added, safe?

□ Shu Jianyu

There are many types of wines, and we will find an unpleasant ingredient on the ingredient list of some wines, that is, sulfur dioxide. What is sulfur dioxide? Does wine with sulfur dioxide added to it affect health? Today, the author takes you to "taste" the wine with sulfur dioxide added.

Application of sulfur dioxide in food

Sulfur dioxide is a colorless, transparent gas, a toxic gas with a pungent odor that people with heart disease and respiratory diseases are most sensitive to. After sulfur dioxide enters the respiratory tract, because it is easily soluble in water, most of it is blocked in the upper respiratory tract, and corrosive sulfurous acid, sulfuric acid and sulfate are generated on the moist mucous membrane, which enhances the stimulation effect. Sulfur dioxide can be absorbed into the bloodstream, which has toxic side effects on the whole body, it can destroy the vitality of enzymes, thereby significantly affecting the metabolism of carbohydrates and proteins, and has certain damage to the liver.

So, why do you use sulfur dioxide in food processing? Because sulfur dioxide substances can form sulfurous acid, sulfurous acid has bleaching and preservative effects on food. Sulfur combustion produces sulfur dioxide, which forms sulfurous acid when exposed to water. Sulfites react with acids to produce sulfur dioxide, which forms sulfurous acid when exposed to water. Sulfurous acid is a strong reducing agent, when oxidized, the colored substances can be reduced and faded, so that the food remains bright color, but also inhibits the oxidase in the food, to prevent food browning. Because of its reducing effect, it can also block the normal physiological oxidation process of microorganisms and inhibit the reproduction of microorganisms, thus playing an antiseptic effect. Therefore, sulfur dioxide substances are commonly used bleaching agents and preservatives in food processing.

The role of sulfur dioxide in wine

Sulfur dioxide is the only additive commonly used in wine production, with four main effects. The first is selective sterilization. As a fungicide, the tolerance of different microorganisms to sulfur dioxide is different, of which bacteria are the most sensitive and are killed first after adding sulfur dioxide; followed by lemon yeast; Saccharomyces cerevisiae has a strong tolerance to sulfur dioxide. Therefore, fermentation microorganisms can be selected by sulfur dioxide. The second is the role of clarification. By inhibiting microbial activity, the start time of fermentation is delayed, which facilitates the precipitation of suspended solids in the fermentation matrix. The third is antioxidant effect. Sulfur dioxide can act as an inhibitor of oxidase, prevent oxidation of raw materials, and some other wine diseases. The fourth is to increase acid and adjust the fermentation matrix to reach a suitable acidity.

The rational and appropriate use of sulfur dioxide can have a considerable degree of positive effect on the composition and quality of wine: purify the fermentation matrix and improve the wine content; increase the organic acid content; reduce the volatile acid content; increase the color; improve the taste quality of the wine - alleviate the musty, earthy, vinegar and oxidative taste.

Effects of wine with added sulfur dioxide on human health

If the amount of sulfur dioxide substances is not mastered in the food processing process, or some enterprises in order to pursue their products with good appearance and color, extend the shelf life of food, cover up the quality of inferior food, regardless of standard restrictions, excessive use of sulfur dioxide additives, it is possible to cause the residual amount of sulfur dioxide in food to exceed the national standard (GB 2760-2014 wine limit is ≤0.25g /L), thus causing certain adverse effects on human health.

Although sulfur dioxide has a great effect on the wine making, it cannot be ignored that when the sulfur dioxide content is too high, the wine will produce a bad smell like rotten eggs, which will cause acute poisoning after drinking, and may also cause pulmonary edema, ventricular breathing, and coma. Therefore, the sulfur dioxide content in wine has always belonged to the testing items that should be strictly monitored in wine testing.

The sulfur dioxide contained in the commercially available wine is far lower than the national standard, after the wine is opened, 30%-40% of the sulfur dioxide in the wine will disappear due to the combination with oxygen, and eventually only a trace amount of sulfur dioxide will enter the human body, so drinking a moderate amount of wine with sulfur dioxide should be harmless to the human body.

When we select wine, we should check whether the labeling and labeling of the wine are complete and accurate, whether it meets the national food safety standards, and try to select quality assurance brands produced and sold through formal channels.

(Author Affilications:Hubei Institute of Product Quality Supervision and Inspection)

Author: Shu Jianyu

Source: China Quality News