Abstract

The ultimate pH (pHult) of beef is an important quality determinant, that can be affected by pre-slaughter muscle glycogen concentrations. The two trials reported here evaluated relationships between pre-slaughter conditions and behaviour of mobs ofsteers processed at Manawatu Beef Packers Limited and the subsequent incidence of high-pH beef. Trial 1 involved 405 2- and 3-year steers in 12 mobs, with a mean (±sd) carcass weight of 341.2 (±28.2)kg. Cattle were held for either c. 3h prior to slaughter (1/2of each mob) or c. 27h. Mean carcass weight was lower for the 27h-mobs (P < 0.01), but the extra 24h holding time had no effect on mean pHult , bruising score, carcass fat depth, or meat colour. The percentage of carcasses with a pHult> 6.0 varied from 0 to 27%, but was not closely related to any of the pre-slaughter conditions monitored (eg. feeding levels, conditions during yarding, loading and transport,weather conditions, and conditions at the plant).

RW, Purchas, and BE Keohane

Proceedings of the New Zealand Society of Animal Production, Volume 57, , 271-274, 1997