Transaminase Affects Accumulation of Free Amino Acids in Electrically Stimulated Beef

Electrical stimulation (ES) of a beef carcass increases the content of free amino acids, which affects meat flavor. Levels of glutamic acid (Glu)‐aminopeptidase activity were similar in both control and ES meat but decreased during storage to about 65% at 14 days. When 2‐ketoglutaric acid (a substrate of transaminase) was added to the sarcoplasm, the level of Glu increased. Transaminase activity was unaffected by storage and was about 20% greater in ES than in the control. Transaminase activity in beef was confirmed when radioactive 2‐ketoglutaric acid was added to the sarcoplasm. Results suggest that transaminase contributes to accumulation of some amino acids such as Glu in beef during conditioning.