ARS | Publication request: Effects of Transport Water Temperature, Aerator Type, and Oxygen Level on Channel Catfish, Ictalurus Punctatus, Fillet Quality

Submitted to: Journal Of The World Aquaculture Society
Publication Acceptance Date: June 8, 2004
Publication Date: September 20, 2004
Citation: Bosworth, B.G., Small, B.C., Mischeke, C. 2004. Effects Of Transport Water Temperature, Aerator Type, And Oxygen Level On Channel Catfish, Ictalurus Punctatus, Fillet Quality. Journal Of The World Aquaculture Society 35:410-417.

Interpretive Summary: Stress and activity associated with harvest and transport have been shown to negatively influence meat quality in salmonids and terrestrial livestock, but little information is available on the effects of transport environment on fillet quality of channel catfish. The effects of transport water temperature, oxygen level, and type of aerator on channel catfish fillet quality were determined. Although water transport temperature and aerator type affected some measures of water quality (ammonia, pH, CO2), they had no effect on fillet quality. Fish transported with higher water oxygen levels (9-10 mg/L) produced better quality fillets (lower weight loss during storage and less pale fillets) than fish transported at lower oxygen levels (4-5 mg/L). Increasing oxygen levels during transport could improve fillet quality of farm-raised catfish, but analysis of the costs associated with increasing oxygen levels and economic benefits associated with improved fillet quality is needed.

Technical Abstract: The objectives of this study were to determine the effects of transport water temperature (10 C vs. 20 C), type of aeration (blower vs. pure oxygen), and dissolved oxygen level (low = 4-5 mg/L vs. high = 9-10 mg/L) on transport water quality and fillet quality. Catfish were transported for 3.5 h at densities of approximately 0.8 kg/L, stunned by electricity, and processed. Relative to aeration by pure oxygen, aeration by blower resulted in significantly (p < 0.05) higher transport water pH (7.9 vs. 7.1), lower CO2 (7.5 vs. 52.9 mg/L), and lower ammonia (5.30 vs. 8.08 mg/L). All fish had elevated cortisol levels, but cortisol levels were not affected by treatment. Relative to transport at low oxygen levels, fillets from fish transported at high oxygen levels had lower drip-loss during storage (1.08 vs. 1.49%) and lower `L' values (53.13 vs. 54.87). Transport temperature and aerator type had no effect on fillet quality. Fillet drip-loss was positively correlated with 4 h `L' value (+0.43, p < 0.0001) and 72 h `L' value (+0.47, p < 0.0001), and negatively correlated with 72 h pH (-0.53, p < 0.0001). Increasing oxygen levels during transport could improve fillet quality of farm-raised catfish, but analysis of the costs associated with increasing oxygen levels and economic benefits associated with improved fillet quality is needed.