Antioxidant and angiotensin-I converting enzyme inhibitory activity in the water-soluble protein extract from Petrovac Sausage (Petrovská Kolbása)

Petrovac Sausage (Petrovská Kolbása) is a traditional dry fermented sausage from Bački Petrovac (province Vojvodina, Serbia). In this study, the in vitro antioxidant and angiotensin-I converting enzyme (ACE) inhibitory activities in the water-soluble (pH 7.4) protein extracts were evaluated throughout the sausage ripening. In the protein extract from the sausage mixture (day 0) degree of hydrolysis (DH) of 6.07 ± 0.84% was determined, which reached 17.71 ± 0.76% after 90 days. The protein extract at day 0 showed free radical (2.2-diphenyl-1-picrylhydrazyl, DPPH ) scavenging assay (RSA) and reducing power (RP) of 27.61 ± 0.73% and 0.493 ± 0.016, respectively. In fermented sausage at day 90, RSA and RP increased up to 50.08 ± 1.25% and 0.972 ± 0.065%, respectively. The examined protein extracts exhibited ACE inhibitory activity, which also enhanced; from 27.11 ± 2.163% (day 0) to 73.74 ± 3.299% (day 90). These results suggested that in Petrovská Kolbása, the final products of meat proteins hydrolysis during sausage ripening might be hydrolysates with antioxidant and ACE inhibitory properties.