Effects of ultra high pressure-magnetic field treatment on protein properties and quality characteristics of stored shrimp (Litopenaeus Vannamei)

The preservation of ultra high pressure (UHP) and magnetic field (MF) technologies on food have been reported, but the effect of combined treatment (UHP-MF) on aquatic product quality is rarely explored. The purposes of this study were to investigate the effects of UHP-MF treatment on protein properties and quality deterioration of stored Litopenaeus Vannamei. The vacuum-packed shrimps were treated at 200 and 300 MPa for 5 min, then stored in 5 mT MF for 12 days. Results showed the hardness, springiness, chewiness, shear force, L*, a*, b*, and W of muscle were improved by UHP, whereas the texture softening, a* and b* increase, water holding capacity were inhibited during MF storage. On the 12th day, compared with CON group, the cathepsin B, D, H, L activities, TBARS, carbonyl and dityrosine content in UHP300-MF group were reduced by 46.67%, 27.26%, 43.10%, 52.00%, 41.30%, 32.86%, and 30.42%, respectively. Furthermore, UHP-MF treatment slow down the accumulation of surface hydrophobicity, myofibril fragmentation index, and trichloroacetic acid-soluble peptide content. Generally, UHP-MF treatment inhibited lipid oxidation, weakened cathepsin activities, delayed protein oxidation and degradation of stored shrimp, retarded quality deterioration and prolonged shelf life of stored shrimp.