Antioxidant activity of mechanically separated pork extracts

Utilization of synthetic carnosine as a food additive is limited by both regulatory and economic hurdles. Therefore, the potential of producing carnosine-containing antioxidant extracts from an underutilized skeletal muscle source, mechanically separated pork (MSP), was investigated. Carnosine-containing MSP extracts were capable of inhibiting lipid oxidation both in vitro and in salted ground pork. Heating (60-80°C) the MSP extract removed iron and increased in vitro antioxidant activity. Isolation of a low molecular weight fraction of the MSP extract by ultrafiltration was effective at decreasing iron but did not substantially increase in vitro antioxidant activity. Freeze dried extracts (untreated, 80°C, ultrafiltration permeate) were capable of inhibiting both TBARS and lipid peroxide formation in ground, salted pork stored at -15°C. While MSP extracts were capable of inhibiting lipid oxidation both in vitro and in salted, ground pork, their antioxidant activity was low suggesting that their use as a food additive would be impractical.