1270
Aged beef from Nellore young bulls fed crude glycerin in diets with different roughage sources
This trial aimed to evaluate the effects of feeding crude glycerin (CG) - 80% glycerol - included on 10% of DM diet, replacing corn with three roughage sources: corn silage (CS), sugar cane (SC) and sugar cane bagass (SCB) on pH, water holding capacity (WHC), Warner-Bratzler shear force (WBSF) and cooking losses (CKL) of aged beef from Nellore young bulls fed in feedlot. Thirty animals with 416 ± 24.68 kg initial BW were randomly assigned to three treatments, with ten replicates and fed during 90 d in feedlot. Animals were slaughtered at average BW of 550.50 kg BW and all carcasses were refrigerated at 0°C for 24 h. Longissimus muscle (LM) section 10 cm thick was removed from the posterior end of the wholesale rib, individually vacuum-packaged and aged for 7 and 14 d at 0 - 2°C. The WHC was measured for the difference between the weights of the sample before and after it was subjected to a pressure of 10 kg for 5 min. Steaks of 2.54 cm were removed and same samples were used to analysis of WBSF and CKL. The experiment was conducted according to a completely randomized design in a factorial arrangement 3x3 (three diets x three aging times). Data were analyzed by the PROC MIXED procedure of SAS, and the Tukey test used considering 5% probability. The WHC (P = 0.68), WBSF (P = 0.15) and CKL (P = 0.88) did not differ among diets, however, the beef from animals fed SC had a higher pH values than animals fed other diets (P < 0.01). The WHC was not different between beef aged in 7 or 14 d (P = 0.72). The pH was higher and CKL was lower (P = 0.02) in beef aged for 14 d. The WBSF was lower in d 14 than d 7(P < 0.01). The use of corn silage, sugar cane or cane bagass in diets with crude glycerin replacing corn in 10% of DM did not affect the tenderness, WHC and CKL, but animals fed sugar cane had beef with higher pH values. The aging time until 14 d reduces the cooking losses and is an effective method to improve the tenderness of beef from Nellore young bulls.
Keywords: aging times, glycerol, meat quality