Effect of multiple freeze-thaw (F-T) cycles on the quality and protein oxidation of traditional Chinese sauce marinated beef

This study aimed to address the effect of repeated freeze-thaw (F-T) cycles on the quality of sauce marinated beef. The changes in nutritional components, edibles quality, lipid oxidation and protein oxidation of sauce marinated beef were evaluated under different F-T cycles. The results showed that with the increase of F-T cycles, the moisture, protein, crude fat content and shear force of sauce marinated beef decreased significantly (P < 0.05). The thiobarbituric acid (TBARS) value of sauce marinated beef increased, exceeding 1 mg/kg after 4 F-T cycles. Under 5 F-T cycles, the carbon-based content of sauce marinated beef sarcoplasmic protein and myofibrillar protein increased to 5.28 nmol/mg and 2.99 nmol/mg, respectively, while the sulfhydryl content decreased to 56.13 nmol/mg and 62.26 nmol/mg, respectively. In general, the nutritional composition and edible quality of sauce marinated beef, decreased with repeated F-T cycles. Considering the food quality and commercial value, the number of F-T cycles should be controlled as much as possible during transportation and sale. The results of this study provided a scientific reference for the quality change of sauce marinated beef products during frozen storage.