Abstract: The method of high performance liquid chromatography with dual wavelength was established for simultaneous determination of caffeine and chlorogenic acid in coffee bean extracts. The result showed a good linear relationship between peak area and concentration in the range of 0.2—1.0 mg·mL-1. The regression equations of caffeine were: Y=44077X+227.78, R=0.9997, RSD=0.78%; the regression equations of chlorogenic acid were: Y=34896X+289.96, R=0.9995, RSD=0.93%. With chlorogenic acid content as indicator, the optimal conditions for extracting chlorogenic acid from green coffee beans were determined as follows: ethanol concentration was 20%, solid-liquid ratio was 6:1, extraction time was 60 min, the extraction temperature was 70 ℃ according to orthogonal test and single factor test. Taking caffeine and chlorogenic acid contents as indicators, the best decaffeination extractant was cyclohexane-trichloromethane-acetone mixture, and the extraction process was extracted three times with 1.5 volumes of cyclohexane-trichloromethane- acetone mixture with the caffeine content decreased from (3.52±0.08)% to (0.47±0.11)%.

Key words: coffee bean, chlorogenic acid, caffeine, extraction, process optimization

摘要： 建立高效液相色谱—双波长同时检测咖啡豆提取物中绿原酸和咖啡因含量的方法。咖啡因和绿原酸在0.2～1.0 mg·mL-1范围内，峰面积与浓度呈现良好的线性关系。咖啡因：Y＝44077X＋227.78，R＝0.9997，RSD＝0.78%；绿原酸：Y＝34896X＋289.96，R＝0.9995, RSD＝0.93%。以绿原酸含量为指标，在单因素试验基础上建立正交试验，确定从绿咖啡豆中提取绿原酸的最佳条件为乙醇浓度20%，液料比6∶1，提取时间60 min，提取温度70 ℃。以咖啡因和绿原酸含量为指标，通过萃取试验，确定最佳脱咖啡因萃取剂为环己烷-三氯甲烷-丙酮混合溶剂，萃取工艺为1.5倍体积萃取剂萃取3次，产物中咖啡因含量由(3.52±0.08)%下降至(0.47±0.11)%。

关键词: 绿咖啡豆, 绿原酸, 咖啡因, 提取, 工艺优化