Comparative studies on the gelling properties of cardosins extracted from Cynar...

• Author(s): Silva, Sofia V. ; Allmere, Toomas ; Malcata, F. Xavier ; Anders; A.
• Date: 2003
• Persistent ID: http://hdl.handle.net/10400.14/3582
• Origin: Veritati - Repositório Institucional da Universidade Católica Portuguesa
• Subject(s): Proteases; Cheesemaking; Rheology; Dairy products; Coagulation
• Document Type: Article
• Language: English

Description

A comparative study was developed on the clottingactivities and gelling properties of cardosins A and B, extracted from dried flowers of Cynara cardunculus, and chymosin on cow’s skim milk, at various pH values. The determination of the total milk-clotting activity was performed followingan international standard, whereas a rheometer was employed to measure the viscoelastic properties of the gels subsequently formed: the evolution of the complex modulus (G ) and the phase angle (d) was monitored with time. The G values of the milk gels were higher for cardosins than for chymosin at pH 6.6, but the reverse held at pH 6.4 and 6.2. The d values were identical for all three enzymes tested. Chymosin exhibited the highest specific milk clotting activity, followed by cardosin B. The clottingactivity of chymosin seems to be more influenced than that of cardosins by the pH of milk.