Qualidade da carne de cordeiros alimentados com dietas contendo glicerina bruta

Abstract

The aim was to assess the quality of lamb meat Pantaneiro fed increasing levels of crude glycerin in the diet replacing corn. Were used 24 lambs, non-castrated males, the experiment was conducted in a completely randomized design with four treatments and six replications. The treatments were 0, 2.5, 5.0 and 7.5 % of crude glycerin inclusion (GB) on dry matter (DM) basis replacing corn. The animals were slaughtered when they reached a body condition score of 2.5 to 3.0. After slaughter and subsequent cooling of the carcass for 24 hours in a cold, muscle Triceps brachii (shoulder), Longissimus (loin) and Semimembranosus (leg) were taken for analyzes of water holding capacity (WHC), cooking loss (CL), shear force (SF) and colorimetry (L*, a* and b*), chemical composition (moisture, protein, ether extract and ashes) and sensory (odour, flavour, tenderness and overall acceptability). All traits were subjected to the Shapiro-Wilk test to verify the normality of the residuals and Bartlett to verify homogeneity of variance. Parametric data were submitted to regression at 5 % significance. The chi-square test was used for the sensory characteristics when observed and expected frequencies in the contingency table were greater than or equal to five, in other cases the Fisher exact test was used. The inclusion of different levels of crude glycerin did not affect the instrumental characteristics of the Triceps brachii and Longissimus muscles. The color of the Semimembranosus muscle, was effective with inclusion of crude glycerin (p<0.05) only for the characteristic intensity of yellow (b*) that showed a quadratic effect. The ether extract content of the Triceps brachii presented linear effect and in the Longissimus showed linear increase. There was no effect of adding increasing levels of crude glycerin for sensory characteristics odor, flavour, tenderness and overall assessment of the different muscles. The inclusion of increasing crude glycerol (39.3 % glycerol) replacing corn in the diet of lambs modifies the intensity of yellow Semimembranosus muscle and the ether extract content of the Triceps brachii and Longissimus muscles. However, the sensory characteristics were not affected by diets, featuring a good quality meat for consumers, and it can be included up to 7.5 % of dry matter diet, replacing corn.