Antioxidant-antibrowning agents

In the food industry and in wine production, sodium metabisulfite is similarly used as an antioxidant, antimicrobial preservative, and antibrowning agent. However, at concentrations above about 550 ppm it imparts a noticeable flavor to preparations. 

Food additives can enhance the safety and nutritional quality of a food or vice versa. By preventing oxidation of fat and easily oxidized vitamins, antioxidants ensure that safety is enhanced and the intended nutritional value of the food is delivered. Antibrowning agents such as sulfite retain phytochemicals and vitamins A and C but lower the amount of thiamine, folate, and pyridoxal. Sorbic acid can prevent... 

G. Oms-Oliu, R. Soliva-Fortuny, O. Martin-Belloso, Edible coatings with antibrowning agents to maintain sensory quality and antioxidant properties of fresh-cut pears, Postharvest Biol Tec., 50 (1), 87-94,2008. 

Other antioxidants include sulfites, often added to wine and fruits as a preservative and antibrowning agent, and EDTA, which immobilizes metal ions that often catalyze oxidation reactions. The presence of sulfites in foods is usually labeled because some people (especially asthmatics) are allergic to them. 

Sulfites and EDTA are both antioxidants. Sulfites function as preservatives and antibrowning agents. EDTA acts to immobilize metal ions that catalyze oxidation reactions. 

I. Kubo, Q.-X. Chen, K.-I. Nihei, Molecular design of antibrowning agents antioxidative tyrosinase inhibitors. Food Chem. 81 (2003) 241-247. 

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