MEAT AGING MEASUREMENT - COMPARISON BETWEEN 2 MECHANICAL METHODS

The resistance of myofibrillar structure to a 0.2 strain was measured during ageing with two compressive methods on raw meat samples from old cows Longissimus Dorsi muscles. One measurement used a 10 Hz sinusoidal compression cycle performed on the Systeme d'Analyse de 1a Texture des Aliments. The other measurement used a classical linear compression system, with a probe speed of 50 mm/min. There was a close linear relationship (r = 0.96, P < 1 %) between the maximum stresses obtained in both methods. With linear compression, for a meat sample submitted to a 0.2 strain, myofibrillar structure developed a maximum stress which was about 35 N/cm(2) when measurements were done near rigor mortis. This value decreased to about 4 N/cm(2) when meat was aged. Theses values of stresses were slightly lower than those obtained with sinusoidal compression. The two methods were as suitable for measurement of meat ageing. Nevertheless they did not give exactly the same stresses values because samples were not tested with the same strain history in both method and meat has a slight speed-dependent mechanical behaviour.