Pretreatment Methods for Determination of Caffeine in Coffee and Its Products by HPLC
Five pretreatment methods were used for five samples of coffee and its products respectively.The methods for extracting caffeine and HPLC determination of caffeine content of the samples were optimized and improved,and three new methods for caffeine determination were established.And they are accurate,rapid,safe and suitable for extracting caffeine from different samples.The results showed that the method of chloroform together with ultrasonic extraction was the best,and using this method to determine the caffeine content of FAPAS control sample showed that its caffeine content was 395.47 mg/kg,the relative error was 0.9%and the recovery rate was 100.97%.Meanwhile,the method had advantages of simple operation,less time consuming,high precision and accuracy,and it had features of wide application.