Probing the internal and external micelle structures of differently sized casein micelles from individual cows milk by dynamic light and small-angle X-ray scattering

Abstract

Casein micelles vary in size both within and between individual cows depending on the ratios of specific caseins and the level of glycosylation. In this work, milks were obtained from individual cows with known genetic variants of κ- and β-casein, and β-lactoglobulin, containing a range of native micelle diameters. κ- and β-Casein variants are known to influence rennetability of milk. The specific reason for these differences are not known, although, it is clear casein phenotype has an influence. Large and small micelle fractions were also prepared, narrowing the size distribution of micelles at both extremes. When examined by SAXS, all the milk samples were found to have identical scatterin..