Molecular mechanism of exsanguination in enhancing the water-holding capacity of superchilled farmed golden pomfret

This study examined the effect of exsanguination on the water retention capacity of farmed golden pomfret under superchilled storage (−4 °C ± 1 °C). Additionally, it investigated the complex relationships among iron ion speciation, lipid and protein oxidation, and water retention. The moisture content significantly increased ( P < 0.05) as exsanguination time was extended. At the same time, centrifugal and cooking losses decreased markedly. Compared to the control group, the centrifugal and cooking losses in the 10 min exsanguination group had reduced by 10% and 8%, respectively. Exsanguination significantly reduced textural degradation and lowered oxidation levels of myofibrillar proteins and lipids. Before superchilled storage, heme and non-heme iron contents significantly decreased with prolonged exsanguination times. The heme iron contents in the group without exsanguination treatment were 12.4 mg/kg, and that in the 30 min exsanguination treatment group was reduced by 16%. After superchilling, the non-heme iron content in all treatment groups significantly increased. Exsanguination decreased non-heme iron content in muscle tissue, which could have contributed to lowered protein and lipid oxidation, ultimately improving the water-holding capacity of superchilled golden pomfret. This research helps delay quality deterioration in golden pomfret. • Exsanguination enhanced the water-holding capacity • Exsanguination treatment within 10 minutes can prevent the quality deterioration • Exsanguination decreased the heme iron and inhibited protein and lipid oxidation • The autooxidation rate of heme iron decreased with the prolonged exsanguination time