Integrated studies on the freshness of rainbow trout (Oncorhynchus mykiss Walbaum) postmortem during chilled and frozen storage

• Published in: Journal of food biochemistry Vol. 28; no. 3; pp. 213 - 244
• Main Authors: Wills, C.C, Proctor, M.R.M, McLoughlin, J.V
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01-08-2004; Blackwell
• Subjects: adenines; adenosine triphosphate; appearance (quality); biochemical compounds; Biological and medical sciences; fish; Fish and seafood industries; Food industries; food storage; freshness; frozen storage; Fundamental and applied biological sciences. Psychology; off odors; Oncorhynchus mykiss; oxidative phosphorylation; refrigeration; rigor mortis; shear stress; shelf life; slaughter; storage time; texture; Edible fish; Warehousing; Trout; Postmortem; Food preservation; Freshness; Frozen product
• ISSN: 0145-8884; 1745-4514
• DOI: 10.1111/j.1745-4514.2004.tb00067.x

Rainbow trout were killed by two methods, asphyxiation and clubbing. The concentration of ATP in specimens of skeletal muscle taken immediately after death was significantly (P<0.01) higher in clubbed (4.41 ± 0.86 μmol/g) than in asphyxiated (2.00 ± 0.69 μmol/g) fish. The shear force (Warner-Bratzler) required to cut the muscle was higher (P<0.05) in clubbed (8.33 ± 0.61 N) than in asphyxiated (6.85 ± 0.98 N) fish. Changes in the concentration of adenine nucleotides and in shear force were measured at intervals during storage at 3C and - 30C. The K value was calculated and was found to be correlated inversely with changes in shear force, Torrymeter readings and sensory assessment. There were no significant differences in the concentrations of ATP and metabolites between muscle sites. There were no differences in shear force measurements between the locations sampled nor between muscle taken from the right and left sides of the fish.