Modelling post-mortem tenderisation-I: Texture of electrically stimulated and non-stimulated beef

Texture in electrically stimulated and non-stimulated beef M Pectoralis profundus, stored under a range of temperatures from 0 to 30°C, while avoiding muscle shortening, was measured from 1 to 21 days after stunning. The pre-rigor temperature (from 0 to 30°C), maintained until the pH had fallen to 6·4 and then held at 15°C, had no effect on the toughness nor on the rate of tenderisation after rigor. Modelling toughness prior to 24 h suggested that toughness of all muscles could be rationalised and that first-order tenderisation began when the muscles reached pH 6·1 when the toughness of all the muscles was projected to be 12·5 kg. After pH 6·1, the rate of tenderisation at 30°C was 10-fold higher than at 1°C and was not affected by variations in pH from 6·1 to 5·5. At the higher temperatures, the ultimate toughness of aged meat was slightly higher than at the lower temperatures.