采用超声提取、活性炭柱脱色和微孔膜过滤等步骤对蔬菜进行预处理，离子色谱法测定蔬菜中硝酸盐和亚硝酸盐含量。探讨不同贮藏条件下4种蔬菜中硝酸盐和亚硝酸盐含量的变化情况。结果表明：无论常温贮藏还是低温贮藏，贮藏7 d内，4种蔬菜中硝酸盐含量变化基本上是呈下降趋势，亚硝酸盐含量均呈现先急剧上升后近于平稳的趋势，但常温贮藏的亚硝酸盐含量高于低温贮藏，除韭菜外，其它蔬菜中亚硝酸盐含量均低于限量标准4 mg/kg。%Samples were pretreated by ultrasonic extraction, and de-colorizing through active carbon column, and filtering through microporous membrane. The determination of nitrate and nitrite in vegetables was carried out with ion chromatograph. The varieties of nitrate and nitrite content in 4 kinds of vegetables in different storage conditions were analyzed. The results showed that nitrate content decreased basically and that nitrite content was kept stable after increasing significantly in 4 kinds of vegetables kept in room or cooled temperature for 7 days , but nitrite content in vegetables stored at room temperature were higher than those at cold temperature. The nitrite contents in vegetables excluding garlic chive at both temperatures were below 4 mg/kg according to the limit standard of nitrite content in vegetables.
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