几种茶叶中灰分含量研究

通过2种检测方法(程序控温法和525±25℃恒量法)对茶叶中总灰分、水溶性灰分、酸不溶性灰分和水溶性灰分碱度的研究表明,5种茶叶品种的水溶性灰分、酸不溶性灰分、水溶性灰分碱度均符合国家标准,但毛尖(宜昌)的总灰分含量达8.71%,超过了国家标准。2种检测方法测定的茶叶总灰分、酸不溶性灰分、水溶性灰分碱度的相对偏差基本在10%以内,在实际检测工作中不会带来方法误差;但测定茶叶水溶性灰分具有明显的方法误差。相对于525±25℃恒量法,在马弗炉中采取程序控温的方法测定茶叶灰分含量具有操作简便、人为误差少、省时、省事、精确等优点。

Investigation on the Contents of Ash in Some Teas

In order to research the contents of the ash in tea water,we dealt with five tea breeds by two measures（process temperature control method and constant 525 ± 25 ℃）.The result shows that the contents of the water-soluble ash,acid insoluble ash and alkalinity of water-soluble ash accord with national standard,but the content of total ash is percent 8.71 in Yichang maojian,and it is exceed of the standard.The relative deviation of contents of total ash,acid insoluble ash and alkalinity of water-soluble ash are under percent 10 by two measures,so it has not error of method in practice,but it has obvious error of method to measure the water-soluble ash.It has these advantages using process temperature control method,for example easy operation,less errors,saving time and effort,precision and so on.