Volatile and sensory analysis to discriminate meat from lambs fed different concentrate-based diets

Context. Diet is one the most important pre-slaughter factors that potentially influences meat quality, but its effect on flavour quality remains equivocal. Aim. The aim of the present study was to investigate the effect of diet composition on the flavour and sensory quality of meat from Texel x Scottish Blackface ram lambs. Methods. Groups of 11 lambs were assigned to one of the following four dietary treatments for 54 days before slaughter: a concentrate containing barley, maize and soybean (C treatment); C supplemented with a saturated fat source (Megalac (R)); C supplemented with protected linseed oil; a by-product-based diet containing citrus pulp, distillers grain and soybean. Samples of cooked M. longissimus thoracis et lumborum were subjected to volatile analysis involving solid-phase microextraction followed by gas chromatography-mass spectrometry and to sensory analysis performed by a trained panel. Key results. Univariate analysis of volatile data and sensory data showed few differences due to dietary treatments. However, multivariate analysis of the volatile data, and to a lesser extent the sensory profile data, showed potential to discriminate between lamb meat samples, on the basis of the different dietary treatments. Conclusions. The inclusion of certain dietary ingredients in the diets of lambs to enhance the nutritional profile of lamb meat (through increasing n-3 fatty acid content) or to reduce feed-formulation costs (through the use of by-products) has minor effects on sensory quality but permits some discrimination between dietary treatments following the application of multivariate analysis.