ABSTRACT
The effects of proteolytic enzyme type (including pancreatin and proteases from
Bacillus licheniformis, Aspergillus oryzae and A. sojae) and enzyme : substrate ratio
(E : S = 0.5:100, 1:100, 2:100, 3:100, 4:100 and 8:100) were evaluated in this work
with the aim of obtaining whey protein concentrate hydrolysates with inhibitory
activity toward angiotensin-converting enzyme. Twenty-four hydrolysates were
prepared, and their inhibitory activities (IA) were evaluated in vitro, resulting in
inhibition rates ranging from 2.02 to 96.66%. Eleven samples had IAs that were
very high (>80%). The hydrolysates obtained using the B. licheniformis protease
had the highest IA values at all tested E : S ratios. In some cases, lowering the E : S
ratio produced a higher IA value. This was observed for the B. licheniformis protease
when the ratio was lowered from 2:100 to 1:100, as well as for the A. oryzae
protease when lowered from 3:100 to 2:100 and from 2:100 to 1:100.