Inhibition of Browning by Sulfites

Abstract

The present state of understanding of the mechanisms by which sulfites inhibit browning reactions in food is reviewed. The difficulties of specifying the composition of sulfur(IV) oxospecies in sulfited foods arise from the existence of labile equilibria between S02' US0 3 -, 80 3 2 -and S2052-, whose position depends on concentration, ionic strength and the presence of non-electrolytes. A proportion of the additive is also found in a reversibly bound form. The main reason why sulfites are able to inhibit a wide range of browning reactions is the nucleophilic reactivity of sulfite ion.The mechanism of reactions between sulfite species and intermediates in the model Maillard browning reaction, glucose + glycine, are considered in depth and are supported by kinetic data. A most interesting feature is the fact that sulfites seem to catalyse the reactions they are added to control. Reaction products include 3,4-dideoxy-4-sulfohexosulose which is formed initially and polymeric substances arise from the reaction of sulfite species with melanoidins.

The Maillard reaction and food quality deterioration

“…Lipid oxidation products can also behave as carbohydrates reacting with amine-containing molecules. Besides the Maillard reaction, other nonenzymatic browning reactions also form colored polymers and fl avor compounds via a series of heat-catalyzed reactions including thermal oxidation of lipids, sugar-sugar interactions (caramelization) and ascorbic acid degradation (Nursten, 2005;Wedzicha et al, 1991).…”

Sulfites in meat: Occurrence, activity, toxicity, regulation, and detection. A comprehensive review

“…Mainly, there are two types of browning: enzymatic browning (EB) and nonenzymatic browning (NEB). Sulfites can stabilize, minimize, and inhibit various steps of both these processes (Ough & Were, 2005; Wedzicha, Bellion, & Goddard, 1991).…”

“…Differently from nitrites, sulfiting agents do not interact with myoglobin and hemoglobin, but indirectly stabilize oxygen binding forms. As a result, meat color and flavor are retained and the development of oxidative off‐flavors (rancidity) is delayed (Taylor et al., 1986; Wedzicha et al., 1991).…”

“…Sulfites can reduce and inhibit Maillard reaction forming sulfonates by reacting with carbonyl groups. Moreover, it was observed that SO 3 2− ions also attack glycosylamine and other intermediates, and act as terminators of polymers formation (van Boekel, 2006; Wedzicha, 1992; Wedzicha et al., 1991).…”

In vitro and in vivo inhibition of maillard reaction products using amino acids, modified proteins, vitamins, and genistein: A review

“…Sulfur dioxide is most frequently used as an inhibitor of browning in the form of sodium bisulfite or sodium metabisulfite. Sulfur dioxide is capable of inhibiting of MR by reversibly binding with the carbonylic intermediates formed during the initial stages of Maillard browning, and finally bleaching the brown color (Wedzicha, Bellion, & Goddard, ). However, sulfites could react with reducing sugars, carbonyl, and dicarbonyl compounds to form irreversible bonding at the time of inhibition of browning.…”