THE EATING QUALITY OF PORK .1. THE INFLUE NCE OF ULTIMATE PH

Twenty pork carcasses were selected at 13 h post mortem (pm) to contai n longissimus lumborum (LL) muscles that possessed a large variation i n ultimate pH. On the LL ultimate pH, colour, water holding capacity, sarcomere length, percent intramuscular fat and shear force (at 3 and 7 days pm) were assessed. In addition, eating quality (tenderness, jui ciness and flavour) was determined at 5 till 8 days p.m. by a 25-membe r taste panel. Ultimate pH varied from 5.42 to 6.25 (mean: 5.71) and w as, as expected, significantly related to colour and water holding cap acity. The PSE condition was not observed. Shear forces, particularly at 7 days pm, were highly correlated with panel judgements of tenderne ss (r=-0.78) and juiciness (r=-0.74). No significant relationships wer e found for sarcomere length or intramuscular fat with shear forces an d panel judgements. Ultimate pH was positively related to sensory tend erness (r=-0.78) and juiciness (r=-0.68), but not to flavour (r=-0.02) . Furthermore, ultimate pH appeared to be more highly related to shear force at 7 days (r=-0.70) than at 3 days (r=-0.43) pm. This suggests that ultimate pH had an effect on ageing rate. The results indicate th at carcasses can be selected for eating quality (tenderness and juicin ess) by using ultimate pH.