Abstract: The invention relates to methods for providing compounds having an antihypertensive effect. More in particular, the invention relates to ACE (angiotensin I-converting enzyme)-inhibitory peptides that can be released enzymatically from whey proteins. Provided is a method for providing a protein hydrolysate having ACE-inhibitory activity, comprising treating a whey protein-containing substrate with a bacterial heat-labile neutral protease to produce a primary hydrolysate and treating said primary hydrolysate with a thermolysin to produce a secondary hydrolysate. Also provided are hydrolysates and isolated peptides obtainable by said method and uses thereof for the preparation of a medicament for inhibiting ACE activity in a mammal; for lowering the blood pressure; and/or for preventing the occurrence of hypertension.