近红外光谱技术快速无损测定干辣椒的辣度

Rapid nondestructive determination of pungency of dried peppers by near infrared reflectance spectroscopy (NIRS)

采用高效液相色谱测定干辣椒样品中的辣椒碱和二氢辣椒碱含量,利用透反射模式采集干辣椒样品的近红外光谱,采用偏最小二乘法(PLS)建立干辣椒样品的辣度评价的校正模型,并对模型用于预测。结果表明,筛选出建模光谱波段为9000～4000cm-1;通过残余方差(RVV)分析,确定了最适主成分数为8;干辣椒的辣度PLS评价模型的定标集和验证集的相关系数(RC,RV)分别为0.9871、0.9104,定标集和验证集的标准差(SEC,SEP)分别为2445、3976。研究发现,近红外光谱法作为一种快速而准确的定量分析手段,在干辣椒及其制品的辣度评价方面有广阔的应用前景。

Quantitative analysis of capsaicin and dihydrocapsaicin was carried out using a HPLC system. Meanwhile, the near-infrared spectra of all dried peppers samples were acquired in the trans-reflection mode. Calibration model for the relative values of pungency in dried peppers were established by partial least-squares regressions method. The results showed that the optimum waveband was 9000~4000 cm -1 . The eight principal components was selected by principal component analysis. The correlations of determination of calibration and validation sets （RC, RV） were 0.9871 and 0.9104, respectively. The standard deviation of calibration and validation set （SEC, SEP） were 2445 and 3976, respectively. As a rapid and accuracy measurement, the NIRS method showed a potential application in pungency evaluation of dried peppers and its products.