基于高光谱成像技术的三文鱼肉水分含量的可视化研究

Visualization of the Water Content for Salmon Fish Fillets Based on Hyperspectral Imaging Technique

提出了一种利用高光谱成像技术检测三文鱼水分含量并实现其可视化的新方法。采集不同水分含量的共100个鱼肉样本的高光谱图像,并提取样本感兴趣区域(ROI)的平均光谱。75个样本用于建模集,采用连续投影算法对原始光谱提取特征波长,利用提取的特征波长替代原始光谱,采用PLS建立预测模型,对25个预测集样本的水分含量进行预测,预测决定系数(R2)为0.904,预测均方根误差(RMSEP)为1.169%,获得了满意的预测精度。最后,用所建模型对预测集图像上每个像素点的水分含量进行预测,利用Matlab语言编程,三文鱼肉表面不同部位的水分分布采用不同颜色表示,进而实现三文鱼肉水分含量的可视化。结果表明,高光谱成像技术与化学计量学结合可以准确预测鱼肉的水分含量,与图像处理方法结合可以实现预测时间的可视化,能形象、直观地展示出鱼肉的水分含量分布情况,为实现水产品加工的自动化奠定了基础。

The potential of near-infrared hyperspectral imaging,as a rapid and nondestructive technique with the spectral wavelength range of 899~1 694 nm,was conducted to predict moisture content（MC）in Atlantic salmon fillets.Altogether 100 fish fillets cutting out from different parts of 5whole fillets were collected for hyperspectral image scanning.Mean spectral data were extracted automatically from the region of interest（ROI）of Atlantic salmon fillet surface.In order to reduce high dimensionality of hyperspectral images,successive projections algorithm（SPA）was performed to select optimal wavelengths for detection of MC in Atlantic salmon fillets.Partial least square（PLS）was carried out for the detection of MC in Atlantic salmon fillets based on spectral.The results showed that SPA-PLS achieved satisfactory result with R^2 of 0.913 and 0.904,RMSEP of 0.965% and1.169%for both calibration and prediction sets respectively.Then SPA-PLS models were built pixel-wise to the hyperspectral images of the prediction samples to produce chemical images for visualizing MC distribution.The results demonstrated that the potential of hyperspectral imaging technique to predict MC distribution in salmon fillets.