Abstract:The quality changes of fresh pork during refrigeration at 4 ℃were explored，and the deterioration process of processing quality was clarified by texture analysis，myofibrillar fragmentation analysis，and water retention analysis.Furthermore，the changes in oxidation characteristics of pork during this process were characterized by indicators such as thiobarbituric acid value（TBA），carbonyl value，and myoglobin composition.Principal component analysis（PCA）was used to elucidate the relationship between processing quality and oxidation characteristics of pork. The results showed that the quality of fresh pork continued to decrease with the extension of refrigeration time. After six days of refrigeration，the total volatile base nitrogen（TVB-N）content of pork reached 16.24 mg/100g，exceeding the national standard safety limit of 15 mg/100 g. The total number of colonies was 5.63 lg（CFU/g），approaching the corresponding limit，and the storage loss exceeded 10%. The oxidation characteristics of fresh pork also showed significant changes after six days of test. The TBA reached 0.22 mg MDA/kg，and the thiol value decreased to 87.28 nmol/mg.The carbonyl value increased to 2.04 nmol/mg protein. At the same time，the proportion of oxygenated myoglobin decreased，and the myoglobin fluorescence spectrum showed a red shift.The Schiff base content increased，and the tryptophan content decreased.PCA indicated that the 6th day of storage was a critical time point for pork storage.