@conference {41771,
	title = {Examination of pH in lot fed beef for Japan},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {67},
	year = {2007},
	month = {Jan},
	pages = {436-440},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Wanaka},
	abstract = {Cattle lot fed for the Japanese market produce carcases of high value and thus downgrading based on meat quality represents a significant cost. The Meat Standards Australia guidelines for the rate of pH fall specify that carcases must not reach pH 6.0 before their temperature reaches 35{\textdegree}C, however limited experimental data suggests this is a common occurrence in heavy carcases produced for the Japanese market. Therefore a study was conducted to confirm this occurrence and to determine the impact of season on the incidence of fast pH fall. 811 carcases were examined from cattle fed for ~150 days, 411 in April and 400 in July. Initial pH (pHi) and temperature were measured on all carcases and then a sub-set of samples (200/season) were measured for traits such as colour, drip loss and protein solubility. pHi was measured on core muscle samples taken from the loin muscle between the 5th/6th ribs prior to entering the chiller. The pH at 35{\textdegree}C was predicted for a subset of 41 carcases based on data collected at the MSA site at the lumbarsacral junction using non linear regression. There was a significant relationship (P < 0.05) between pH at 35{\textdegree}C at the MSA site and the temperature at the sampling site at the 5th/6th rib used for determination of pHi. A large proportion of the carcases were outside the MSA pH/temperature window in both autumn (86\%) and winter (95\%). Season was found to have a significant effect on pH at 35{\textdegree}C (P < 0.001) and ultimate pH (P < 0.001) with higher values in the autumn and winter respectively. A high incidence of carcases exhibiting a fast pH decline at high temperatures was found, irrespective of season and the significance of this finding is discussed.},
	issn = {1176-5283},
	author = {Hopkins DL and Cassar JA and Toohey ES and Wynn PC}
}
