Abstract: In order to investigate the combined effects of ultrasound and slightly acidic electrolyzed water on the quality changes of vacuum-packaged sea bass (Lateolabrax japonicas) during refrigerated storage, fresh sea bass fillets were treated with ultrasonic (US) at 20 kHz and 600 W, slightly acidic electrolyzed water (SAEW), their combination (US + SAEW), or sterile water (as control) for 10 min and then stored in a refrigerator at 4 ℃. Total viable count (TVC), Psychrobacter count (PC), and physicochemical properties such as pH, total volatile base nitrogen (TVB-N) content, water migration, water-holding capacity (WHC)) and indicators lipid oxidation were measured every three days during storage. The results showed that the US and SAEW treatments inhibited the increase in TVC and PC during storage, and obviously slowed down the increase in pH and TVB-N content as compared to the control group. The US treatment greatly improved WHC. The SAEW treatment inhibited lipid oxidation in fish while improving WHC. Compared to the control group, the combined treatment provided the best quality preservation, and extended the shelf-life of refrigerated vacuum-packed sea bass by 6 days at least.

Key words: ultrasound; slightly acidic electrolyzed water; Lateolabrax japonicas; refrigerated storage; water migration; lipid oxidation