Fluctuated Low Temperature Combined with High-Humidity Thawing to Reduce Physicochemical Quality Deterioration of Beef

The physicochemical quality of thawed beef inside cap off treated with fluctuated low temperature combined with high-humidity thawing (2 °C → 6 °C → 2 °C, RH 97 ± 3 %, FT) was compared with what was treated with refrigerator thawing (4 °C, RT). Results showed that compared with that of RT, the thawing loss, protein content of thawing drip, cooking loss, shear force, and carbonyl content of FT-treated beef decreased by 47.27, 42.15, 4.58, 12.02, and 30.0 %, respectively, while the sulfhydryl content increased by 24.63 %. Results of scan electron microscopy (SEM) and transmission electron microscopy (TEM) showed that FT-treated beef had smaller destructive effect on microstructures of muscle. Low-field nuclear magnetic resonance (NMR) relaxation measurements showed that FT and RT induced 2.46 and 6.10 % of immobile water shifting to free water, respectively, indicating the possible explanation of reduction of thawing loss with FT. It is demonstrated that FT can reduce thawing loss and physicochemical quality deterioration of beef, suggesting a bright application potential of FT on the thawing of frozen meat.