Effect of dry aging on quality parameters, protein profile and protein oxidation level of beef

The effect of dry aging process (15 and 30 days) on some quality parameters, protein profile and formation of protein oxidation products of beef was investigated. The maximum weight and trim loss were calculated to be 47.07% and 23.06%, respectively. The meat dry-aged for 30 days had higher dry matter, pH and protein content, but lower L* and a* values than those of the unaged meats. There was a significant decrease in actin protein band density in the meat dry-aged for 30 days and a new protein band of 32 kDa appeared in the myofibrillar protein fraction. The dry aging process caused an insignificant increase in the total carbonyl content (P > 0.05). However, the γ-glutamic semialdehyde (GGS), α-aminoadipic semialdehyde (AAS) and total GGS and AAS contents were higher in the dry-aged meats for 30 days. Total GGS and AAS contents ranged from 15.36% to 31.87% of the total carbonyl content. It was found that there was no significant difference between control group (unaged) meats and the meat dry-aged for 15 days in terms of protein oxidation products.