3-Monochloropropane-1,2-diol (3-MCPD) (free and esterified) in edible oil, soy sauce and infant formula: A systematic review of the occurrence and employed analytical approaches

3-Monochloropropane-1,2-diol (3-MCPD) is a food contaminant that has gathered special attention from food safety specialists and regulators. This article reviews reports on the occurrence of 3-MCPD (free form and/or esterified) in infant formula, soy sauce, and edible oils and discusses analytical procedures applied for its detection. Based on a literature search done in the databases PubMed and Scopus, 68 studies were included in the present systematic review. The highest concentration of 3-MCPD (free form and/or esterified) was found in soy sauce from China at 189 mg/kg of the product. Edible oil and soy sauce samples were found, in general, to contain relatively higher concentrations of 3-MCPD (free form and/or esterified) compared to infant formula. In the reviewed articles, a variety of analytical methodologies were employed, both for sample preparation/wet chemistry and for quantitative detection, with solid phase extraction and gas chromatography -mass spectrometry (GC -MS) being the most common approaches, respectively.