气相色谱法测定乳及其制品中肌醇含量的方法优化

目前,国标法-气相色谱法中测定食品中肌醇含量的方法存在操作步骤繁琐,操作稳定性不高,检测时间长的不足,为此,本文对《GB 5009.270—2016食品安全国家标准食品中肌醇的测定》中的气相色谱法进行了试样前处理、标品配制、色谱条件的优化。试验结果表明,本方法在0.02～0.12 mg范围内,呈良好的线性关系,相关系数R=0.9996,3个梯度的加标回收率分别为100.3%,97.8%,95.1%,加标回收率RSD为2.55%;样品重现性高,RSD为2.47%;优化后的色谱条件进样时间仅21.25 min。优化后方法较国标法简化了前处理中的干燥除水、测试液除水的步骤,减少了试剂用量,同时保证了检验的精密度、准确度不受影响。

Optimization of Determination of Inositol in Milk and Its Products by Gas Chromatography

At present,the national standard method-gas chromatography method for the determination of inositol content in food has the disadvantages of complicated operation steps,low operational stability and long detection time.This paper optimized the sample pretreatment,standard preparation and chromatographic conditions of gas chromatography in GB 5009.270—2016 national standard for food safety determination of inositol in food.The experimental results show that the method has a good linear relationship at the range of 0~0.12 mg,and the correlation Coefficient is 0.9996.Three gradients of spiked recovery were made.The spiked recovery rates were 100.3%,97.8%and 95.1%,respectively,and the spiked recovery rate RSD was 2.55%.High sample reproducibility,RSD was 2.47%.The optimized injection time was only 21.25 min.Compared with the national standard method,the optimized method simplifies the steps of drying and water removal,reduces the reagent dosage,simplifies the tedious pretreatment process.At the same time,it is ensured that the precision and accuracy of the inspection are not affected.