Abstract:

Objective: To compare the sterilization effects of four kinds of processing agents on cobia fillets. Methods: The effects of food grade chitosan, solid chlorine dioxide (ClO2), ozone (O3) water and sodium hypochloride (NaClO) as the sterilization agents on cobia fillets were explored to screen the optimal sterilization agent and treatment conditions through the determination of total colonies, sensory evaluation and color difference. Results: The optimal sterilization conditions for individual application were 2 g/L chitosan for 8 min immersion, 200 mg/L ClO2 for 10 min treatment, 6 mg/L ozone water for 10 min sterilization and 100 mg/L sodium hypochloride treatment for 5 min. Through further comparing the effects of four sterilization agents on sensory quality of cobia fillets, chitosan, ClO2 and NaClO could result in a significantly negative effect on the sensory quality of cobia fillets; in contrast, ozone water treatment revealed an obvious sterilization effect without reducing the sensory quality of cobia fillets. Thus, ozone water was the best sterilization agent for cobia fillets. Conclusion: The optimal sterilization condition on cobia fillets is the treatment with 6 mg/L ozone water for 10 min. These investigations will provide a theoretical guidance for developing effective and safe sterilization agents for cobia fillet processing.

Key words: cobia fillet, sterilization agents, sterilization effect