Beef carcasses with larger eye muscle areas, lower ossification scores and improved nutrition have a lower incidence of dark cutting

Abstract

This study evaluated the effect of eye muscle area (EMA), ossification, carcass weight, marbling and rib fat depth on the incidence of dark cutting (pHᵤ>5.7) using routinely collected Meat Standards Australia (MSA) data. Data was obtained from 204,072 carcasses at a Western Australian processor between 2002 and 2008. Binomial data of pHᵤ compliance was analysed using a logit model in a Bayesian framework. Increasing eye muscle area from 40 to 80 cm², increased pHᵤ compliance by around 14% (P<0.001) in carcasses less than 350kg. As carcass weight increased from 150 kg to 220 kg, compliance increased by 13% (P<0.001) and younger cattle with lower ossification were also 7% more compliant (P<0.001). As rib fat depth increased from 0 to 20 mm, pHᵤ compliance increased by around 10% (P<0.001) yet marbling had no effect on dark cutting. Increasing musculature and growth combined with good nutrition will minimise dark cutting beef in Australia.