Acidified Sodium Chlorite Solution as an Antimicrobial Treatment for Rainbow Trout (Oncorhynchus mykiss) Fillets

Abstract

Minimizing microbial growth and maintaining overall quality are priorities for intervention strategies that extend the shelf life of fresh, aquatic foods. Four treatments included a control (fresh fillets), water, 50 ppm of acidified sodium chlorite (ASC), and 1,000 ppm of ASC. Fillets were stored at 1 to 2°C for 0, 8, and 15 days. A significant (P < 0.05) interaction between treatment and storage time was observed for psychrotrophic counts. The increase in psychrotrophic counts with storage time was less for fillets treated with ASC, regardless of ASC concentration. Aerobic plate counts were not affected (P > 0.05) by intervention; however, a significant increase in counts was observed during storage (P < 0.05). Fillet pH, moisture, fat, thiobarbituric acid–reactive substances, fatty acid composition, color, cook yield, and shear force were not affected (P > 0.05) by intervention. Thiobarbituric acid–reactive substances decreased (P < 0.05) during storage. Percentages of individual fatty acids were constant, with the exception of C15 and C20:2; they decreased with storage to 15 days. Percent fat, L* (lightness) and b* (yellowness) values, and cook yield increased (P < 0.05) during storage. Fillet pH, moisture, a* (redness) value, and shear force did not change (P > 0.05) with storage to 15 days. Based on these data, 50 ppm of ASC performed equally as well as 1,000 ppm of ASC. The value of ASC is as a decontaminant; however, fillets in this study had low psychrotrophic counts pretreatment (2.3 log CFU/cm2) and posttreatment (2.03 log CFU/cm2), which did not demonstrate ASC's effectiveness as a decontaminant.