Ca(2+)-activated protease in stored muscle
A Suzuki1, Y Matsumoto, T Sato
1Department of Animal Science, Faculty of Agriculture, University of Niigata, Igarashi, Niigata 950-21, Japan.
Meat Science
|November 8, 2011
Summary
Calcium-activated protease (CAF) plays a key role in meat tenderness. Higher CAF activity in stored muscle, compared to fresh muscle, confirms its importance in improving meat texture.
Area of Science:
- Biochemistry
- Food Science
- Muscle Biology
Background:
- Meat tenderness is a crucial quality attribute influenced by post-mortem biochemical changes.
- Calcium-activated protease (CAF) is implicated in the degradation of muscle proteins, affecting texture.
Purpose of the Study:
- To investigate the role of Calcium-activated protease (CAF) in meat tenderness.
- To characterize CAF properties and its effects on myofibril ultrastructure in stored muscle.
Main Methods:
- Extraction and activity assays of CAF from post-mortem muscle.
- Enzymatic property analysis (time course, pH, Ca2+ dependence).
- Electron microscopy to observe CAF's effect on myofibril structure.
Main Results:
- Crude CAF yield and activity were higher in stored muscle than in fresh muscle.
- CAF exhibited similar enzymatic properties (time course, pH, Ca2+ dependence) regardless of storage.
- Electron microscopy confirmed CAF's activity under conditions present in stored muscle.
Conclusions:
- Calcium-activated protease (CAF) is confirmed to play a significant role in developing meat tenderness.
- CAF activity increases during meat storage, contributing to textural changes.
- Understanding CAF function can inform strategies for meat quality improvement.
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