Sodium metabisulfite is mainly used to prevent the blackening and spoilage of sea shrimp, and is a commonly used chemical reducing agent in fresh aquatic products. After fishing, fishermen often add it directly on fishing boats or transport boats. It is generally used more in summer, less in spring and autumn, and is basically not used in winter. Sodium metabisulfite is broken down into sulfur dioxide in aquatic products, which reacts with water to form sulfite. Sulfite has reducing properties and can effectively control browning in aquatic products, block microbial physiological oxidation processes, inhibit reproduction, inhibit food oxidase activity and chromophores, demonstrating its bleaching, decolorization, anti-corrosion, and antioxidant effects. The residual substance is sulfur dioxide (SO2), and sodium metabisulfite is specified in China’s “Hygienic Standards for Additive Use” for use in dried fruits, vegetables, fruit juice beverages, preserves, wine, etc. Its scope of use does not include aquatic products. Therefore, theoretically, sodium metabisulfite cannot be used in aquatic products, but in reality, fishing boats use this substance. But this substance is a shrimp preservative recommended by the United Nations, as well as a shrimp preservative recommended by countries and regions such as the United States, Japan, and Taiwan Province. Our local standard “Quality Requirements for Sea Shrimp ” also mentions the issue of limited use of sodium metabisulfite, so prohibiting its use is neither necessary nor feasible. The key is to prevent excessive use and harm to health. The excessive use of sodium metabisulfite is a common problem, and its use is mostly in the production process (fishing boats and transport ships), rather than in the processing plants and market processes. The residual limit of sulfur dioxide is 100mg/kg.

Application Status Of Sodium Metabisulfite In Aquaculture