Fluctuated low temperature combined with high-humidity thawing to retain the physicochemical properties and structure of myofibrillar proteins from porcine longissimus dorsi

The physicochemical and structural changes in myofibrillar proteins (MPs) from porcine longissimus dorsi under low temperature combined with high-humidity thawing (4 °C, 90% RH, LHT) and fluctuated low temperature combined with high-humidity thawing (2 → 6 → 2 °C, 90% RH, FLHT) treatments were compared with those under refrigerator thawing (RT). The changes in the thermal stability and viscoelasticity of the MPs after FLHT treatment was insignificant (P < 0.05) compared with the corresponding properties of the fresh samples. In addition, FLHT resulted in a desirable water distribution, the highest total sulfhydryl content, and the lowest carbonyl content compared to the other treatments, suggesting that it effectively decreases protein oxidation. FLHT also led to slight changes in the aggregation and integrity of the MPs. Furthermore, a stable tertiary structure was obtained through FLHT. In contrast, the largest variations in all indicators of the MPs were observed following RT. These results confirmed that FLHT reduced the physicochemical deterioration of MPs from porcine muscle, thereby indicating the potential of FLHT for application in the thawing of meat.