Cryoprotective effect of trehalose on myofibrillar protein of snakehead fish (Channa argus) during freeze-thaw cycles

This study investigated the cryoprotective effect of trehalose on myofibrillar protein (MP) of snakehead fish (Channa argus) during freeze-thaw (F-T) cycles. After 7 F-T cycles, trehalose reduced solubility loss by 9.8 % compared to control group. Turbidity and surface hydrophobicity increased significantly with repeated F-T cycles. However, trehalose, particularly at 1.5 %, effectively inhibited these changes by stabilizing the structure and reducing aggregation. Sulfhydryl content decreased by 10.8 % less in the trehalose group than in the control group, indicating reduced oxidative damage and maintaining sulfhydryl groups. Differential scanning calorimetry (DSC) and scanning electron microscope (SEM) showed that trehalose reduced freezable water content and minimized structural damage caused by ice crystals, with 1.5 % trehalose exhibiting the most pronounced effect. Trehalose's polyhydroxylated structure forms hydrogen bonds with polar residues, reducing hydrophobic interactions and maintaining protein stability. Additionally, trehalose reduced secondary structure degradation, offering optimal protection against oxidation, aggregation, and structural damage during F-T cycles.