茶叶中硒含量、浸出率及浸出液中硒的存在形式

The Selenium Content of Tea, Its Chemical Form and Amount Soaked out in Boiled Water

本文分析了正常地区、较高硒水平地区和慢性硒中毒地区的28份茶叶样品中硒的含量,并对其在水中溶解度、存在形式以及对硒摄入量的影响进行了研究。三个地区的茶叶样品中总硒含量分别为0.085±0.030,0.206±0.186和4.027±3.033ppm。茶叶中硒的浸出率分别为20.2％,20.8％和13.5％;范围分别为11.9～30.1％,14.2～24.4％和10.0～16.9％。浸出茶水中硒的存在形式,主要有无机Se^(6+),Se^(4+)和Se^(4+)以下硒,在正常地区分别占61.4±12.2％,13.8±7.7％和24.8±14.9％,较高硒水平地区分别占59.5±18.7％,11.3±9.0％和29.2±26.4％;慢性硒中毒地区分别为36.8±8.4％,9.5±3.5％和53.7±11.3％。与当地居民的其它食物的进食量相比,饮茶水对每日硒摄入量的影响甚微。如果把慢性硒中毒地区所产的茶叶转运到低硒地区,似有一定意义。

The selenium(Se)contents of tea samples from normal, higher and chronic selenosis areas were 0.085,0.206 and 4.027 ppm respectively. The average rates of selenium soaked out from samples of corresponding areas in boiled water were 20.2, 20.8 and 13.5％. The relative distributions of Se^(6+), Se^(4+) and below Se^(4+) in soaking water were observed to be 61.4, 13.8 and 24.8％ in samples from normal selenium area, 59.5, 11.3 and 29.2％ in samples from higher selenium area and 36.89 9.5 and 53.7 in samples from chronic selenosis area.Compared with the consumption of other foods, the influence of drinking tea on the daily selenium intake of local population is insignificant However, if the tea grown in chronic selenosis area is brought into low selenium area,it may be of certain significance for the improvement of selenium status of the local population.