Working principle of sodium metabisulfite preservative

Sodium metabisulfite is a commonly used preservative that can effectively extend the shelf life of food. The anti-corrosion effect of sodium metabisulfite is mainly achieved through the following aspects.

Sodium metabisulfite has a certain bactericidal effect. Sodium metabisulfite can react with bacteria, yeast, and molds in food, preventing their reproduction and growth. The main bactericidal mechanism of sodium metabisulfite is to kill microorganisms by releasing sulfur dioxide gas. Sulfur dioxide can damage the cell membrane and DNA structure of microorganisms, leading to their death.

Sodium metabisulfite can also inhibit oxidation reactions in food. Oxidation reaction is one of the main causes of food spoilage. Sodium metabisulfite can act as a reducing agent to react with oxygen in food, thereby slowing down the oxidation rate of food. Sodium metabisulfite can bind with free radicals in oxygen, preventing the destruction of nutrients and flavor substances in food by free radicals.

Sodium metabisulfite also has a certain antioxidant effect. Sodium metabisulfite can react with some oxidizing substances in food, thereby inhibiting its oxidation reaction. Sodium metabisulfite can combine with substances such as disaccharides, monosaccharides, and polysaccharides in food to form stable compounds and prevent their oxidation.

Sodium metabisulfite can also regulate the acidity and alkalinity of food. Sodium metabisulfite is an acidic substance that can create an acidic environment in food, thereby inhibiting the growth of bacteria and molds. Sodium metabisulfite can also neutralize alkaline substances in food, regulate the acid-base balance of food, and improve the stability and quality of food. It should be noted that although sodium metabisulfite has anti-corrosion properties, excessive or long-term use may have a certain impact on human health. The amount of sodium metabisulfite used in some foods should comply with relevant national standards to ensure food safety.

The anti-corrosion effect of sodium metabisulfite is mainly achieved through sterilization, inhibition of oxidation reactions, oxidation resistance, and adjustment of acidity and alkalinity. The correct use of sodium metabisulfite can extend the shelf life of food and maintain its quality and safety. However, it should be noted that sodium metabisulfite should be used reasonably and excessive use should be avoided to avoid adverse effects on human health.