Callipyge genotypic effects on meat quality attributes and oxidation stability of ovine M. longissimus

Abstract The objective of this study was to evaluate the effects of callipyge ( C ) genotypes on quality attributes and oxidation stability of aged lamb loins. Only lambs possessing a wildtype maternal allele and a paternal callipyge allele ( +/C ) express a muscle hypertrophy phenotype. Seventeen lambs (7 months), consisting of all four possible callipyge genotypes ( C/+ , C/C , +/C and +/+ ), were harvested. Loins ( M. longissimus thoracis ) were separated from each carcass at 3 days postmortem, cut into 3 sections, and randomly assigned into three aging periods (3, 6 and 9 days). Genotype had no impact on proximate composition, mineral content, and pH of lamb loins (P > 0.05). In terms of water-holding capacity, slightly increased purge/thaw loss of +/ C lamb loins was observed (P   0.05). The highest shear force was found at +/C lamb loins (P  +/C lamb loins showed initially less redness, but greater color stability during 7 days of display compared to loins from the other genotypes. Heme iron content of +/C lamb loins was a significantly lower than the other genotypes. Genotype had no impact on lipid oxidation stability (P > 0.05). Our results indicate similar quality attributes of lamb loins between non-callipyge phenotypes ( C/C, C/+ and +/+ ) and suggest that callipyge lamb loins have superior color stability, while exhibiting lower tenderness compared to loins from non-callipyge phenotype lambs.