高效液相法测定普洱茶焙烤制品中儿茶素及咖啡碱含量的研究

摘要

In order to accurately measure the retention rate of catechins and caffeine in Pu' er tea after baking, HPLC method was developed for the determination of catechins and caffeine in Pu' er bakery. The chromatographic conditions included reversed phase chromatographic column C18, the mobile phase of acetonitrile - water (containing 0.2% acetic acid), the flow rate of 1 mL/min, and the analytic wavelength of 270 nm. The result indicated that the effective components had a high reserved rate in the baking process. The reserved rate of catechins and caffeine was 90. 55% and 99.46% , respectively. At the same time, this method was simple, accurate, and good to separate. It could be used for determining catechins in baked food.%为准确测定普洱茶经焙烤后有效物质儿茶素及咖啡碱的保留率,建立了高效液相法,采用70％甲醇提取液提取茶焙烤制品中的儿茶素,并使用C18反相色谱柱,以乙酸乙腈-乙酸水为流动相进行梯度洗脱,流速为1mL/min;在波长为270 nm下经紫外分光法检测,结果表明:普洱茶粉的有效成分在焙烤过程中的保留率高,其中总儿茶素的平均保留率达90.55％,咖啡碱的平均保留率高达99.46％,因此该检测方法具有简便、准确、分离效果好的优点,适用于检测茶焙烤食品中儿茶素的含量.