Zhu Rong-guang, Yao Xue-dong, Duan Hong-wei, Ma Ben-xue, Tang Ming-xiang
Guang Pu Xue Yu Guang Pu Fen Xi. 2016 Mar;36(3):806-10.
Total Volatile Basic Nitrogen (TVB-N) was usually taken as the physicochemical reference value to evaluate the mutton freshness. In order to explore the feasibility of hyperspectral (HSI) imaging technique to detect mutton freshness, 71 representative mutton samples were collected and scanned using a diffuse reflectance hyperspectral imaging (HSI) system in the Visible-Near infrared (NIR) spectral region (400-1 000 nm), and the chemical values of TVB-N content were determined using the semimicro Kjeldahl method according to the modified Chinese national standard. The representative spectra of mutton samples were extracted and obtained after selection of the region of interests (ROIs). The samples of calibration set and prediction set were divided at the ratio of 3 : 1 according to the content gradient method. Optimum HSI calibration models of the mutton (TVB-N) were established and evaluated by comparing different spectral preprocessing methods and modeling methods, which included Stepwise Multiple Linear Regression (SMLR), Partial Least Squares Regression (PLSR) and Principal Component Regression (PCR) methods. The results are that through the utilization of Multiplicative Scatter Correction (MSC), first derivative, Savitzky-Golay (S-G) smoothing and mean-centering together, both PLSR and PCR were able to achieve quantitative detection of mutton TVB-N. As for the PLSR model of mutton TVB-N established, the spectral pretreatment methods chosen included MSC, first derivative, S-G (15,2) smoothing and mean-centering, and the latent variables (LVs) number used was 11. As for the calibration set of PLSR model of mutton TVB-N, the correlation coefficient (r) and root mean square error of calibration (RMSEC) were 0.92 and 3.00 mg x (100 g)(-1), respectively. As for the prediction set of PLSR model of mutton TVB-N, the correlation coefficient (r), Root Mean Square Error of Prediction (RMSEP), and ratio of standard deviation to standard error of prediction (RPD) were 0.92, 3.46 mg x (100 g)(-1) and 2.35, respectively. The study demonstrated that the rapid and accurate analysis of TVB-N, the key freshness attribute, could be implemented by using the hyperspectral imaging (HSI) technique. The study provides the basis for further rapid and non-destructive detection of other mutton freshness attributes by using the hyperspectral imaging (HSI) technique, the improvement of current modeling effect of TVB-N content and the application involved of the technique in the practical production.
总挥发性盐基氮(TVB-N)通常被用作评估羊肉新鲜度的理化参考值。为了探究高光谱(HSI)成像技术检测羊肉新鲜度的可行性,采集了71个具有代表性的羊肉样本,并使用可见-近红外(NIR)光谱区域(400-1000nm)的漫反射高光谱成像(HSI)系统进行扫描,同时根据修改后的中国国家标准,采用半微量凯氏定氮法测定TVB-N含量的化学值。在选择感兴趣区域(ROIs)后,提取并获得了羊肉样本的代表性光谱。根据含量梯度法,以3:1的比例划分校准集和预测集样本。通过比较不同的光谱预处理方法和建模方法,包括逐步多元线性回归(SMLR)、偏最小二乘回归(PLSR)和主成分回归(PCR)方法,建立并评估了羊肉(TVB-N)的最佳HSI校准模型。结果表明,通过同时使用多元散射校正(MSC)、一阶导数、Savitzky-Golay(S-G)平滑和均值中心化,PLSR和PCR都能够实现对羊肉TVB-N的定量检测。对于所建立的羊肉TVB-N的PLSR模型,选择的光谱预处理方法包括MSC、一阶导数、S-G(15,2)平滑和均值中心化,所使用的潜在变量(LVs)数量为11。对于羊肉TVB-N的PLSR模型校准集,相关系数(r)和校准均方根误差(RMSEC)分别为0.92和3.00mg x(100g)(-1)。对于羊肉TVB-N的PLSR模型预测集,相关系数(r)、预测均方根误差(RMSEP)和预测标准差与标准误差之比(RPD)分别为0.92、3.46mg x(100g)(-1)和2.35。该研究表明,利用高光谱成像(HSI)技术可以实现对关键新鲜度属性TVB-N的快速准确分析。该研究为进一步利用高光谱成像(HSI)技术快速无损检测其他羊肉新鲜度属性、改善当前TVB-N含量的建模效果以及该技术在实际生产中的应用提供了依据。