Research on the Determination Method of Total Nitrogen Content in Plant Samples
In order to determine the total nitrogen content in plant and food samples more efficiently and safely,with referring to the method of GB 5009.5-2016 National food safety standard Determination of protein in food,the full-automatic Kjeldahl nitrogen meter method was used to optimize the conditions such as symmetrical sample quantity,reagent dosage and digestion temperature.The standard error between the nitrogen content of plant reference material determined by the improved method and the fixed value of nitrogen content of reference material is 0.67%~6.45%,the RSD value of the determination result is 0.51%~3.71%,and the recovery of standard addition is 95.2%~104.1%.The improved method reduces the experimental cost,reduces the impact of waste emissions on the environment,and improves the digestion efficiency and the safety of experimental personnel.The precision and accuracy meet the requirements of detection and analysis,and are suitable for the detection of total nitrogen content of batch plant samples.