Determination of the total viable count of Chinese meat dishes by near‐infrared spectroscopy: A predictive model

Abstract

The total viable count (TVC) is an important index that reflects the freshness, contamination, and spoilage of dishes. Presently, near-infrared spectroscopy (NIR) is widely used for the assessment of TVC in raw meat, but there are few reports on the application of NIR spectroscopy to evaluate the TVC of Chinese meat dishes. Also, in the existing research, the modeling samples are industrial products, which makes it lack extensive representation, resulting in insufficient generalization ability of the model. Therefore, we prepared a relatively complex modeling sample to improve the application ability of the model. In this research, braised beef was investigated as an example to establish a predictive model of TVC in complex food matrices using NIR spectroscopy. For this purpose, five groups of 472 braised beef samples with different seasonings were used to collect NIR spectra (900–1,700 nm). For five groups, the periods of storage were tested using spectroscopy every day, after which the TVC was measured directly. Furthermore, we established a PLS prediction model. Later, the model established by using the best pre-processed spectral data for band selection, and the model established by band selection followed by variable processing methods were compared. The model using SPA band selection method followed by median center processing exhibited a good prediction ability, with the coefficient of correlation (R) of .8507, root mean squared error of prediction (RMSEP) of .2707 lg CFU/g, ratio of prediction to deviation (RPD) of 2.00, and ratio error range (RER) of 9.46. These results prove that the developed model can be used in the prediction of TVC in Chinese braised beef. Novelty impact statement Took Chinese braised beef as an example, this research has used NIR spectroscopy to predict the TVC in meat dishes that contained a range of seasonings and were stored for various periods. The model using the SPA band selection method followed by median center pre-processing exhibited a good prediction ability. The developed model can be used in the prediction of TVC in Chinese braised beef and to make a preliminary judgment on the edibility of Chinese dishes.