The shear force of very-rapidly chilled lamb - 2: The effect of muscle excision

The effect of chilling rate and muscle excision on the shear force of ovine muscle (M. longissimus thoracis et lumborum) was examined. Conventional ch illing involved chilling at 4C for 24 h and very-rapid chilling involved ch illing at -20C for 3.5 h followed by conventional chilling for 20.5 h. Afte r 24 h all muscles were aged for a further four days. Approximately 30 min after slaughter, one M. longissimus thoracis et lumborum was excised from e ach carcass and placed in the same chill as the remainder of the carcass. T his gave a total of four different treatments. Shear force was assessed at I and 5 days postmortem by Warner-Bratzler shear force measurement. Excisio n led to reduced shear force in the very-rapid chilling regime but increase d shear force in the conventionally chilled muscles. Aging improved shear f orce for all chilling treatments. No significant difference was found in th e rate of pH fall, between the chilling treatments.