顶空固相微萃取-气相色谱法检测啤酒中辛酸和癸酸

Determination of Caprylic Acid and Capric Acid in Beer by Head-space Solid Phase Microextraction

利用SAS软件的Plackett-Burman试验设计法及响应面分析法,对顶空固相微萃取-气相色谱法检测啤酒中辛酸和癸酸的萃取条件进行优化,较佳的萃取工艺条件为:萃取温度51.32℃,萃取时间42.23min,加盐量0.51g/ml。方法的重复性较好、回收率较高,峰面积相对标准偏差(RSD)小于4%,辛酸和癸酸检测限分别为0.404μg/L和0.046μg/L,在0.404～8080mg/L和0.046～920mg/L浓度范围内线性关系良好,相关系数在0.999以上。

The Head-space solid phase microextraction conditions for analysis octanoic acid and capric acid in beer were optimized by SAS software combined with Plackett-Burman design and the response surface analysis. The optimal conditions were as follows： extract temperature 51.32℃, extract time 42.23 min and salt dosage 0.51 g/ml. This method had a better duplication and a higher recovery. The relative standard deviations （RSD） of peak areas for fatty acids were less than 4%, the detection limits of octanoic acid and capric acid was 4.04 μg/L and 0.046μg/L, respectively, and the working curve linear scope was 0.404-8080 mg/L and 0.046-920 mg/L, respectively, with correlation coefficient more than 0.999.