What are the applications of antioxidants in food?

Antioxidants as food additives can help fight food spoilage. Exposure to air and sunlight are two of the biggest factors in food oxidation, so store food in an airtight container, away from light, or in a wax-coated package like a cucumber. However, oxygen is also important for the respiration of plants, which produce unpleasant odors and colors when stored in an anaerobic environment, so fresh fruits and vegetables are generally stored at 8% oxygen. Antioxidants are an important class of preservatives. Unlike food spoilage caused by bacteria and fungi, frozen or frozen foods can still be oxidized relatively quickly. These antioxidant preservatives include natural vitamin C and vitamins as well as synthetic propyl gallate, TBHQ, BHT and Butylated hydroxyanisole. Unsaturated fat are the most common molecules that are subject to oxidation, which causes them to rancidity. It is important to prevent the oxidation of fatty foods because oxidized lipids change color and produce a metallic or sulfur-like flavor. These fatty foods are therefore rarely stored by air-drying and are instead stored by smoking, salting or fermentation. Even low-fat foods such as fruits are sprayed with sulfur-containing antioxidants before being air-dried. Oxidation reactions often require metal catalysis, which is why fats like butter are never wrapped in aluminum foil or stored in metal containers. Some fatty foods, such as olive oil, can partially avoid oxidation because they contain natural antioxidants, but are still sensitive to photooxidation. Some lipid cosmetics, such as lipsticks and moisturizers, also need antioxidant preservatives to avoid rancidity.