ACE inhibitor antihypertensive medications exert an antihypertensive effect by inhibiting angiotensin-converting enzyme (ACE), which catalyzes the production of the vasoconstrictor angiotensin II and inactivates the vasodilator bradykinin. While no benefit has been established and more research is needed, it has been reported that ACE-inhibiting peptides may be formed naturally through the fermentation of milk proteins by certain probiotics (Seppo et al., 2003). Two tripeptides, valine-proline-proline and isoleucine-proline-proline, have been identified as the active components in some fermented dairy products (Sanders ME, 2000). Several studies have been performed in spontaneously hypertensive rats using these bioactive ACE inhibitor peptides derived from fermented milk proteins (Fitzgerald RJ et al., 2004).