Abstract: According to the first method for the determination of 1,2-propanediol in foods specified by the national food safety standard GB 5009.251-2016, 1,2-propanediol was extracted from milk powder using acetonitrile and was detected using a gas chromatograph (GC). Extraction solvent and standing time were investigated by one-factor-at-a-time method. Furthermore, response surface methodology (RSM) was employed to optimize oscillation time and standing time based on 1,2-propanediol recovery. The optimum extraction conditions were determined as acetonitrile, 4 ℃, 94–102 s and 1.2–1.4 h for extraction solvent, standing temperature, oscillation time and standing time, respectively. Under these conditions, the spiked recovery range of 1,2-propanediol was 95.2%–99.8%. The coefficient of variation for repeatability of the method was 1.62%, and it had good selectivity. The optimized method is suitable for the determination of 1,2-propanediol in milk powder.

Key words: infant formula; 1,2-propanediol; response surface methodology

摘要： 参考GB 5009.251—2016《食品安全国家标准 食品中1,2-丙二醇的测定》第一法建立乳粉中1,2-丙二醇的检测方法，采用乙腈在低温条件下提取乳粉中的1,2-丙二醇，并经气相色谱仪检测。通过单因素试验优选提取溶剂和静置时间，响应面试验研究振荡时间和静置时间与1,2-丙二醇回收率之间的关系。结果表明：确定优选方案为提取溶剂为乙腈，静置温度4 ℃，振荡时间94～102 s，静置时间1.2～1.4 h；优化后的方案可行，加标回收率为95.2%～99.8%，方法重复性的变异系数为1.62%，且有较好的选择性。优化后的方法可以满足乳粉中1,2-丙二醇的测定。

关键词: 婴幼儿配方乳粉；1,2-丙二醇；响应面试验