Simulation of the shape and size of casein micelles in a film state

Ronald Gebhardt, Ulrich Kulozik

Research output: Contribution to journalArticlepeer-review

13 Scopus citations

Abstract

Size fractionated casein micelles (CMs) form homogeneous films in which they are densely packed. The lateral size of CMs in films can be well resolved by surface-sensitive methods, but the estimation of their heights is still a challenge. We show that height information can be obtained from scattering patterns of GISAXS experiments on highly ordered casein films. We use an elastic scattering approach within the distorted wave Born approximation (DWBA) to simulate for the first time the two-dimensional intensity distribution of a GISAXS experiment of the CM near their critical angle. The model which fits the GISAXS data best considers an ellipsoidal form factor for the CM and an arrangement on a hexagonal lattice. Our results indicate that during film formation the spherical solution structure of CMs becomes compressed in the direction perpendicular to the film surface. In the film state, the micelles assume an oblate ellipsoidal shape with an aspect ratio of 1.9. Hence, their surface and contact area to the surrounding increases. As a result, the density of κ-casein on the micellar surface decreases, which could influence the functional properties of coatings and films. This journal is

Original languageEnglish
Pages (from-to)780-785
Number of pages6
JournalFood and Function
Volume5
Issue number4
DOIs
StatePublished - Apr 2014

Fingerprint

Dive into the research topics of 'Simulation of the shape and size of casein micelles in a film state'. Together they form a unique fingerprint.

Cite this