RESUMEN

Protein hydrolysates were prepared from chicken liver using fermentation and enzymatic hydrolysis. The lactic acid bacteria Pediococcus acidilactici NCIM5368 was employed in the fermentation process and a commercial protease (Alcalase® 2.5) was used in enzymatic hydrolysis. Chicken liver hydrolysates prepared by fermentation (FCLH) and enzymatic hydrolysis (ECLH) revealed appreciable amounts of protein [55.85 and 61.34 %; on dry weight basis, respectively]. Fermentation and enzymatic hydrolysis resulted in 14.3 and 26.12 % of degree of hydrolysis. Total antioxidant activity, reducing power, scavenging of superoxide, 2- diphenyl-1-picrylhydrazyl (DPPH) and 2, 2-azino-bis-3-ethyl-benzthiazoline-6-sulphonic acid (ABTS) radicals were determined for both FCLH & ECLH. FCLH & ECLH showed total antioxidant activity of 0.99 and 1.13 µg AAE mg(-1) proteins, respectively; while, they scavenged 96.14 and 92.76 % of DPPH radicals respectively. FCLH showed higher ABTS radical scavenging activity (32.16 %) than ECLH (19.29 %). Superoxide anion scavenging activity of FCLH & ECLH were found to be 95.02 & 88.94 %, respectively. Residues obtained after both treatments also exhibited antioxidant activities. FCLH reported highest antagonistic activity against Listeria monocytogenes (30 mm); while, ECLH showed antibacterial activity only against Micrococcus luteus (12 mm). Both hydrolysates have the potential to be a protein rich ingredient for use in formulated foods and possible help in reduction of oxidative stress.