Post mortem muscle metabolism and meat quality in three genetic types of turkey

1. A standard (FG, fast-growing), a black local or 'label', type (SG, slow- growing) turkey line, and the crossbreed between these two lines were compa red for muscle post-mortem metabolism and related meat quality traits. 2. Ninety male turkeys (30 of each genetic type) were raised under the same experimental conditions until slaughter at 16 weeks of age. 3. Live weights at 16 weeks of age differed significantly (7.8, 6.0 and 4.2 kg, for the FG, crossbred and SG lines, respectively). Collagen content of Pectoralis superficialis (PS) muscle was higher in SG birds than in the ot her two types. 4. The rate of post-mortem glycogen depletion and lactate accumulation in P S and Ilio tibialis ( IT) muscles were similar in the 3 lines, as were the rate and extent of post-mortem pH fall in PS muscle. In IT muscle, however, SG birds showed a slight but significantly faster pH decline. 5. Colour measurements indicated a paler breast muscle and a higher degree of myoglobin oxidation in SG birds at 24 h post mortem, than in both other lines. But these differences had disappeared after 4 and 7 d post mortem 6. SG birds showed higher drip loss and instrumentally-assessed toughness i n breast muscle, compared with crossbred and FG birds. FG birds, however, h ad the lowest yield of breast meat after curing-cooking. 7. No marked differences in post-mortem metabolism were found between the t hree lines. However, differences in water-holding capacity of fresh and cur ed-cooked meat suggest that factors other than the rate and extent of post- mortem pH fall may contribute to the respective characteristics of these li nes.