食品中蛋白质含量测定方法的探讨

目的:建立一种纳氏比色法测定食品中蛋白含量的检测方法。方法:样品经前处理后,在420nm波长处用纳氏比色法进行蛋白质含量测定。结果:本方法在氮含量为0.1～2.0mg/L范围内线性良好。样品蛋白质含量在2.80%～66.3%之间的相对标准偏差为0.96%～3.13%。该法与凯氏定氮法对不同样品进行蛋白质含量检测,无显著统计学差异。结论:该方法操作简便、快速、准确。

Study a method for determination of protein content in foods

Objective:To establish a method for determination of protein content in foods by Nessler′s Colorimetry.Methods:In the 420 nm wavelength The sample pretreatment were determined by Nessler′s Colorimetry.Results:The calibration curves were linear in the ranges of 0.1～2.0 mg/L for Nitrogen content. And The RSD was 0.96%～3.13% when Protein content in the samples were 2.80 % to 66.3%.There was no significant difference between samples of different protein content determined separately by this method and the Kjeldahlmethod.Conclusion:This method is simple,rapid and accurate.