摘要
分析研究了重庆市50余种蔬菜中硝酸盐含量状况及部分蔬菜中钾与硝酸盐含量的关系,结果表明:(1)约20种主要蔬菜中硝酸盐含量超过或远远超过联合国世界卫生组织和粮农组织1973年对食品中硝酸盐的限量标准;(2)不同品种蔬菜硝酸盐含量不同;(3)部分蔬菜中的钾与硝酸盐含量是极显著的负相关,其回旧模型为指数曲线方程。
The relations of potassium to nitrate contents in over 400 [samples of 50 vegetables marketed in chongqing City were analysed in this survey. Amongst these, about 20 fresh vegetables, such as celery, edible amaranth, curled mallow, Chinese cabbage, spinach, radish, swiss chard and mustard, contained 1500mg/kg of NaNO3 on average, and this is far exceeded the standard limit of nitrate in foods stipulated in 1973 by the w. H. O. and F. A. O. The contents of different varieties of a vegetable may vary considerably, e. g., fresh white stemed celery, green stemed celery, white swiss chard, green swiss chard, garlic stem and Spanish garlic stem contained 2860, 2600, 2100, 2000, 250 and 73mg/kg of NaNO3, respectively, 140 and 160 mg/kg nitrate were found in early and late mature varieties of kidney beans. There existed a close relationship between the contents of nitrate and potassium in different parts of some vegetables. The distribution of nitrate in various parts of celery, stem and root mustard, for example, followed the order old petiole> young petiole>old leaf>young leaf, but the distribution of potassium went the other way around. Regression analysis showed that the contents of potassium (X) and of nitrate (Y) were an exponential curve equation and negative correlation coefficient reached very significant level, and it may be shown in the following formula Y = 4709(0.0182)x,r = -0.9455 , n = 15. From the above function, a decline by an average of 33.0% nitrate may be expected when potassium content increases by 0.1% in a vegetable species.
出处
《西南农业学报》
CSCD
1992年第4期49-54,共6页
Southwest China Journal of Agricultural Sciences
基金
四川省科委应用基础项目
关键词
蔬菜
硝酸盐
钾
重庆
分析
Vegetables Nitrate content Potassium conlent Fertiltilizen Chongqin city
