Tavares, T. G.Contreras, M. M.Amorim, M.Martín-Álvarez, P. J.Pintado, M. E.Recio, I.Malcata, F. X.2012-02-272012-02-272011TAVARES, T. G... [et al.] - Optimisation, by response surface methodology, of degree of hydrolysis and antioxidant and ACE-inhibitory activities of whey protein hydrolysates obtained with cardoon extract. International Dairy Journal. ISSN 0958-6946. Vol. 21, n.º 12 (2011), p. 926-9330958-6946http://hdl.handle.net/10400.14/7964The hydrolysis of bovine whey protein concentrate (WPC), alpha-lactalbumin (alpha-La) and caseinomacropeptide (CMP), by aqueous extracts of Cynara cardunculus, was optimized using response surface methodology. Degree of hydrolysis (DH), angiotensin-converting enzyme (ACE)-inhibitory activity and antioxidant activity were used as objective functions, and hydrolysis time and enzyme/substrate ratio as manipulated parameters. The model was statistically appropriate to describe ACE-inhibitory activity of hydrolysates from WPC and alpha-La, but not from CMP. Maximum DH was 18% and 9%, for WPC and alpha-La, respectively. 50% ACE-inhibition was produced by 105.4 (total fraction) and 25.6 mu g mL(-1) (<3 kDa fraction) for WPC, and 47.6 (total fraction) and 22.5 mu g mL(-1) (<3 kDa fraction) for alpha-La. Major peptides of fractions exhibiting ACE-inhibition were sequenced. The antioxidant activities of WPC and alpha-La were 0.96 +/- 0.08 and 1.12 +/- 0.13 mmol trolox equivalent per mg hydrolysed protein, respectively.engjournal article10.1016/j.idairyj.2011.05.0131879-014380052907959000295830900004