Effects of magnetic nanometer combined with radio frequency or microwave thawing on physicochemical properties of myofibrillary protein in sea bass
Wendi Zhang, Weiliang Guan, Luyun Cai, Xiaona Wang, Zhenzhe Zhang, Zan Ni
Abstract
This work was aimed to explore the effects of different thawing strategies on the properties of sea bass myofibrillar protein (MP) and organization structure. Results revealed that magnetic nanometer combined with radio frequency thawing (RT-Mag) and magnetic nanometer combined with microwave thawing (MT-Mag) increased the α-helical content and decreased β-sheet content, while RT-Mag had minimal effect on the secondary protein structure. Low-field nuclear magnetic resonance and SEM analysis revealed that RT-Mag and radio frequency thawing (RT) reduced the mobility and loss of immobilized and non-mobile water, had the most compact and ordered network structure. Decreases in the Tmax and enthalpies were observed in the thawing treatments expect for RT-Mag during the thawing process. The appearance of polymerized protein band of SDS-PAGE indicated that RT-Mag and MT-Mag occurred a mild oxidation. In addition, the changes of particle size indicated that MP pretreated by RT-Mag and MT-Mag had less aggregation and degradation. The UV second derivative showed that the effect of RT-Mag treatment was closer to that of FS, and the improvement effect of protein aggregation and oxidation was better. Therefore, RT-Mag of New thawing method can be used as an alternative method to improve MP performance and meat quality.