Effects of Different Pretreatment on Curcumin-mediated Photodynamic Inactivation and Preservation of Large Yellow Croaker (Larimichthys crocea)

In order to investigate the effect of different pretreatment methods on the preservation efficacy of curcumin-mediated photodynamic inactivation (PDI) for aquatic products, four pretreatment methods were evaluated for their PDI preservation effect on Larimichthys crocea, including incubation after spraying curcumin solution, no incubation after spraying, incubation after soaking, and no incubation after soaking. The results demonstrated that PDI treatment was performed on L. crocea after soaking in the curcumin aqueous solution of 10 mmol/L and incubating for 30 min, resulted in higher sensory acceptability compared to the other three pretreatment methods after 8 days of refrigeration at 4 ℃. Additionally, this treatment effectively preserved the color of refrigerated L. crocea. Meanwhile, the total viable count (TVC), pH, and total volatile basic nitrogen (TVB-N) content of L. crocea under this treatment were the smallest, which were 5.82±0.07 lg CFU/g, 7.07±0.02, and 17.45±0.35 mg/100 g, respectively. This pretreatment method could effectively inhibit the increase of TVC, pH and TVB-N content, thereby preserving the quality of refrigerated L. crocea and extending the shelf life. Therefore, the pretreatment method of immersion followed by incubation in curcumin aqueous solution was an essential prerequisite for obtaining efficient PDI preservation of aquatic products mediated by curcumin.