Small-angle neutron scattering, casein

Thurn, A., Burchard, W., Niki, R. (1987a). Structure of casein micelles. I. Small-angle neutron scattering and light scattering from p- and K-casein. Colloid and Polymer Science, 265, 653-666. 

Holt, C., de Kruif C.G., Tuinier, R., Timmins, P.A. (2003). Substructure of bovine casein micelles by small-angle X-ray and neutron scattering. Colloids and Surfaces A Physicochemical and Engineering Aspects, 213, 275-284. 

Nevertheless, much is known about the structure of adsorbed 6-casein, certainly more flian is known for any other food protein, and various techniques have been used to study the adsorbed protein. The first evidence from DLS showed that 6-casein adsorbed to a polystyrene latex caused an increase in the radius of the particle by 10 to 15 nm (84). Later studies using small-angle X-ray scattering confirmed this and showed, in addition, that the bulk of the mass of the protein was close to the interface, so the interfacial layer was not of uniform density throughout (85). Neutron-reflectance studies also showed that most of the mass of protein was close to the interface (86). Only a relatively small portion of the mass of the adsorbed protein extends from the tightly packed interface into the solution, but it is this part which determines the hydrodynamics of the particle and which is almost certainly the soiuce of the steric stabilization which the 6-casein affords to emulsion droplets (84). It is to be noted that all of the studies just described were performed on latex particles or on planar interfaces however, it has also been demonstrated that the inter-facial structiues of 6-casein adsorbed to emulsion dro plets resemble those of the model particles (39, 85). Although detailed control of emulsion droplets dining their... 

Information about the adsorbed layer strueture of P-casein at the hydrophobic surface can be obtained by employing neutron refleetivity, small-angle X-ray scattering (SAXS), and dynamic light scattering. It was found that the layer of P-casein adsorbed to a hydrocarbon oil/water interface or an air/water interface (70, 71) consisted of a dense inner part, 2 nm thick, and a protein volume fraction of 0.96, immediately adjacent to the interface. Beyond that a second dilute region with a protein volume fraction of 0.15 extended into the aqueous phase. A similar structure of P-casein adsorbed on to polystyrene latex particles was observed with SAXS (65). The electron-density profile cal-... 

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