IGlycogen Degradation Postmortem
The contents of free glucose, proglycogen, and macroglycogen
in LM sampled at 0, 2, 8, 24, and 72 h
postmortem from Step15 and Con15 carcass halves are
shown in Figure 2. There was no effect (P > 0.05) of
chilling treatment on the content of free glucose, macroglycogen,
or proglycogen. The content of free glucose
did not increase until after 2 h postmortem and continued
to increase (P < 0.01) up to 72 h postmortem.
In contrast, the content of macroglycogen decreased as
early as 0 to 2 h postmortem (P < 0.01) and continued
to decrease until 24 h postmortem (P < 0.01), whereas
there was no further change from 24 to 72 h. Likewise,
the content of proglycogen decreased as early as 0 to
2 h postmortem (P < 0.01) and continued to decrease
throughout the studied period until 72 h postmortem
(P < 0.01).
The activity of GDE in LM biopsies from Step15 and
Con15 carcass halves is presented in Figure 3. There
was no effect (P > 0.05) of chilling treatment on the activity
of GDE. The activity decreased with time postmortem
as early as 0 to 2 h postmortem (P < 0.01) and continued to decrease in the period studied (24 h
postmortem), although the curve began to flatten out
from 8 to 24 h postmortem.