Understanding antioxidant mechanisms in preventing oxidation in foods

Many foods are becoming more susceptible to oxidative rancidity due to attempts to make foods healthier by increasing polyunsaturated fatty acids, and more sustainable by introducing light weight oxygen-permeable and light-penetrating packaging. Unfortunately, very few new food antioxidants have been made available over the past several decades and the use of synthetic antioxidants is disfavored by many consumers. Thus, in order to make natural, more sustainable and healthier foods, the food technologist must find ways to use existing antioxidants more effectively. This requires a strong understanding of antioxidant chemistry. This chapter reviews the chemistry of free radical scavengers, metal chelators, singlet oxygen quenchers and antioxidant enzymes. Interactions between antioxidants to enhance activity are also discussed.