Postmortem Proteolysis of Breast and Leg Muscles from Taiwan Colored Chickens and Silkie Bantams

Abstract

Postmortem proteolysis of breast (BM) and leg (LM) muscles from Taiwan colored chickens (TCC) and silkie bantams (SB) at 5°C were compared. Myofibrils were prepared from BM and LM samples that were randomly taken from the carcasses of SB and TCC after 0, 1, 3, 7 and 14 days of storage at 5°C. pH of samples was determined, and degradation of myofibrillar proteins was analyzed by the SDS-PAGE and western blots. The results showed that pH was lower in BM than in LM samples from both avian strains. Appearance of 30 kDa components and disappearance of titin and nebulin were more rapidly as seen on SDS-PAGE in BM than in LM samples. Western blots labeled with a monoclonal antibody to desmin also demonstrated that desmin degraded more quickly in BM samples. Our data might suggest that postmortem proteolysis occurred more rapidly in BM than in LM from both TCC and SB.

Postmortem degradation of desmin and calpain in breast and leg and thigh muscles from Taiwan black-feathered country chickens

“…These results were consistent with the findings of Lee et al ,23 who showed that the ultimate pH in chicken muscle was reached by 6 h post mortem. Figure 1 also shows that the pH was significantly ( P < 0.05) lower in the BM than in the LM samples after 24 h postmortem storage at 5 °C, consistent with our previous report 24. This difference might be attributed to the higher content25 and to the faster utilization23 of muscle glycogen in chicken breast muscle.…”

“…2) decreased more rapidly than LM desmin (Fig. 2), confirming previous studies 24. In BM samples, most of the desmin remained intact in 3 h postmortem samples, which contained ∼85% of the desmin present in BM sampled at death.…”

Postmortem role of calpains in Pekin duck skeletal muscles

“…Figure 1 shows that the pH was significantly lower ( P < 0.05) in BM than in LM during 14 days postmortem storage at 5 °C, similar to our previous findings in chicken muscle 17, 28. The average at‐death pH was 6.25 ± 0.13 in BM samples and decreased significantly to 5.96 ± 0.11 ( P < 0.05) by 1 day post mortem (Fig.…”

“…Western blots labeled with a desmin monoclonal antibody indicate that BM desmin decreased more rapidly than LM desmin (Fig. 2), consistent with the changes in postmortem chicken muscle 17, 28. In BM samples, the abundance of desmin in 1‐day postmortem samples decreased to ∼57% of the abundance in the at‐death samples.…”