A note on some factors influencing muscle pH values in commercial pig carcasses

Abstract

Measurements of longissimus dorsi pH at 45 min post mortem (pH₁) were taken in 27 727 pig carcasses at four bacon factories. The overall least squares mean pH₁ was 6·26 and 15·5% of carcasses had pHi values of 5·9 or less. Sex and commercial grade of carcass had little influence on muscle pHi or the incidence of values below pH 6·0. Factory differences were recorded in the distribution of muscle and within each there were marked producer effects in mean and the incidence of values below pH 6·0. Carcasses of Large Whites had fewer muscle pH₁ values below 6·0 (12·4%) than those of British Landrace (18·7%), this being mainly due to a large breed effect at one factory. Although breed and testing background of sires of the carcasses examined and the first order interactions with factory had significant effects on muscle pHi and the incidence of values below pH 6·0, they were of little practical significance.