偏最小二乘-光度法同时测定乳制品中含氮化合物

Simultaneous Determination of Nitrogen Compounds in Dairy Products by Partial Least Squares-Spectrophotometry

【目的】对重叠光谱的硝酸盐、亚硝酸盐和氨氮三组分体系的同时测定方法进行研究。【方法】按正交试验对不同浓度组成的硝酸盐、亚硝酸盐和氨氮模拟样品,在规定波长范围进行测定;建立偏最小二乘法测定三组分的校正模型,同时测定模拟混合样品和乳制品中三组分的含量。【结果】硝酸盐、亚硝酸盐和氨氮三组分模拟混合样品的回收率分别为100.1%、99.8%和104.1%;相对预报误差(RPEs)为1.94%、2.38%和6.78%;相对预报误差(RPEs)在允许范围内。【结论】该方法测量体系稳定,仪器简单,成本低,结果可靠,提供了一种新的测量途径。

[ Objective ] To study simultaneous determination of three - component system of nitrate, ni-trite and ammonia with overlapping spectra. [ Method] Measure simulative samples of monia with different concentrations in specified wavelength range through orthogonal partial least squares to determine calibration models of the three components; measure nitrate, nitrite and am- experiments; establish the content of the threecomponents in simulative mixed samples and dairy products. [ Result ] The recoveries of nitrate, nitrite and ammonia in simulative mixed samples were 100.1%, 99.8% and 104.1%, respectively; relative prediction errors （RPEs） were 1.94%, 2.38% and 6.78% ; relative prediction errors （RPEs） were within an allowable range. [ Conclusion ] With a stable measurement system, simple instrument, low cost and reliable results, a new measuring method has been provided.