Comparison of hydrolysis characteristics on defatted peanut meal proteins between a protease extract from Aspergillus oryzae and commercial proteases

A crude protease extract (CPE) was prepared from Aspergillus oryzae HN 3.042 in this work. Three commercial proteases (Alcalase 2.4L, Protamex and papain) and CPE were employed to hydrolyse defatted peanut meal (DPM). CPE was found to be the most effective protease with protein recovery of 80.6%. Moreover, CPE produced a higher degree of hydrolysis (DH, 43.4%) than the tested commercial proteases. The test of molecular weight distribution indicated that DPM proteins were mainly consisted of >10 KDa fraction (86.6%), whereas 3–6 KDa fraction was observed to be the main fraction of all the hydrolysates. CPE hydrolysate possessed a higher nutritional quality than DPM and other hydrolysates on the basis of FAO/WHO (1991) reference pattern. The sensory taste evaluation showed that CPE hydrolysate had better taste than other hydrolysates.