Loading…

Proteolytic Activity and Calcium Effect in Dark–firm–dry and Pale–soft–exudative Meat

Changes in myofibrillar proteins and pH in dark–firm–dry (DFD) and normal beef, and in pale–soft–exudative (PSE), normal and DFD pork were monitored during post mortemstorage (2 °C). The DFD beef exhibited an overall increase in pH during storage; the pH changes in other muscle samples were inconsis...

Full description

Saved in:
Bibliographic Details
Published in:Food science & technology 1996, Vol.29 (1), p.123-128
Main Authors: Livisay, S.A., Xiong, Y.L., Moody, W.G.
Format: Article
Language:English
Subjects:
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Changes in myofibrillar proteins and pH in dark–firm–dry (DFD) and normal beef, and in pale–soft–exudative (PSE), normal and DFD pork were monitored during post mortemstorage (2 °C). The DFD beef exhibited an overall increase in pH during storage; the pH changes in other muscle samples were inconsistent. No detectable post mortemproteolysis was observed in myosin and actin from the SDS-PAGE analysis. In beef, the gradual appearance of a 30 kDa component after day 3 was the only definitive post mortemproteolytic change in both DFD and normal muscle. This proteolytic change was more pronounced in DFD and normal pork than in beef, and in pork, the occurrence of the 30 kDa polypeptide coincided with the disappearance of troponin-T/tropomyosin. The rate of these changes was generally greater in DFD than in normal pork. Compared with DFD and normal pork muscle, PSE pork had a delayed emergence of the 30 kDa component. Injection of CaCl 2solution (0.3 mol/L, at 5 g solution per 100 g muscle) did not appreciably alter proteolysis in all pork samples. Differences observed in the 30 kDa polypeptide between normal, PSE and DFD pork may be part of the reason why the anomalous pork differs from normal pork in textural quality.
ISSN:0023-6438
1096-1127
DOI:10.1006/fstl.1996.0016