Effect on lamb meat quality of including thyme (Thymus zygis ssp. gracilis) leaves in ewes’ diet

The aim of this study was to investigate the effect of including thyme leaves (TL) in the diet of pregnant sheep on the sensorial characteristics, bacterial spoilage and oxidative stability of lamb meat stored in modified atmosphere (70% O2:30% CO2). For this, thirty-six sheep were randomly assigned to three groups: control (basal diet), T1 (3.7% thyme leaves), T2 (7.5% thyme leaves). Meat spoilage (TV, PSY, MY, ENT, and LA), TBARS, CIELAB coordinates, metmyoglobin and the sensory characteristics of fresh lamb meat were analyzed on days 0, 7, 14 and 21. The presence of antioxidant compounds in the diet containing TL delayed (P < 0.05) colour deterioration, lipid oxidation and bacterial counts, while at the same time imparting a better appearance to the fresh lamb meat. In general, this effect was more pronounced at the higher level of TL (7.5%). High Pearson’s correlation coefficients were found between the sensory attributes, CIELAB coordinates and TBARS.