Effects of Phosphate Type on the Quality of Vacuum-Tumbled Catfish Fillets

Abstract
The objective of this study was to determine the effects of various agglomerated phosphate blends on the quality of vacuum-tumbled catfish fillets. Catfish fillets were tumbled with a brine solution at 15% over initial, raw weight prior to tray-packing and storage at 4°C for 10 days. Fillets were evaluated for protein exudate, tumbling yield, color, pH, cooking loss, tenderness, purge loss, and shelf life. A specific blend of agglomerated sodium phosphates (AGSP) that contains mono-, tri-, and polyphosphates had significantly less protein (p < 0.05) exudate and significantly higher pH (p < 0.05) than other treatments. All phosphate treatments significantly increased (p < 0.05) tenderness and significantly decreased (p < 0.05) purge loss, but agglomerated phosphate blends significantly decreased (p < 0.05) cooking loss and yellowness. Psychrotrophic plate counts for all phosphate treatments were similar to the control at each storage time. All phosphate treatments improved the yield and quality of catfish fillets, but the use of AGSP may optimize quality attributes.