京郊主要蔬菜产品器官硝酸盐与亚硝酸盐含量分析与评价

对京郊52种蔬菜产品，以及同一种类不同品种、同一品种产品的不同部位的硝酸盐、亚硝酸盐和VC含量等进行测定。结果表明：供试蔬菜产品器官的硝酸盐含量在不同种类、品种及其不同部位间存在明显差异。以蔬菜鲜质量器官中硝酸盐含量均值计算，根菜类(420.66mg/kg)＞叶菜类(281.24mg/kg)＞茎菜类(279.54mg/kg)＞果菜类(176.54mg/kg)＞花菜类(157.93mg/kg)；同种蔬菜品种间的硝酸盐含量相差1.13～5.48倍；产品器官不同部位的硝酸盐含量也有较大差异，如结球叶菜硝酸盐含量外叶＞中叶＞内叶，叶柄＞叶片，黄瓜果实顶部、基部＞中部，果肉＞果心，萝卜根皮＞根肉。各供试蔬菜产品器官的亚硝酸盐含量多在1mg/kg以下，个别蔬菜种类如茼蒿可达6.74mg/kg，不同蔬菜种类、品种和部位间亚硝酸盐含量差异不如硝酸盐含量差异明显。果菜类、叶菜类和花菜类蔬菜产品器官的VC含量普遍较高，如辣椒可达146.56mg/100g，但品种间VC含量差异不显著。由此可见，目前京郊蔬菜产品器官中的硝酸盐和亚硝酸盐含量多在安全范围内，但仍建议消费者科学合理进行蔬菜种类搭配以保障人体健康。

Analysis and Evaluation on Nitrate and Nitrite Contents in Vegetables from Beijing Suburb

Recent years,nitrate content in vegetables has gained extensive attention. The contents of nitrate,nitrite and vitamin C in 52 kinds of vegetables from Beijing suburb were determined. Results indicated that a difference in nitrate accumulation was observed among different species,cultivars and parts of some vegetables. The contents of nitrate in different vegetable species calculated on the basis of fresh weight declined in the following order:root vegetables (420.66 mg/kg),leafy vegetables (281.24 mg/kg),s...