Casein micelles possess a relatively large and rather
complex structure (diameter 20}600 nm) (Schmidt, 1982).
This colloidal assembly is a supramolecular association
of individual casein subunits: a41- , a42- , b- and i-caseins.
These fractions are organized within the micelle according
to their hydrophobic and hydrophilic groups, yielding
submicelles; i-casein is thought to be mainly present
on the surface of the micelle, providing a sterically
stabilizing outer layer (Visser, 1992). The submicelles are
held together by colloidal calcium phosphate (Van Dijk,
1990)