Potassium metabisulfite (KMBS), also known as E224, is a white crystalline powder with a pungent sulfurous odor. It is commonly used in the food and beverage industry as a preservative and antioxidant. Here are some key points about its use in food:

Uses in Food Industry

1. Preservative: KMBS is widely used to inhibit the growth of bacteria, molds, and yeast in food products. It helps in extending the shelf life of various foods.
2. Antioxidant: It prevents oxidative discoloration and rancidity in food products, maintaining the appearance and flavor of the food.
3. Wine and Beer Making: It is commonly used in winemaking and brewing to prevent spoilage and oxidation. It helps in maintaining the color and flavor of the beverage and inhibiting unwanted microbial growth.
4. Dried Fruits and Vegetables: KMBS is used to preserve the color and prevent browning of dried fruits and vegetables.
5. Processed Foods: It is added to various processed foods, such as pickles, jams, and juices, to preserve freshness and extend shelf life.

Safety and Regulations

• Regulatory Status: KMBS is approved for use as a food additive by various regulatory agencies, including the FDA, EFSA, and WHO. However, its usage levels are regulated to ensure safety.
• Allergic Reactions: Some individuals, particularly those with asthma, may experience allergic reactions or sensitivity to sulfites, including potassium metabisulfite. Symptoms can include respiratory issues, skin reactions, and gastrointestinal problems.
• Maximum Permitted Levels: The maximum permitted levels of KMBS in food products vary by country and product type. Manufacturers need to comply with these regulations to ensure consumer safety.