A nondestructive detection method of multi-quality parameters of beef by visible/near-infrared spectroscopy

摘要

The water content, color and pH value of beef play important roles in the evaluation of beef quality. The traditional determination methods of these parameters are destructive and time-consuming while a lot of literature show that visible and near-infrared spectrum have great potential in the determination of beef quality. In this paper, a method was developed to determine the water content, color and pH value of beef simultaneously. A detection probe with ring illuminator was built to improve the performance of the instrument. Sixty pieces of beef were collected from the supermarkets and famers markets of Beijing, while 75% of the samples were used as the calibration set of the model, the rest of the samples were used as the validation set. The reflectancespectra data of the samples werecollected by a dual channel visible and near infrared spectroscopic system in the range of 400nm to 2600nm, which the first section with a range of 400nm to 950nm and the second section with a range of 800nm to 2600nm. The diffuse reflectance spectrum of samples was performed with different pretreatments, such as standard normal variable transformation (SNV), detrend (DE) and multiplication scatter correction (MSC). Partial least squares regression (PLSR) models were establishedfor prediction of all these four parameters, respectively. Correlation coefficient (R) and root mean square error (RMSE) between prediction data and real data of the samples were used as evaluation criterions for the prediction model. Thespectral data of the first channel, the second channel and the full spectrum were conducted with the same pretreatment methods and modeling methods respectively. The results show that the utilization of the new detection probe achieved an effective improvement of the correlation coefficients and stability compared with the previous probes, and the PLSR models performed pretty well with better predicted correlation coefficient (R>0.85) and relatively small root mean square error. The present method builtby visible and near-infrared spectroscopy based on the new detection probe with ring illuminator can detect water content, color and pH value of beef nondestructively and rapidly.