The formation of 2- and 3-monochloropropane-1,2-diol (2- and 3-MCPD) esters and glycidyl esters (GE) during high-temperature edible oil refining is a well-documented concern. These contaminants pose significant health risks, as free MCPD and glycidol are classified as potential human carcinogens.
To mitigate these risks, European Union Regulation (EU) 2023/915 establishes maximum allowable levels for these contaminants in foodstuffs. For most vegetable oils (e.g., coconut, maize, rapeseed, sunflower, soybean, olive), the permissible limit for 3-MCPD esters is 1,250 μg/kg. In contrast, oils from palm kernel are subject to a higher limit of 2,500 μg/kg. The limit for glycidyl esters (expressed as glycidol) is 1,000 μg/kg across all oils and fats.
This application note details the simultaneous analysis of 2-, 3-MCPD and glycidyl esters in accordance with the above regulatory requirements. The AOCS Official Method Cd 29c-13 was
used due to its significant advantages for high-throughput labs. Unlike the lengthy hydrolysis (often 16 hours) of methods Cd 29a or 29b, this method uses a rapid alkaline transesterification, offering faster, more efficient sample preparation, particularly when integrated with automated workflows. This work
demonstrates the complete, automated procedure using the Gerstel Multi-Purpose Sampler Workstation and a Shimadzu GCMS-QP2020 NX system, a combination that enhances analytical
precision, minimizes human error, and improves laboratory productivity.
