Muscle pH and temperature changes in hot- and cold-deboned ostrich (Struthio camelus var. domesticus) Muscularis gastrocnemius, pars interna and Muscularis iliofibularis during the first 23h post-mortem.

Cold-shortening is the response when muscles are exposed to temperatures below 10°C with a pH>6.20. The course of pH within hot-deboned and intact ostrich M. gastrocnemius, pars interna and M. iliofibularis were followed for the first 23-24h post-mortem to investigate the changes in pH as well as to determine the point of minimum pH for ostrich muscles post-mortem. The hot-deboned muscles took longer to reach the point of minimum pH than the intact muscles. There was no significant (P=0.4508) difference in the minimum pH (5.91±0.26) between the hot-deboned and the intact muscles. It was concluded that both the M. gastrocnemius, pars interna and the M. iliofibularis reached a pH<6.20 early post-mortem with muscle temperatures above 10°C; and therefore showed no risk of cold-shortening if these muscles were to be hot-deboned 2-4h post-mortem.