食品科学 ›› 2000, Vol. 21 ›› Issue (3): 51-53.

• 分析检测 • 上一篇    下一篇

食品中氮含量的差分脉冲极谱测定法

么淑珍,何莉萍   

  1. 天津医科大学卫生化学教研室天津
  • 出版日期:2000-03-15 发布日期:2011-11-29

Differential Pulse Polarographic Determination of Nitrogen in Food to Replace Kjedahl Nitrogen Determination

 ME  Shu-Zhen, HE  Li-Ping   

  • Online:2000-03-15 Published:2011-11-29

摘要: 研究了用差分脉冲极谱测定食品中氮含量的方法,将样品用凯氏烧瓶消化,消化液经稀释后定量吸取到甲醛醋酸盐缓冲溶液中,氨与甲醛反应生成六亚甲基四胺,电位在-0.9V处产生极谱波,以极谱波的峰高定量、本法重复测定的变异系数为46%~52%,回收率为94.5%~103.1%,对人奶和食品分析的结果与凯氏定氮法比较.没有显著性差异。

关键词: 差分脉冲极谱, 蛋白质, 氮, 食品

Abstract: A simple and rapid method was described for determining determining content by differentiall pulse polarography .The digest was diluted and pipetted into a solution of formaldehyde in an acetate buffer.The hexamethylentetramine,produced by ammonia and formaldehyde reaction was determined electrochemically at-0.9V .The coefficicient of variation was 4.6% to 5.2%,.The recovery rate of nitrogen was 94.5% to 103.1%.Human milk and eleven different food-stuffs were analysed.There was no significant difference between the results by this method and K jeldahl method.

Key words: Differential pulse polarography, Protein, Nitrogen, Food-stuff kjeldahl method