The effect of genotype and muscle type on the physico-chemical characteristics and taurine, carnosine and L-carnitine concentration in lamb meat

Abstract

Abstract. An experiment was conducted to determine the chosen bioactive components and physico-chemical characteristics of lamb meat of different animal genotypes and the muscle types. The 22 ram lambs of Polish Merino (PM) and 22 crossbreeds of Polish Merino × Berrichone du Cher (PMB) were fattened to achieve their slaughter weight of 40 kg. After slaughter, the carcasses were kept at 4 ∘C for 24 h. Then, the samples of longissimus lumborum (LL) and gluteus medius (GM) muscle were collected to analyse the physico-chemical traits; fatty acid profile; and concentrations of taurine, carnosine, L-carnitine. The GM muscle compared to LL had the higher value (P < 0.05) of L* and a lower value (P < 0.05) of b* and H* both in PM and PMB lambs. The value of expressed juice was lower (P < 0.05) in both LL and GM muscles of PM lambs. A higher amount (P < 0.05) of collagen was found in LL muscle compared to GM both in PM and PMB lambs. The GM muscle of PM lambs showed higher (P < 0.05) conjugated linoleic acid (CLA) content, as well as higher total polyunsaturated acids (PUFAs), PUFA n-6, and PUFA n-3 (P < 0.05). The GM muscle was characterized by a higher (P < 0.05) content of taurine, while in the LL muscle there was a higher amount (P < 0.05) of carnosine. A larger amount (P < 0.05) of L-carnitine was found in GM muscle but only within PMB lambs. The obtained results showed a greater impact of the lamb's genotype on the physical characteristics of meat than on its chemical composition and the content of bioactive components. The muscle type had an effect on meat colour; collagen content; fatty acid profile; and amount of taurine, carnosine, and L-carnitine present.