气相色谱法测定6大类食品中乙酰丙酸的含量

Determination of Levulinic Acid in 6 Kinds of Foods by Gas Chromatography

以六大类食品(饮料、糕点、面制品、酒、调味料、糖果)为研究对象,优化了现有国标测定乙酰丙酸的方法,对前处理方法进行优化,并且对检出限、回收率、精密度以及六大类食品样品、使用试剂、色谱柱、色谱条件进行了验证,证明方法的可行性及适用性。在VT-WAX柱(30 m×320 mm×0.25μm)分离,氢火焰离子化检测器(FID)测定,以保留时间定性,外标法定量。结果表明:乙酰丙酸在质量浓度在15～500μg·m L^(-1)范围内呈现良好的线性关系,相关系数R=0.998 7;加标质量浓度为60～240μg·m L^(-1),每个加标浓度平行三次(N=3)的平均回收率为86.0%～96.0%;检出限为5.5 mg·kg^(-1);相对标准偏差(RSD)为0.63%～3.3%。该方法前处理简便、结果准确、抗干扰性好且分析时间短,适用于饮料、糕点、面制品、酒、调味料、糖果等食品的常规分析和批量检测。

Six kinds of foods（beverage, pastry, flour, wine, seasoning, and candy） were studied. The existing methods for the determination of levulinic acid were optimized, and the pretreatment methods were optimized. The detection limit, recovery rate, precision and six kinds of food samples, using reagent, chromatographic column and chromatographic conditions were verified, which proved the feasibility and applicability of this method. It was separated by VT-WAX column（30 m×320 mm×0.25 μm） and determined by flame ionization detector（FID）. The retention time was used for qualitative analysis, and the external standard method was used for quantitative determination. The results showed that there was a good linear relationship between the concentration of levulinic acid and the concentration of 15-500 μg·mL^-1, the correlation coefficient was 0.998 7; The standard concentration was 60-240 μg·mL^-1. The average recovery（N=3） of levulinic acid was 86.0%-96.0%, the detection limit was 5.5 mg·kg^-1, and the relative standard deviation（RSD） was 0.63%-3.3%. This method was simple, accurate, anti-interference and short analysis time. It was suitable for the routine analysis and batch detection of beverage, pastry, flour, wine, seasoning, candy and other food.