High hydrogen peroxide concentration-low exposure time of plasma-activated water (PAW): A novel approach for shelf-life extension of Asian sea bass (Lates calcarifer) steak

A new method for using plasma-activated water (PAW; 100 ppm H2O2) to improve the cold (4 degrees C) shelf-stability of Asian sea bass steaks (ASBS) was established. Soaking with PAW, created utilizing oxygen and argon, for 30-120 s successfully extended the shelf-life of ASBS by suppressing microbial growths below the permissible level (7 log CFU/g) for 25 days, whereas control reached the microbiological limit after 10 days (p < 0.05). PAW-treated samples had lower accumulation rates of total volatile base nitrogen (< 25 mg/100 g), trimethylamine (< 5 mg/100 g), and propanal (< 400 nmol/g) than control (p < 0.05). PAW improved lipid stability (TBARS <2 mg/kg) but promoted protein oxidation (protein carbonyl similar to 0.01-0.02 nmol/mg). Hardness and water holding capacity of PAW treatments were better preserved during storage than control as indicated by higher breaking force and lesser expressible moisture drip. Although metmyoglobin tended to stay stable during storage, all treatments' surface total color change tended to increase by 2-5 folds. Overall, argon-produced PAW with 100 ppm H2O2 and a short soaking time (30 s) seemed to be a promising method for protecting the quality and safety of ASBS.