Synergism effect of low voltage electrostatic field and antifreeze agents on enhancing the qualities of frozen beef steak: Perspectives on water migration and protein aggregation

In this study, a synergistic strategy utilizing low-voltage electrostatic field (LVEF) and antifreeze agents (4% sucrose +4% sorbitol) was proposed to reduce quality deterioration of prepared beef steak during freezing. The effects of the synergistic treatment on the water holding capacity, texture and muscle ultrastructure, myofibrillar protein (MP) aggregation was studied. Results showed that co-treatment significantly reduced thawing losses (about 41%) by preventing the migration of immobilized water to free water and reduced ice crystal size compared to air freezing (AF). In addition, co-treatment positively affected texture properties by shortening the gap between muscle fibers and maintaining the structural integrity of the sarcomeres. Moreover, synergistic treatment inhibited the unfolding of the MP structure and the formation of MP aggregates by strengthening non-covalent interactions. These results seem to demonstrate that LVEF can remarkably enhance the effects of cryoprotectants, which provides a new perspective on food cryoprotection. Freezing is the most common method of preserving prepared meat products, however, the formation of large ice crystals and the denaturation of muscle proteins are two major causes of quality deterioration during conventional air-freezing. In this study, a LVEF system was applied to the freezing process of prepared meat products, and a comparative and synergistic study was carried out with the current industry common chemical freezing protection methods (addition of antifreeze). The results showed that the synergistic treatment greatly promoted the nucleation of food products, shortened the phase transition time, reduced the ice crystal size and effectively reduced the thawing losses by approximately 41%. The green freezing system can be easily adapted to scenarios such as cold chain transport and cold storage. And the LVEF intensifies the interaction of antifreeze molecules with protein and water molecules, which seems to open up even more possibilities in cryopreservation.