杜马斯燃烧定氮法和凯氏定氮法在蔬菜粗蛋白质含量检测中的比较  

Comparative Studies on Determination of Crude Protein in Common Vegetables by Dumas Combustion Method and Kjeldahl Method

作　　者：常硕 张延国[1] 刘广洋 许晓敏[1] 黄晓冬[1] 吕军[1] 徐东辉[1] CHANG Shuo;ZHANG Yanguo;LIU Guangyang;XU Xiaomin;HUANG Xiaodong;LYU Jun;XU Donghui(Institute of Vegetables and Flowers,Chinese Academy of Agricultural Sciences,Key Laboratory of Vegetables Quality and Safety Control,Ministry of Agriculture and Rural Affairs,Quality and Safety Risk Assessment Laboratory of Vegetable Products,Ministry of Agriculture and Rural Affairs,Beijing 100081,China)

机构地区：[1]中国农业科学院蔬菜花卉研究所,农业农村部蔬菜质量安全控制重点实验室,农业农村部蔬菜产品质量安全风险评估实验室(北京),北京100081

出　　处：《中国蔬菜》2021年第6期68-73,共6页China Vegetables

基　　金：国家重点研发计划项目(2018YFD0200803);国家自然科学基金项目(31872947);中国农业科学院科技创新工程协同任务项目(CAAS-XTCX2019024,CAAS-XTCX2019025);国家现代农业产业技术体系建设专项基金项目(CARS-23-E03)。

摘　　要：采用杜马斯燃烧定氮法(杜马斯法)和凯氏定氮法(凯氏法)对常见的15种蔬菜中粗蛋白质含量进行检测,并进行方法比较和数据分析。结果表明:杜马斯法相比凯氏法具有更加安全、环保、低能耗等优点;杜马斯法CV范围为0.3%~2.1%,回收率98.1%~101.9%;凯氏法CV范围为0.3%~1.4%,回收率98.7%~99.8%,均满足方法确认要求;方法检测结果呈显著的线性相关关系(R^(2)=0.9997),精密度范围在0.4%~8.1%,符合国标GB 5009.5-2016要求(RSD<10%);对绝大多数蔬菜来说,采用凯氏法和杜马斯法得到的粗蛋白质含量之间的差异并不显著,仅有硝酸盐含量高的大白菜、普通白菜和菠菜存在显著差异;进一步研究发现,蔬菜的高硝酸盐含量并不是导致两种检测方法检测结果差异显著的唯一原因,基质效应可能是另一重要原因,还有待研究确证。Dumas combustion ammonia determination method(Dumas method)and Kjeldahl nitrogen determination method(Kjeldahl method)were used to detect crude protein content in 15 common vegetables.And method comparison and data analysis were carried out.The results showed that compared with Kjeldahl method,Dumas method had the advantages of safety,environmental protection,low energy consumption,etc.The coefficient of variation CV of Dumas method was 0.3%-2.1%,and recovery rate was 98.1%-101.9%.The CV range of Kjeldahl method was 0.3%-1.4%,and recovery rate was 98.7%-99.8%.The precision and recovery rate of these 2 methods all meet the confirmation requirements.The results of method testing showed that a significant linear correlation(R^(2)=0.9997)with 0.4%-8.1%precision range was in line with the national standard GB 5009.5-2016(RSD<10%).For most vegetables,the difference between crude protein contents gained by these 2 methods were not significant.The significant differences only existed between Chinese cabbage,pakchoi and spinach with high nitrate content.Further studies found that high nitrate content in vegetables was not the only reason leading to the significant differences in test results by the 2 testing methods.The effect of vegetable substrate might be the another important reason,awaiting for further studies and confirmation.

关 键 词：杜马斯燃烧定氮法 凯氏定氮法 蔬菜 蛋白质 硝酸盐 

分 类 号：TS255.7[轻工技术与工程—农产品加工及贮藏工程]