On Food and Cooking

whose powerful aroma contributes to the
characteristic flavor of cooked milk (and
many other animal foods).
In boiling milk, unfolded lactoglobulin
binds not to itself but to the capping-casein on
the casein micelles, which remain separate; so
denatured lactoglobulin doesn’t coagulate.
When denatured in acid conditions with
relatively little casein around, as in cheese
whey, lactoglobulin molecules do bind to each
other and coagulate into little clots, which can
be made into whey cheeses like true ricotta.
Heat-denatured whey proteins are better than
their native forms at stabilizing air bubbles in
milk foams and ice crystals in ice creams; this
is why milks and creams are usually cooked
for these preparations (pp. 26, 43).