Investigating the synergistic effects of acylglycerols on the selective formation of 3-MCPD and glycidyl esters in model soybean oil systems

The 3-monochloropropane-1, 2-diol esters (3-MCPDEs) and glycidyl esters (GEs), which are recognized as contaminants often produced during the deodorization process of refined edible oils, have garnered widespread attention and research interest in recent years due to their potential health risks to humans. Although there have been studies on the formation mechanisms of 3-MCPDEs and GEs, further clarification is still needed in the intrinsic synergistic effects of precursors. Herein, the synergistic effects of acylglycerols, including monoacylglycerols (MAGs), diacylglycerols (DAGs), and triacylglycerols (TAGs) on the formation of 3-MCPDEs and GEs were innovatively investigated through simulated deodorization experiments in model soybean oil systems. Additionally, the effects of simulated deodorization conditions, including temperatures, heating duration, chloride contents, and acylglycerol compositions on the production of 3-MCPDEs and GEs, were also investigated. The results indicated that under the simulated deodorization process and in the presence of chloride ions, the formation of 3-MCPDEs and GEs was facilitated by the synergistic interaction among MAGs, DAGs and TAGs. It is noteworthy that MAGs were more susceptible to forming 3-MCPDEs in the presence of chloride ions, whereas GEs predominantly resulted from the cyclization reaction of DAGs. Concurrently, when the MAGs content was less than 1%, or the presence of DAGs was less than 4% in the model system, the formation of both 3-MCPDEs and GEs was found to be below the EU regulatory limits, thus offering a solid theoretical basis for the control of 3-MCPDEs and GEs in refined oils.