牛肉嫩度的近红外光谱法检测技术研究

利用近红外光谱技术研究了牛肉嫩度的检测方法. 在波数为4 000～10 000 cm-1范围内测定牛肉样本近红外吸收光谱, 然后用沃-布剪切仪测得牛肉样本(背长肌)的最大剪切力值并进行主观嫩度等级评价. 把剪切力值小于6 kg的牛肉归为嫩牛肉, 等级值定为1;大于9 kg的牛肉归为老牛肉, 等级值定为3;介于6和9 kg之间的牛肉归为中等嫩度的牛肉, 等级值定为2. 研究结果表明, 老牛肉吸收的近红外光一般都要比嫩牛肉多, 表现为吸光度要大;用多元线性回归法对校正集建立模型, 得到相关系数r为0.806;用此模型对牛肉预测集19个样本进行预测, 分级正确率为84.21%. 该研究说明利用近红外技术对牛肉嫩度进行预测是可行的.

The Determination of Beef Tenderness Using Near-Infrared Spectroscopy

The prediction of beef tenderness was studied using near-infrared spectroscopy. The absorption spectra of beef samples were collected between 4 000 and 10 000 cm^-1 , the maximum shear force of these samples was obtained using the Warner- Bratzler attachment, and subjective judgment for the tenderness grade of beef was studied. Beef samples with the maximum shear force less than 6 kg were regarded as tender, and their tenderness grade was defined as the value of 1. Those with the maximum shear force greater than 9 kg were regarded as tough, and their tenderness grade was defined as the value of 3. And those with the maximum shear force between 6 and 9 kg were regarded as medium, and their tenderness grade was defined as the value of 2. The study shows that the absorption value of tougher beef is generally higher than that of tender beef. Multiple linear regression was used to build the model between the absorption value and tenderness grade. The results give the correlation coefficient r is 0. 806. The accuracy of the model for predicting tenderness grade of beef was 84. 21% for a validation set including 19 samples. This result indicates that NIR spectroscopy is capable of predicting tenderness grade of beef.