Carotenoid, colour and reflectance measurements in bovine adipose tissue to discriminate between beef from different feeding systems

Our hypothesis was that carotenoids in bovine subcutaneous adipose tissue (SAT) together with colour and reflectance spectra could be used to differentiate between beef production systems based on grass, concentrates or combinations thereof. SAT was sampled from the carcasses of heifers fed pasture (P), a barley-based concentrate (C), silage followed by pasture (SiP) or silage followed by pasture with concentrate (SiPC). β-carotene in the SAT from the C group (0.09 μg g−1) was lower (Pb0.05) than that from the P (0.54 μg g−1), SiP (0.49 μg g−1) and SiPC (0.49 μg g−1) groups. Lutein in the SAT differed (Pb0.05) between all groups with 0.13, 0.10, 0.08 and 0.04 μg g−1 for the P, SiP, SiPC and C groups, respectively. Principal component analysis of the carotenoid data, SAT colour variables [‘L’, ‘a’, ‘b’, ‘C’, ‘H’] and the reflectance data made it possible to distinguish between the animals fed a barley-based concentrate diet and the animals fed pasture-based diets, but not between different pasture-based groups