Heat and ultrafiltration extraction of broiler meat carnosine and its antioxidant activity

This study examined the effects of extraction and further ultrafiltration on the carnosine content, antioxidant activity and total iron content of chicken muscle extracts. Fresh breast meat had 7-fold higher carnosine than fresh thigh meat (2900 versus 419 μg/g meat, respectively). Carnosine extracts of breast and thigh were prepared by heating at 60, 80 and 100 °C, and ultrafiltration (UF) using a 5000 MW cut-off. At increasing temperatures, protein concentrations decreased while carnosine, total iron and antioxidant activity increased. Antioxidant abilities of the 80 and 100 °C-heated extracts were greater than that of the 60 °C extract (p < 0.05). The ultrafiltrate from the 80 °C-heated extract had approximately 20% higher carnosine, but 40% lower protein and 10–30% lower iron than the 80 °C-heated ultrafiltrate. However, compared in terms of carnosine concentration, the meat extracts had greater antioxidant activity than pure carnosine (p < 0.05).