Effect of Pre-cooking and Addition of Phosphate on the Quality of Microwave Cooked Catfish Fillets

Authors: Li, Carissa; Bland, John; Bechtel, Peter

Submitted to: Annual Meeting of the Institute of Food Technologists
Publication Type: Abstract Only
Publication Acceptance Date: 3/19/2016
Publication Date: 7/17/2016
Citation: Li, C.H., Bland, J.M., Bechtel, P.J. 2016. Effect of Pre-cooking and Addition of Phosphate on the Quality of Microwave Cooked Catfish Fillets. Annual Meeting of the Institute of Food Technologists. http://ift.planion.com/Web.User/AbstractDet?ACCOUNT=IFT&ABSID=15280%CONF=IFT16&ssoOverride=OFF&CKEY=.

Interpretive Summary:

Technical Abstract: In the US market place there are many examples of precooked poultry products designed to be reheated in a microwave oven and to a lesser extent fish products such as tilapia. However, there are few US catfish products designed to be microwave cooked or reheated in the market place. The first objective of this study was to examine the properties of raw frozen catfish fillets microwave cooked or oven precooked frozen fillets reheated by microwave cooking. The second objective was to evaluate the effect of a commercial phosphate blend on properties of microwave cooked or oven precooked raw frozen catfish fillets. Both fresh and frozen (containing a commercial phosphate blend) fillets were purchased from a commercial Mississippi catfish processor and stored frozen. Fillets (5-7 oz) were trimmed and cut into three pieces each weighing approximately 50 g. For the experiment 6 fillet pieces were used for each treatment. Treatments included plus and minus oven precook and plus and minus phosphate. After microwave cooking, sample analysis included weight loss, moisture content, color (L*a*b*) using a Minolta colorimeter, pH, and mechanical texture (hardness). Precooked pieces of fish were cooked in a 121°C oven until an internal temperature of 60°C was obtained, followed by storing frozen until analyzed or cooked to 93-99°C in a microwave. Preliminary microwave cooking studies determined that cooking at 870 W for 2.5 minutes was the best for a uniform cooking condition of the ~50 g catfish fillet pieces. Cooked fillets showed less than 3% moisture loss when they contained phosphate, relative to a 9.4% moisture loss for fillets without phosphate. A large cooking loss of ~40% was observed for precooked fillets after microwave cooking, correlated to a higher moisture loss (8.5% and 9.6% for fillets with and without phosphate, respectively) to comparable samples that were not precooked. Fillet hardness determined by peak force per thickness revealed similar texture properties between treatments for fillets without phosphate, while precooked fillets containing phosphate had an overall harder texture than non-precooked fillets after microwave cooking. This study will be used to develop precooked catfish products that can be reheated in a microwave.