Charolais bull calves (106) were used to study the variability in meat qual
ity attributes in relation to the variability in muscle characteristics in
the Longissimus thoracis (LT) muscle. The variability in traits was adjuste
d either to constant age or constant weight at slaughter and thus originate
d only from differences between animals born. reared and Fattened in the sa
me location. The following meat quality attributes were measured: the stren
gth of the myofibrillar resistance to a 20% compression strain measured on
the raw meat 2, 7 and 21 days post mortem; and taste panel scores of tender
ness (initial and overall), flavour and juiciness of steaks grilled to a 55
degreesC core temperature 6 or 15 days post-mortem. The following muscle c
haracteristics were measured 24 h after slaughter: pH, dry matter. protein,
lipid, heme iron and collagen contents, collagen solubility, LDH and ICDH
activity, the proportion of slow twitch myosin heavy chain, the mean muscle
fibre area and the mean sarcomere length.
One fourth to one third of the variability of 2 day mechanical strength and
15 day tenderness or flavour scores were related to the variability in mus
cle characteristics. Tenderness and strength measurements were predominantl
y related to the muscle fibre area, collagen characteristics and energetic
metabolic activity. Dry matter content was the principal muscle characteris
tic related to flavour. (C) 2001 Elsevier Science Ltd. All rights reserved.