分光光度法测定固体蛋白饮料中蛋白质含量

Determination of protein in solid drink by spectrophotometry

中文关键词:  固体蛋白饮料  蛋白质  分光光度法

英文关键词:solid drink  protein  spectrophotometry

中文摘要:

      目的 建立分光光度法测定固体蛋白饮料中蛋白质含量的分析方法。方法 采用分光光度法测定固体蛋白饮料中蛋白质含量, 考察了该方法的线性、精密度及回收率, 并与凯氏定氮法测得的结果进行比较评价。结果 在氮含量为0~100 μg时, 分光光度法的标准曲线方程为C=229.6A400 nm?1.418, r2=0.998, 精密度实验相对标准偏差(relative standard deviation, RSD)为1.51%~2.53%, 重现性实验RSD为1.46%~2.80%, 5种饮料回收率分别为98.6%、99.2%、99.2%、98.3%、99.1%, 与凯氏定氮法测的结果进行比较, 无显著性差异。结论 该法具有简便快速、准确度高、精密度高、重现性好、检测效率高优势, 适合于固体蛋白饮料中蛋白质含量的测定。

英文摘要:

      Objective To establish a method for determination of the protein content in solid beverage by spectrophotometry. Methods The protein content in solid beverages was determined by spectrophotometry. The linearity, precision and recovery of the method were investigated and compared with the results measured by Kjeldahl method. Results When the nitrogen content was 0-100 μg, the standard curve equation of spectrophotometry was C=229.6A400 nm?1.418, r2=0.998, and the relative standard deviations (RSDs) of precision test and the current test were 1.51%-2.53% and 1.46%-2.80%, respectively. The recovery rates of the 5 beverages were 98.6%, 99.2%, 99.2%, 98.3%, and 99.1%, respectively. Compared with the results of the Kjeldahl method, there was no significant difference. Conclusion This method is simple, rapid, accurate, reproducible and high detection efficiency, which is suitable for the determination of protein content in solid beverages.