Submitted to: Aquaculture America Conference
Publication Type: Abstract Only
Publication Acceptance Date: 10/30/2017
Publication Date: N/A
Technical Abstract: Frozen storage is one of the major ways to maintain product quality and safety for an extended period of time. Frozen products can include preheated or precooked seafood products that will be reheated often in a microwave prior to being served. Product quality slowly deteriorates with time during frozen storage and shelf-life of many product is less than 8 months depending on temperature, packaging and number of other factors. There is limited knowledge on the quality of precooked fish fillets during frozen storage. The objective of this study was to examine changes in quality of precooked catfish fillets during frozen storage for up to 10 months. The effect of two packaging materials on storage stability was also evaluated. Catfish IQF (Individually Quick Frozen) fillets treated with polyphosphate were purchased from a commercial Mississippi catfish processor, trimmed and cut vertically into three pieces, with each weighing approximately 50 g. The catfish fillet pieces were precooked in a 121°C convection oven to an internal temperature of 60°C. Half of the precooked fillet pieces were individually vacuum-packaged in poly-nylon vacuum pouches, and half were placed in Ziploc bags. Samples were then stored in a -20°C freezer and samples analyzed after 0, 1, 6, 10 month(s) of frozen storage. Four randomly selected fillet pieces were analyzed for each treatment and measurements included drip loss, proximate content (% protein, % lipid, % ash and % water), color (CIE L*a*b*), pH, mechanical texture, and lipid peroxidation (TBARS). Data were statistically analyzed. Within treatments, storage time showed no or minor effect on proximate content. The vacuum-packaged samples had lower (~1%) moisture contents and greater drip losses than the comparable sandwich bag packaged samples. Frozen fillet pieces were similar in terms of malonaldehyde (MDA) concentration between treatments for up to 10 months of frozen storage. Fillet texture properties of vacuum-packaged samples remained consistent during the 10-months of frozen storage; however, the sandwich bag samples showed a slight decrease in hardness, cohesiveness, chewiness, and resilience, with differences between packaging treatments being significant for the 10-month samples. Results indicated that precooked catfish fillets can be stored for 10 months with little loss of quality, which supports the use of precooked catfish in frozen products.