Sodium chloride inhibits the heat-induced formation of advanced glycation end-products in myofibrillar protein-reducing sugar-oleic acid model systems

This research aimed to investigate the effects of sodium chloride (NaCl) on the formation of N epsilon-carboxymethyllysine (CML) and N epsilon-carboxyethyllysine (CEL), in pork myofibrillar protein (MFP)-reducing sugar (glucose or ribose) systems (with or without oleic acid) during commercial sterilization (121 degrees C, 10 min). The addition of NaCl (1% or 2%) in all tested model systems (MFP and MFP-glucose systems with or without oleic acid, and MFP-ribose-oleic acid system), except for the MFP-ribose system, resulted in less heat-induced production of CML and CEL. Although the addition of oleic acid in MFP or MFP-sugar systems without NaCl generally promoted the formation of CML and CEL during heating, the heat-induced production of CML and CEL in MFP-sugar-oleic acid-NaCl systems were much lower than that in their MFP-sugar-NaCl counterparts. This implies that the presence of NaCl could alter the general promoting effect of lipid oxidation on the formation of advanced glycation end-products in protein-reducing sugar systems, which may be due to the effects of NaCl on the roles of free radicals playing in the autoxidation of reducing sugars as well as in the Maillard reaction.