MCPD fatty acid esters in vegetable oils: formation, analysis and toxicology

3-monochoropropane-1, 2-diol (3-MCPD) and 2-monochloropropane-1,3-diol (2-MCPD) and glycidol esters (GE) have been known as food contaminants. These compounds are formed during high-temperature process of different food products such as coffee, edible oils, infant formula, potato based products, bakery products, malt, cooked meats, soy sauces and pickles. In vegetable oils, these compounds are formed during refining, particularly during deodorization step. The studies on MCPD content and their formation routes in vegetable oil are a new area of research. Carcinogenic characteristics of these ingredients are a general concern. Thermal processing such as deodorization and deep-frying can trigger the formation of unpleasant substance such as trans fatty acids cyclic fatty acid esters, or acylglycerol polymers. Refining of edible oils, although eliminates contaminants from the oil, but it leads to the formation of unwanted compounds such as glycidol, glycidol esters, MCPD and MCPD esters. This review gives valuable information of present knowledge on analytical aspect, formation mechanisms of 3-MCPD and GE in vegetable oils and their health implications such as toxicity, carcinogenicity and mutagenicity.