An analysis of instrumental texture differences between channel (Ictalurus punctatus) and hybrid (female channel × male blue, I. furcatus) catfish fillets is presented. Factors including cold-storage type (fresh, frozen, or individually quick frozen (IQF)) and gender were included in the comparisons. Texture was measured at eight positions per fillet by a texture profile analysis (TPA) method that provided seven texture attributes: firmness, toughness, cohesiveness, adhesiveness, chewiness, resilience, and springiness, plus the thickness of the fillets (238 total). All attributes except adhesiveness were found to be statistically different (p < 0.05) between channel and hybrid fillets, with channels having the highest value in each attribute. When cold-storage type was included in the analysis, channels still produced the highest attribute values, but the number of attributes differed with firmness, toughness, and chewiness most associated with the differences in the type of catfish, while the other attributes were affected by cold-storage type. Thickness was found to be a strong covariant to some of the texture attributes, especially toughness, but the determination of difference between channels and hybrids was not affected and TPA profiles provided high levels of differentiation between catfish types.
Keywords: channel catfish; cold-storage type; hybrid catfish; instrumental texture profile analysis; thickness covariance.