Abstract:
This study investigated the effects of static magnetic field-assisted thawing on lamb quality using longissimus dorsi muscles as the experimental material. Following conventional freezing at −18 ℃ for 24 hours, samples were thawed at 4 ℃ in a magnetoelectric coupling thermostatic chamber under static magnetic fields of 0, 1, 2, 3, 4, 5, and 6 mT. A comprehensive analysis was performed to evaluate water-holding capacity, lipid oxidation, total volatile basic nitrogen (TVB-N), moisture distribution, and myofibrillar protein structure. The results demonstrated that compared with the 0 mT control, the 2 mT magnetic field treatment significantly reduced thawing time by 28.96% and markedly decreased thawing loss, centrifugation loss, and cooking loss by 55.32%, 20.71%, and 21.55%, respectively (
P<0.05). Analysis via low-field nuclear magnetic resonance and magnetic resonance imaging revealed that the 2 mT static magnetic field treatment effectively inhibited water migration during thawing, which maximized the retention of immobile water and enhanced water-holding capacity. Furthermore, this assisted thawing process significantly reduced thiobarbituric acid (TBARS) and TVB-N (
P<0.05), suggesting effective suppression of lipid oxidation and protein degradation. Finally, the treatment increased the total sulfhydryl content while reducing carbonyl content and surface hydrophobicity of myofibrillar proteins, demonstrating diminished protein oxidation and denaturation. Analysis of the secondary and tertiary structures further indicated that the 2 mT static magnetic field contributed to the stability of the protein structure. In summary, static magnetic field-assisted thawing effectively improved the water-holding capacity of lamb, inhibited lipid and protein oxidation, and stabilized the myofibrillar structure, thus enhancing the overall quality of the thawed product. This study provides a theoretical basis and technical support for the development of new thawing technologies for lamb meat.