气相色谱法测定面包中三种单甘油酯含量

摘要

建立了气相色谱法检测面包中3种单甘油酯(单辛酸甘油酯、单癸酸甘油酯和单月桂酸甘油脂)含量的分析方法.样品以二氯甲烷-正己烷(1∶1)提取,提取液经浓缩后,用正己烷饱和乙腈萃取,气相色谱测定,外标法定量.3种单甘油酯在20～1 000 mg/L范围内呈良好线性,相关系数(r)大于0.999.3种单甘油酯的定量下限分别为35.2、23.3、12.8 mg/kg,加标回收率为81.1％～95.7％,相对标准偏差(RSD)为2.9％～8.8％.该法操作简便、灵敏度高、重现性和选择性好,可用于面包中3种单甘油酯的检测.%A gas chromatographic (GC) method was established for the determination of three kinds of mono-glycerates(e.g.glycerate monocaprylin,glyceryl monodecanoate and glycery monolaurate) in bread.The sample was extracted with dichloromethane-n-hexane (1 ∶ 1).The extract was concentrated,then extracted with acetonitrile saturated with n-hexane,and detected by GC with the external standard method.The calibration curves for three mono-glycerates were linear in the range of 20-1 000 mg/L with correlation coefficients more than 0.999.The limits of quantitation of 3 monoglycerides are 12.8-35.2 mg/kg.The spiked recoveries were in the range of 81.1％-95.7％ with RSDs of 2.9％-8.8％.The method has the advantages of simple operation,high sensitivity,good reproducibility and selectivity,and could meet the requirements for trace analysis of three monoglyceride in bread.