title: Inhibition and Promotion of Heat-Induced Gelation of Whey Proteins in the Presence of Calcium by Addition of Sodium Caseinate.
abstract: Heat-induced aggregation and gelation of aqueous solutions of whey protein isolate (WPI) in the presence of sodium caseinate (SC) and CaCl2was studied at pH 6.6. The effect of adding SC (0-100 g/L) on the structure of the aggregates and the gels was investigated by light scattering and confocal laser scanning microscopy at different CaCl2concentration ([CaCl2] = 0-30 mM). The gelation process was studied by oscillatory shear rheology. At the whey protein concentrations studied here (34 and 60 g/L), no gels were formed in the absence of CaCl2and SC. However, WPI solutions gelled above a critical CaCl2concentration that increased with increasing SC concentration. In the absence of CaCl2, WPI gels were formed only above a critical SC concentration. The critical SC concentration needed to induce WPI gelation decreased weakly when CaCl2was added. In an intermediate range of CaCl2concentrations, gels were formed both at low and high SC concentrations, but not at intermediate SC concentrations. Finally, at high CaCl2concentrations gels were formed at all SC concentrations. The gelation rate and the gel structure of the gels formed at low and high casein concentrations were very different. The effect of SC on the thermal gelation of WPI was interpreted by competition for Ca2+, a chaperon effect, and microphase separation.
authors.affiliation: IMMM, Université du Maine, IMMM UMR-CNRS , 72085 Le Mans Cedex 9, France.
authors.forename: Bach T
authors.initials: BT
authors.lastname: Nguyen
authors.affiliation: IMMM, Université du Maine, IMMM UMR-CNRS , 72085 Le Mans Cedex 9, France.
authors.forename: Gireeshkumar
authors.initials: G
authors.lastname: Balakrishnan
authors.affiliation: IMMM, Université du Maine, IMMM UMR-CNRS , 72085 Le Mans Cedex 9, France.
authors.forename: Boris
authors.initials: B
authors.lastname: Jacquette
authors.affiliation: IMMM, Université du Maine, IMMM UMR-CNRS , 72085 Le Mans Cedex 9, France.
authors.forename: Taco
authors.initials: T
authors.lastname: Nicolai
authors.affiliation: IMMM, Université du Maine, IMMM UMR-CNRS , 72085 Le Mans Cedex 9, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Chassenieux
authors.affiliation: Food Science and Technology Department, Nestec Ltd, Nestlé Research Center , P.O. Box 44, CH-1000 Lausanne 26, Switzerland.
authors.forename: Christophe
authors.initials: C
authors.lastname: Schmitt
authors.affiliation: Food Science and Technology Department, Nestec Ltd, Nestlé Research Center , P.O. Box 44, CH-1000 Lausanne 26, Switzerland.
authors.forename: Lionel
authors.initials: L
authors.lastname: Bovetto
mesh_terms: D002118:Calcium / Q000737:chemistry*; D002364:Caseins / Q000737:chemistry / Q000494:pharmacology; D005782:Gels / Q000737:chemistry; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D012212:Rheology; D012996:Solutions / Q000737:chemistry; D000067816:Whey Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry*
chemical_list: D002364:Caseins; D005782:Gels; D012996:Solutions; D000067816:Whey Proteins; D002118:Calcium