Aggregation and gelation of micellar casein particles.
Micellar casein particles (submicelles) are formed by removing calcium phosphate from native casein. The submicelles aggregate and eventually form a gel with a rate that increases strongly with increasing temperature and casein concentration. At low casein concentrations the gel is very weak and collapses under its own weight so that a precipitate is formed. The structure of the aggregates is studied using light scattering and cryo-electron microscopy. It is found that the aggregates have a self-similar structure with fractal dimension 2. The viscoelastic properties of the gel are studied by frequency scans of the loss and storage moduli during the gelation process. The bonds between the submicelles probably involve calcium phosphate complexes.
Panouillé
Maud
M
Polymères, Colloïdes, Interfaces, UMR-CNRS, Université du Maine, 72085 Le Mans cedex 9, France.
Durand
Dominique
D
Nicolai
Taco
T
Larquet
Eric
E
Boisset
Nicolas
N
D002130:Calcium Phosphates / Q000737:chemistry; D002364:Caseins / Q000737:chemistry*; D020285:Cryoelectron Microscopy; D011756:Diphosphates / Q000737:chemistry; D005782:Gels / Q000737:chemistry; D008027:Light; D008823:Micelles; D046912:Multiprotein Complexes / Q000737:chemistry / Q000648:ultrastructure; D010316:Particle Size; D012212:Rheology; D012542:Scattering, Radiation; D014783:Viscosity
D002130:Calcium Phosphates; D002364:Caseins; D011756:Diphosphates; D005782:Gels; D008823:Micelles; D046912:Multiprotein Complexes; C020243:calcium phosphate; C003319:sodium pyrophosphate