关键词: 氯丙醇酯；缩水甘油酯；婴幼儿配方奶粉；测定方法

Abstract: A novel gas chromatography-mass spectrometry (GC-MS) method was developed to determinate the contents of chloropropanol esters (MCPDE) and glycidyl esters (GE) in infant formula. The extraction conditions were optimized as follows: milk powder 1.50 g, ammonia solution 3.0 mL, drying temperature 105 ℃, and drying time 1 h. Under these conditions, satisfactory results were obtained. The limits of detection (LODs) were 5 and 10 μg/kg for MCPDE and GE (calculated as fat), respectively. A good linear range was obtained in the concentration range of 100–2 000 μg/kg with a correlation coefficient of 0.999. When a mixed standard was spiked to the fat extracted from infant formula YL-34 at levels of 100, 400, and 1 000 μg/kg, which were calculated on the basis of milk powder as 20.5, 82.0, and 205 μg/kg , respectively, the recoveries varied from 81.5% to 114% with relative standard derivations (RSDs) of 2.6%–10% (n = 6). When this method was applied in FAPAS international proficiency test, satisfactory results were obtained. Our results showed that the novel method had good accuracy and repeatability, and was suitable for quantification of both MCPDE and GE in infant formula. Therefore, the procedure has been included in the Chinese national food safety risk monitoring manual.

Key words: chloropropanol esters; glycidyl esters; infant formula; analytical method