title: Effect of extraction pH on techno-functional properties of crude extracts from wild cardoon (Cynara cardunculus L.) flowers.
abstract: In the present paper, techno-functional properties of rennet derived from C. cardunculus, prepared at various pH (from 3 to 6), were investigated. It was found that the extract prepared at pH 3 had the best milk-clotting properties (MCA/PA ratio). It presented also the highest enzyme content, determined by densitometry analysis on 1D and 2D gels electrophoresis. Formation of milk gels produced by the extracts and chymosin was monitored using dynamic rheology and turbiscan. It can be assumed that by lowering rennet pH, milk pH decreases, causing a significant increase of curd firmness and both elastic (G') and viscous (G″) moduli. Results obtained by turbiscan showed similar ΔBS values of gels produced, after 2h, by chymosin and the crude extract at pH 3. In conclusion, C. cardunculus extract prepared at low pH has the potential to be employed as an efficient milk-clotting agent in the production of dairy products.
authors.affiliation: University of Liège, Gembloux Agro-Bio Tech, Unit of Food Science and Formulation, Passage des Déportés 2, Gembloux B-5030, Belgium; University of Sfax, National Engineering School of Sfax, Laboratory of Food Analysis, Soukra Road, BP W-3038 Sfax, Tunisia.
authors.forename: Amal
authors.initials: A
authors.lastname: Ben Amira
authors.affiliation: University of Sfax, National Engineering School of Sfax, Laboratory of Food Analysis, Soukra Road, BP W-3038 Sfax, Tunisia.
authors.forename: Ines
authors.initials: I
authors.lastname: Makhlouf
authors.affiliation: University of Liège, Gembloux Agro-Bio Tech, Unit of Food Science and Formulation, Passage des Déportés 2, Gembloux B-5030, Belgium.
authors.forename: Raul
authors.initials: R
authors.lastname: Flaviu Petrut
authors.affiliation: University of Liège, Gembloux Agro-Bio Tech, Unit of Functional and Evolutionary Entomology, Passage des Déportés 2, Gembloux B-5030, Belgium.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Francis
authors.affiliation: University of Liège, Gembloux Agro-Bio Tech, Unit of Functional and Evolutionary Entomology, Passage des Déportés 2, Gembloux B-5030, Belgium.
authors.forename: Julien
authors.initials: J
authors.lastname: Bauwens
authors.affiliation: University of Sfax, National Engineering School of Sfax, Laboratory of Food Analysis, Soukra Road, BP W-3038 Sfax, Tunisia.
authors.forename: Hamadi
authors.initials: H
authors.lastname: Attia
authors.affiliation: University of Sfax, National Engineering School of Sfax, Laboratory of Food Analysis, Soukra Road, BP W-3038 Sfax, Tunisia. Electronic address: besbes_souhail@yahoo.fr.
authors.forename: Souhail
authors.initials: S
authors.lastname: Besbes
authors.affiliation: University of Liège, Gembloux Agro-Bio Tech, Unit of Food Science and Formulation, Passage des Déportés 2, Gembloux B-5030, Belgium.
authors.forename: Christophe
authors.initials: C
authors.lastname: Blecker
mesh_terms: D000818:Animals; D002611:Cheese / Q000032:analysis*; D012085:Chymosin / Q000737:chemistry*; D031942:Cynara / Q000737:chemistry*; D035264:Flowers / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008892:Milk / Q000737:chemistry*
chemical_list: D012085:Chymosin
keywords: Crude extract; Extraction pH; Milk-clotting activity; Rheological properties; TURBISCAN; Wild cardoon