Effect of chilling rate on heat shock proteins abundance, myofibrils degradation and caspase‐3 activity in postmortem muscles

Abstract

SummaryThe objective of this study was to investigate the effect of chilling rate on heat shock proteins (HSP) abundance, myofibrillar proteins degradation and caspase‐3 activity of lamb muscle in postmortem. Eighteen longissimus dorsi (LD) muscles from lamb were treated under three different chilling rates—very fast chilling I (VFC‐I, 22.2 °C h−1), very fast chilling II (VFC‐II, 32.4 °C h−1) and control (1.44 °C h−1)—and stored at −1 °C, −1 °C and 4 °C for 120 h postmortem, respectively. The results showed that myofibril fragmentation index (MFI), the abundance of αβ‐crystallin and HSP20, as well as the degradation of HSP27, HSP70, troponin‐T and desmin under the VFC‐I and VFC‐II groups were higher than control. Notably, HSP90 abundance may not be affected by the chilling rate in the late postmortem aging. Additionally, with increasing of chilling rate for postmortem muscle could inhibit caspase‐3 activity. Overall, results indicated that chilling rate may affect the process of meat tenderization by changing the abundance levels of heat shock proteins, myofibrillar degradation and apoptotic pathway.