Stable isotope ratio analysis: A potential analytical tool for the authentication of South African lamb meat

Stable isotope ratios (13C/12C and 15N/14N) of South African Dorper lambs from farms with different vegetation types were measured by isotope ratio mass spectrometry (IRMS), to evaluate it as a tool for the authentication of origin and feeding regime. Homogenised and defatted meat of the Longissimus lumborum (LL) muscle of lambs from seven different farms was assessed. The δ13C values were affected by the origin of the meat, mainly reflecting the diet. The Rûens and Free State farms had the lowest (p ⩽ 0.05) δ15N values, followed by the Northern Cape farms, with Hantam Karoo/Calvinia having the highest δ15N values. Discriminant analysis showed δ13C and δ15N differences as promising results for the use of IRMS as a reliable analytical tool for lamb meat authentication. The results suggest that diet, linked to origin, is an important factor to consider regarding region of origin classification for South African lamb.