Ultrastructural and biochemical changes in electrically stimulated dark cutting beef

In dark cutting beef, with a high ultimate pH, ultrastructural and biochemical changes were followed during the very early post-mortem period in non-stimulated and electrically stimulated muscles. The consumption of ATP was extremely rapid in the electrically stimulated dark cutting muscle. In these samples pronounced changes in the ultrastructure were seen in the form of heavy contractions and complete disorganization of the tissue. The changes could have been caused by a combined effect of super-contractions and proteolytic activity. The changes seen in electrically stimulated samples were not reflected in improvements of the instrumentally evaluated tenderness.