采用气相色谱法测定食品中12种有机酸的含量。采用硫酸-甲醇溶液对食品中12种有机酸进行衍生，优化的试验条件如下：①硫酸-甲醇溶液（衍生试剂）的体积分数为20%；②衍生温度为80℃；③衍生试剂的加入量为4.0 mL；④衍生时间为60 min；⑤萃取试剂为三氯甲烷。用Agilent HP-5毛细管色谱柱（30 m×0.32 mm，0.25 μm）分离，氢火焰离子化检测器检测。12种有机酸的质量浓度均在一定范围内与其衍生产物的峰面积呈线性关系，方法的检出限（3S/N）为0.023~0.076 mg·kg^-1。方法用于食品样品的分析，加标回收率为76.0%~107%，测定值的相对标准偏差（n=6）为1.5%~6.9%。

GC was applied to the determination of 12 organic acids in foods. 12 organic acids in foods were derived with H₂SO₄-CH₃OH solution. The optimized conditions found were as follows:① volume fraction of H₂SO₄-CH₃OH solution (derivative reagent) was 20%; ② derivative temperature was 80℃; ③ adding amount of derivative reagent was 4.0 mL; ④ derivative time was 60 min; ⑤ extraction reagent was CHCl₃. The analytes were separated on Agilent HP-5 capillary column (30 m×0.32 mm, 0.25 μm) and detected by FID. Linear relationships between values of peak area of the derivative product and mass concentration of the 12 organic acids were kept in definite ranges. Detection limits (3S/N) found were ranged from 0.023 to 0.076 mg·kg^-1. The proposed method was applied to the analysis of foods samples, giving values of recovery and RSD's (n=6) in the ranges of 76.0%-107% and 1.5%-6.9% respectively.