Effect of pretreatment on enzymatic hydrolysis of bovine collagen and formation of ACE-inhibitory peptides

•Alcalase and collagenase degraded collagen type I completely, other enzymes only to some extent.•Pretreatment by boiling for 5min improved the hydrolysis with most enzymes.•A high pressure treatment at 600MPa improved hydrolysis and ACE-inhibition with Alcalase and collagenase.•Alcalase hydrolysates showed the highest DH and ACE-inhibition.•New potential ACE-inhibitory peptides released by Alcalase were identified.