Formation and decomposition of 3-chloropropane-1,2-diol esters in models simulating processed foods

Abstract

The formation of 3-chloropropane-1,2-diol (3-MCPD) released from its esters with higher fatty acids was studied using the recognised precursors of 3-MCPD (tripalmitin, 1,3-dipalmitin, 1-monopalmitin and soybean oil) in the presence of sodium chloride. The precursors were reacted with sodium chloride in an emulsion stabilised with an emulsifier under conditions which modelled the thermal treatment of foods during processing. The highest amount of bound 3-MCPD (released from its esters) was formed from 1-monopalmitin followed by 1,3-dipalmitin, whereas tripalmitin and soybean oil yielded the lowest levels of bound 3-MCPD. Four sets of experiments were then carried out aimed at monitoring the influence of various factors (soybean oil amount, NaCl content, water content, and temperature) on the yield of bound 3-MCPD. The formation of bound 3-MCPD was directly proportional to the concentration of either oil or NaCl. The highest amount of bound 3-MCPD was formed in media containing approximately 20% water. The amount of bound 3-MCPD decreased with increasing temperature over the range 100-230°C and reached its highest value at 100°C. Models with 1,2-dipalmitoyl-3-chloropropane-1,2-diol showed that the decomposition rate of this ester rapidly increased with increasing temperature over the range 100-230°C being the lowest at 100°C and the highest at 230°C.