25种市售蔬菜亚硝酸盐含量检测

Detection of nitrite content in 25 kinds of commercial vegetables

为检测目前市售常见蔬菜亚硝酸盐含量是否超过国家标准,本文采取重氮偶联比色法,测定了25种市售蔬菜的亚硝酸盐含量。结果显示,有12种蔬菜亚硝酸盐含量显著超过国家标准;有2种蔬菜达到了国家标准,但超标不显著;仅有11种蔬菜亚硝酸盐含量低于国家标准。其中绿叶类蔬菜亚硝酸盐含量超标最为严重,最高达国家标准的7倍;根茎类蔬菜亚硝酸盐超标稍轻,最高达国家标准的2.3倍;3种调味品类蔬菜中,只有生姜亚硝酸盐含量稍高。绝大部分瓜果类蔬菜亚硝酸盐含量较低,仅茄子亚硝酸盐含量超标。上述检测结果说明目前市售蔬菜亚硝酸盐污染严重,需采取有效的农业措施降低蔬菜亚硝酸盐含量。

In order to detect whether the nitrite content of commercial vegetables exceed the national standard at present,the nitrite content in 25 kinds of vegetables was determined by the diazotization-coupling colorimetry. The results showed that the nitrite content in 12 kinds of vegetables was significantly higher than the national standard; two kinds of vegetable were slightly higher than the national standard; only 11 kinds of vegetables met the national standards. Among them, the nitrite content in green leafy vegetables was highest, and the highest value was up to 7 times of the national standard. The nitrite content in root-shoot vegetables was lower than that in green leafy vegetables,and the highest value was about 2.3 times of the national standard. Only the nitrite content in ginger was slightly higher than the nation standard among the three kinds of seasoning vegetables. Most melon or fruit vegetables have lower level of nitrite, only the nitrite content in eggplant exceeded the national standard. These results indicated that the current commercial vegetables are seriously polluted by nitrite. Therefore, effective agricultural measures should be taken to reduce the nitrite content in vegetables.