Extending Catfish Fillet Quality Through Active Packaging.

Chlorine Dioxide (ClO2) antimicrobial properties have been studied for many years. The application of ClO2 in seafood products, gelatin coating, and using the technology of a moisture-control package, bring a potential solution to overcome the main challenges related to their limited shelf-life by controlling moisture, avoiding lipid oxidation, and inhibiting microbial proliferation. The objective of this investigation was to evaluate the impact of gelatin treatment in conjunction with an antibacterial agent. (ClO2) packed in a moisture-control tray to extend the shelf-life of thawed catfish fillets. A preliminary study was conducted to determine the concentration of ClO2 before the final study. Fresh catfish fillets were separated into five groups: Control (CX), low concentration of ClO2 (LAX), high concentration of ClO2 (HAX), low concentration of ClO2 in a moisture control packaging (LAM), and high concentration of ClO2 in a moisture control packaging (HAM). A positive effect of ClO2 was observed in reducing microbial growth and reducing lipid oxidation compared to CX; however, no significant difference was found between higher and low concentrations of ClO2. For the final study, fresh catfish fillets were separated into four groups: Control (CX), gelatin coating (GX), ClO2 with gelatin coating (AGX), and ClO2 with gelatin in a moisture control packaging (AGM). All samples were frozen and stored in the freezer at ≤-20°C for 48 hours and then thawed overnight at ≤4°C for analysis. Physical/chemical and microbial activity were analyzed right after thawing and every four days for 20 days. Pseudomonas spp. and Psychrophilic bacteria counts showed no significant difference between groups through the study, presenting at day 0 a 3.08±0.40 and 3.95±0.29 Log CFU/g, respectively. All spoilage microorganism counts remained under the recommended threshold until day 8. For TBARS analysis, GX, AGX, and AGM (0.34±0.12, 0.33±0.10, 0.36±0.16 mg MDA/Kg) displayed significantly lower values compared to CX (1.20±0.33 mg MDA/Kg) throughout the study. All treatments for TBARS values remained under recommended limits. Utilizing gelatin and ClO2 does not help to extend the shelf-life of thawed catfish fillets regardless of the use of a regular or a moisture control tray. Gelatin coating prevents fat oxidation regardless of the packaging.