The effects of trehalose synergy with NaCl on the textural, water distribution, and microstructure of snakehead fish filets induced by freeze–thaw cycles

In this study, we investigated the effect of trehalose in concert with NaCl on the flesh of snakehead fish that had undergone freeze-thaw cycles. Four groups of treatments were compared in this study, including distilled water, 3% NaCl, antifreeze (4% wt/vol) with 3% NaCl, and 4% trehalose (wt/vol) with 3% (wt/vol) NaCl. The results showed that the addition of 4% trehalose (wt/vol) with 3% (wt/vol) NaCl reduced the cracks between muscle fibers and the pores on muscle fiber bundles caused by freeze-thaw cycles during frozen storage of snakehead fish, thus reducing mechanical damage to the fish tissue structure. Moreover, the treatment was able to reduce the thawing loss of snakehead fillets, reduce cooking loss, and help maintain the color of the fish. Further, 4% trehalose (wt/vol) + 3% (wt/vol) NaCl (T) could slow down the reduction of hardness, elasticity, and chewiness of fish fillets during frozen storage. This study provides a theoretical basis for reducing the freeze-thaw cycle on the quality changes of snakehead fish during transportation and marketing.