食用油储存期品质变化的太赫兹光谱无损识别

Terahertz Spectroscopy for Non-destructive Identification of Quality Change of Edible Oils during Storage

为研究食用油在储存期间的品质变化情况,利用太赫兹衰减全反射技术对不同氧化程度的食用油进行无损识别。首先探究储存条件对食用油品质的影响情况,进一步根据国家定义食用油品质的标准将样品分为新鲜油、可食用油和不宜食用油,采集各类油品的太赫兹时域光谱,经数据预处理后采用欧氏距离匹配法进行聚类分析,并采用线性判别分析法进行样本分类,其中欧氏距离匹配法识别食用油折射率谱,准确率为95.65%;线性判别分析法识别吸收系数谱数据,准确率为91.00%,经比较两模型识别准确率理想,分析效果良好。该研究首先得出储存条件对食用油品质的影响规律,以论证太赫兹衰减全反射技术在分析食用油储存期品质变化方面的可行性,实现了食用油品质的快速无损检测;也可为太赫兹光谱技术深入应用于食用油多种属性的研究提供一定参考依据。

In order to evaluate the quality change of edible oils during storage,terahertz attenuated total reflection(THz-ATR)spectroscopy was used for the non-destructive identification of oils with different oxidation degrees.First,the effect of storage conditions on the quality of edible oils was explored,and then according to the national standard definition of edible oil quality,the collected samples were divided into fresh oil,edible oil and inedible oil.Terahertz time-domain spectra of these oils were collected.After data preprocessing,the euclidean distance matching method was used to identify the refractive index spectra of edible oils with an accuracy of 95.65%,and linear discriminant analysis(LDA)was used to identify the absorption coefficient spectra with an accuacy of 91.00%.Comparative analysis demonstrated that both models exhibited desired recognition accuracy.This study may provide a theoretical basis for the analysis of various quality attributes of edible oil by terahertz spectroscopy.