Effect of different sources of lipids in diet on the qualitative characteristics of Longissimus thoracis muscle of cattle finished in feedlots

The objective of this study was to determine the effect of the dietary inclusion of lipid-based diets (whole cottonseed and protected fat) on the pH, meat color and fat, tenderness and cooking yield in Longissimus thoracis muscle of cattle feedlot. Were used 39 Nellore cattle uncastrated with average initial body weight of 494.1 ± 10.1 kg and 36 months of age were housed for 63 days in pens with thirteen animals each. A completely randomized design with three treatments and thirteen replications was used. The treatments evaluated were: Feed with 2.50% whole cottonseed (control diet); feed with 11.50% whole cottonseed; and feed with 3.13% whole cottonseed added of protected lipid (PL), all on a dry matter basis. No differences were found for pH 24 h post mortem, meat color and fat, tenderness or cooking yield. The values of shear force of meat the animals presented differences (P <0.05), and the animals fed with 11.50% of cottonseed had greater value than those fed 2.50% on the diet, in relation to dry matter. The study came to the conclusion that the protected lipid does not influence the qualitative characteristics of meat and the amount of 11.50% of cottonseed in the cattle diet does not contribute to the improvement of texture and tenderness of the meat.   Key words: Color, cooking yield, shear force, whole cottonseed.