Pork of low technological quality with a normal rate of muscle pH fall in the immediate post-mortem period: The case of the Hampshire breed.

The aim of the experiment was to determine the technological properties of meat from Hampshire pigs, as compared to good quality meat from Large White pigs and to exudative meat from halothane-positive (HP) Pietrain pigs. All Hampshire and Large White pigs were halothanenegative (HN). In 129 females and castrated males (47 Large White, 20 HN Pietrain, 27 HP Pietrain, 35 Hampshire), several quality characteristics were measured on raw meat and one ham was processed into cooked 'Paris ham'. Although the pH was normal I h post mortem in Hampshire pigs (which, in this respect, did not differ from Large White pigs) pork from Hampshire pigs, especially females, showed a very low ultimate pH and the highest cooking loss in processing. However, meat was much less exudative when fresh and generally darker (reflectance measured at 630 nm or subjective colour score) in Hampshire than in HP Pietrain pigs. A low ultimate pH occurred in muscle from Hampshire pigs owing to a very high 'glycolytic potential' (essentially glycogen content). It is proposed to use the term 'Hampshire type' to denote meat whose qualitative inadequacies basically result from an abnormally lowered ultimate pH, and to keep the term 'PSE' to refer to meat whose exudative state comes from an abnormally rapid pH fall in the immediate postmortem period.