Evaluating the effects of magnetic nanoparticles combined with ultrasound thawing on the physicochemical quality and myofibrillar protein properties in Antarctic krill (Euphausia superba).

This study aimed to investigate the effects of different thawing methods on the physicochemical quality and myofibrillar proteins (MPs) properties of Antarctic krill. To achieve this, the thawing rate, quality characteristics, water migration, and the structure and oxidative properties of the MPs were examined under three different thawing methods: hydrostatic thawing (HT), ultrasonic thawing (UT) and magnetic nanoparticles combined with ultrasound thawing (UMT). The results showed that UMT significantly shortened the thawing time as well as reduced thawing and cooking losses compared to HT and UT. Low-field nuclear magnetic resonance (LF-NMR) and Scanning Electron Microscopy (SEM) analysis revealed that UMT samples had lower free water (1.46 %), higher immobile water (92.86 %) and the most compact and ordered network structure. Results regarding solubility and turbidity indicated that the properties of MPs were notably enhanced following the UMT treatment. Meanwhile, UMT treatment reduced the oxidation and degradation of MPs, increased sulfhydryl content, and decreased carbonyl content. Besides, UMT showed stable protein secondary and tertiary structures. This study demonstrates that UMT can enhance the thawing characteristics of Antarctic krill and offers innovative thawing methods for use in the food industry.