without curdling.
The Caseins The casein family includes four
different kinds of proteins that gather together
into microscopic family units called micelles.
Each casein micelle contains a few thousand
individual protein molecules, and measures
about a ten thousandth of a millimeter across,
about one-fiftieth the size of a fat globule.
Around a tenth of the volume of milk is taken
up by casein micelles. Much of the calcium in
milk is in the micelles, where it acts as a kind
of glue holding the protein molecules
together. One portion of calcium binds
individual protein molecules together into
small clusters of 15 to 25. Another portion
then helps pull several hundred of the clusters
together to form the micelle (which is also
held together by the water-avoiding
hydrophobic portions of the proteins bonding
to each other).
Keeping Micelles Separate... One member of