水蒸气蒸馏-气相色谱法测定食品中丙酸及其盐类

Determination of propionic acid and Its salts in food by steam Distillation-Gas Chromatography

研究并优化了食品中丙酸及其盐类的水蒸气蒸馏-气相色谱检测方法。试样中的丙酸盐通过酸化转化为丙酸,经水蒸汽蒸馏收集后直接进气相色谱,用氢火焰离子化检测器检测。所用色谱柱为HP-FFAP(30.0m×250μm×0.25μm)毛细管柱,实验结果表明:一体化智能蒸馏仪效率高,重复性实验相对标准偏差为4.4%。本方法线性范围在0.02mg/mL～0.5mg/mL,相关系数r2=0. 9999,检出限为0.03g/kg,定量限为0.10g/kg,不同添加水平的添加回收实验回收率在83.3%～101.4%之间,相对标准偏差为1.5%～4.5%。改进后的方法回收率高,重复性好,杂质干扰少,线性良好,精密度高,能够满足日常检测要求。

The steam distillation-gas chromatography method for detecting propionic acid and its salts in food was studied. Propionate in the samples are converted to propionic acid by acidification,then went directly into gas phase chromatography after steam distillation;hydrogen flame ionization detector was used and the column was HP-FFAP(30.0 m × 250μm × 0.25μm)capillary. Experimental results show:The integrated intelligent distillation is highly efficient,and the relative standard deviation of the repeatability test is 4.4%. The method has a linear range from 0.02 mg/mL to 0.5 mg/mL,and a correlation coefficient r2 is 0. 9999,The detection limit is 0.03 g/kg,the limit of quantification is 0.10 g/kg. The recoveries for different amount of addition recovery experiments were from 83.3% to 101.4% with relative standard deviation from 1.5% to 4.5%. The improved method has high recovery rate,good repeatability,less impurity interference,good linearity and high precision. It can meet daily detection requirements.