鱼粉中氨基酸近红外光谱定量分析

收集了145个鱼粉样本,应用偏最小二乘（PLS）方法,建立了鱼粉中17种氨基酸和总氨基酸NIRS定标模型。天冬氨酸、蛋氨酸、赖氨酸、苏氨酸、谷氨酸、甘氨酸、丙氨酸、缬氨酸、异亮氨酸、亮氨酸、苯丙氨酸、精氨酸、脯氨酸和总氨基酸的化学分析值与NIRS预测值的决定系数R^2都达到0．87以上,相对标准差均小于10％,相对分析误差均大于3;酪氨酸的决定系数R^2为0．8678,相对标准差为8．65％,相对分析误差为2．77;组氨酸、丝氨酸和半胱氨酸的决定系数R。分别为0．9005、0．7436和0．3541,相对标准差分别为14．19％、17．85％和33．85％,相对分析误差分别为2．96、1．98和1．04。结果表明,利用近红外光谱分析技术能够较准确地检测鱼粉中14种氨基酸;酪氨酸只能进行粗略估测;组氨酸、丝氨酸和半胱氨酸难于进行实际检测。

Quantitative Analysis of Amino Acid in Fishmeal by Near Infrared Reflectance Spectroscopy

145 fishmeal samples were collected and the calibration models to predict total 17 types of amino acids and total amino acids in fishmeal,such as aspartic acid,methionine,lysine,threonine and so on,were developed by using partial least squares(PLS)technique.The coefficients of determination in calibration set(R2)of chemical analysis values and NIRS prediction values of aspartic acid,methionine,lysine,threonine,glutamic acid,glycine,alanine,valine,isoleucine,leucine,phenylalanine,arginine,proline and total amino acids were all over 0.87,the RSD all less than 10%,RPD all over 3;the R2 of tyrosine was 0.867 8,RSD 8.65%,RPD 2.77;the R2 for histidine,serine and cysteine were 0.900 5,0.743 6 and 0.354 1,respectively,RSD 14.19%,17.85% and 33.85%,respectively,RPD 2.96,1.98 and 1.04,respectively.The results show that NIRS analysis technique can be used to measure the contents of 14 kinds of amino acids,such as aspartic acid,methionine,lysine,threonine and total amino acid in fish meal accurately and to predict tyrosine content roughly.However,it can hardly be employed to measure histidine,serine and cysteine content in practice.