Nondestructive detection and visualization of protein oxidation degree of frozen-thawed pork using fluorescence hyperspectral imaging

This study evaluated the feasibility of non-destructive detection of carbonyl and total sulfhydryl contents by fluorescence hyperspectral imaging (F-HSI) to visualize the protein oxidation degree of pork during freezing -thawing process. Fluorescence hyperspectral image acquisition and chemical analysis were carried out on pork samples treated with different freeze-thaw cycles. Variational Mode Decomposition (VMD) was used to preprocess the raw spectrum, and Mutual Information-Variance Inflation Factor (MI-VIF) was applied to select the feature wavelengths. The Partial least squares regression (PLSR) models based on selected 19 wavelengths obtained good performance in predicting carbonyl content with R2p of 0.9275 and RMSEP of 0.0812 nmol/mg, and sulfhydryl content with R2p of 0.9512 and RMSEP of 1.2979 nmol/mg. The distribution maps of carbonyl and total sulfhydryl content were established based on the optimal prediction models. The results confirmed that the contents of carbonyl and total sulfhydryl in pork could be successfully predicted by F-HSI, so as to monitor the protein oxidation degree of pork during freezing-thawing.