顶空气相色谱-质谱测定橄榄调和油中橄榄油含量

摘要

建立了测定橄榄调和油中橄榄油含量的顶空气相色谱-质谱分析方法.对样品量、加热温度、加热时间、进样量、进样模式、色谱柱进行了优化.通过化学计量学方法发现了橄榄油的特征化合物.取1.0 g样品放置于20 mL顶空瓶中,在180 ℃加热振摇2700 s,取1.0 mL顶空气体进样,通过HP-88色谱柱分离和质谱检测.结果表明,方法的线性范围为0~100%(橄榄油含量),线性相关系数(r2)大于0.995,检出限为1.26%~2.13%,模拟橄榄调和油中橄榄油含量测定的偏差为-0.65%~1.02%,相对偏差为-1.3%~6.8%,相对标准偏差为1.18%~4.26%(n=6).该方法不使用任何溶剂,操作简单、快速、环保,灵敏度和准确度高,适用于橄榄调和油中橄榄油含量的测定.%A method for the determination of the content of olive oil in olive blend oil by headspace gas chromatography-mass spectrometry (SH-GC/MS) was established.The amount of the sample,the heating temperature,the heating time,the amount of injection,the injection mode and the chromatographic column were optimized.The characteristic compounds of olive oil were found by chemometric method.A sample of 1.0 g was placed in a 20 mL headspace flask,and heated at 180 ℃ for 2700 s.Then,1.0 mL headspace gas was taken into the instrument.An HP-88 chromatographic column was used for the separation and the analysis was performed by GC/MS.The results showed that the linear range was 0-100%(olive oil content).The linear correlation coefficient (r2) was more than 0.995,and the limits of detection were 1.26%-2.13%.The deviations of olive oil contents in the olive blend oil were from-0.65% to 1.02%,with the relative deviations from-1.3% to 6.8% and the relative standard deviations from 1.18% to 4.26% (n=6).The method is simple,rapid,environment friendly,sensitive and accurate.It is suitable for the determination of the content of olive oil in olive blend oil.