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ObjectiveAn online fully automated alkaline hydrolysis method for the determination of chloropropanol esters （MCPDE） and glycidyl esters （GE） in edible oils and fats was developed， and the effects of vegetable oil type and temperature on the conversion of GE to 3-chloro-1，2-propanediol （3-MCPD） were investigated.MethodsBased on the basic principles of AOCS Cd 29c-13， the samples were subjected to hydrolysis， chlorination， liquid-liquid extraction and derivatization on a fully automated sample pretreatment platform， and then separated by a DB-5MS column after injection. The data was determined by multiple reaction monitoring mode （MRM） coupled with the internal standard method.ResultsThe efficiency of GE conversion to 3-MCPDE in the five vegetable oils was significant different. However， the effect of temperature was relatively greater. The alkali hydrolysis time was optimized， and the hydrolysis of MCPDE and GE was basically completed when the hydrolysis was carried out for 7 min at 10℃. The limits of detection for 2-chloro-1，3-propanediol （2-MCPDE）， 3-chloro-1，2-propanediol （3-MCPDE） and GE were all 5 μg/kg calculated by their free forms. There was a good linear relationship between the concentration and ratio of the response ranged from 0 to 0.4 μg/mL. When spiked from 20 to 2 500 μg/kg， the recoveries of MCPDE and GE ranged from 90.3% to 109.7% with the relative standard deviation （n=6） of 1.3%-7.7%， indicating that the precision was better than that of the manual procedure. The method was comparable with the Chinese national standard method for food safety under reviewed and was successfully applied to the determination of FAPAS proficiency test samples.ConclusionThe novel automatic procedure has the advantages of simple operation and high sensitivity， which reduces the labor intensity， improves the detection efficiency and repeatability compared with the reported manual procedure， and can better meet the requirement for quantification of MCPDE and GE in edible oils and fats.