Angiotensin converting enzyme (ACE) inhibitory and antihypertensive activities of protein hydrolysate from meat of Kacang goat (Capra aegagrus hircus)

BACKGROUND The meat of Kacang goat has potential for production of a protein hydrolysate. Functional ingredients from protein hydrolysate of Kacang goat meat were determined by the consistency of angiotensin‐converting enzyme (ACE) inhibitory activity and antihypertensive effect. This study examined the potency of Kacang goat protein hydrolysate in ACE inhibition and antihypertensive activity. RESULT Protein hydrolysates of Kacang goat meat were prepared using sequential digestion of endo‐proteinase and protease complex at several concentrations and hydrolysis times. The highest ACE inhibitory activity resulted from a hydrolysate that was digested for 4 h with 5 g kg−1 of both enzymes. An ACE inhibitory peptide was purified and a novel peptide found with a sequence of Phe‐Gln‐Pro‐Ser (IC50 value of 27.0 µmol L−1). Both protein hydrolysates and a synthesised peptide (Phe‐Gln‐Pro‐Ser) demonstrated potent antihypertensive activities in spontaneously hypertensive rats. CONCLUSION Protein hydrolysate of Kacang goat meat produced by sequential digestion with endo‐proteinase and protease complex has great potential as a functional ingredient, particularly as an antihypertensive agent. © 2015 Society of Chemical Industry