Addition of herbal extracts to the Holstein-Friesian bulls' diet changes the quality of beef.

Twenty four Holstein-Friesian bulls were randomly assigned to one of three dietary treatments: a control diet, diet O (supplemented with Optirum herbal extracts improving the functioning of the gastrointestinal tract of cattle), and diet OS (containing two herbal preparation: Optirum and Stresomix, used to reduce stress). The quality of longissimus lumborum (LL) and semimembranosus (SM) muscles were determined after 14 days of wet ageing. The diet influenced proximate composition, pH, water holding capacity, colour, shear force and some sensory quality attributes of beef, although the influence depended on the muscle type. The supplementation of the bulls' diet with two herbal preparations (OS diet) had a beneficial impact on technological properties and sensory tenderness of LL muscles. The herbal extracts O and OS had no negative effect on lipid oxidation or the sensory attributes of beef. Thus, it is recommended to use a combination of these two products in cattle feeding.