气相色谱法测定食醋中对羟基苯甲酸酯的方法优化

Optimization of determination of p-hydroxybenzoate in vinegar by gas chromatography

研究优化了气相色谱法测定食醋中对羟基苯甲酸酯(甲酯、乙酯、丙酯、丁酯)的检测方法。试样用盐酸酸化,无水乙醚提取,旋转蒸发浓缩后乙醇复溶,经HP-5毛细管柱分离,GC-FID检测,外标法定量。结果表明,4种对羟基苯甲酸酯能实现较好的分离分析,在4.0μg/m L~300μg/m L范围内线性良好,相关系数均大于0.999,方法检出限为0.24 mg/kg~0.40 mg/kg;在2.0 mg/kg~90 mg/kg添加水平下,回收率在81.2%~108.4%之间,RSD均小于5%,可以满足日常检测需求。

To optimize the determination method of p-hydroxybenzoate(methyl ester, ethyl ester, propyl ester, butyl ester) in vinegar by gas chromatography, the sample was acidified with hydrochloric acid, extracted with anhydrous ether, concentrated by rotary distillation, then re dissolved in ethanol, separated by HP-5 capillary column, detected by GC-FID and quantified by external standard method. The results showed that the four p-hydroxybenzoates could be separated and analyzed well, Between 4.0~300 μg/m L the linear range was good, the detection limit was 0.24~0.40 mg/kg, the recoveries ranged from 81.2~108.4% with RSD less than 5% at the addition level of 2.0~90 mg/kg, it could meet the needs of daily detection.