On food and cooking the science and lore of the kitchen ( PDFDrive ) 1194

the consistency is very thick, almost
semisolid. Stirred into a thinner liquid, these
reduced creams have enough fat globules to
fill it and lend a substantial body. Cream
reduction and thickening can also be done at
thelastminute,forexampleafterasautépan
hasbeendeglazed;thecookaddscreamtothe
deglazingliquidandboilsthemixtureuntilit
reachesthedesiredconsistency.
Crème Frche in Sauce Making Reduced
creamshaveseveraldisadvantages.Theytake
time and attention to prepare, develop a
cooked flavor, and are very rich, sometimes
overly so for the balance of a given sauce.A
usefulalternativetoreducedcreamsiscrème
frche, a version of heavy cream whose
consistencyhasbeenthickenednotbyboiling
down, but by fermentation (p. 49). The acid
produced by lactic bacteria causes the casein
proteinsinthewaterphasetoclustertogether
and form a network that immobilizes the


water. Some strains of bacteria also secrete
long carbohydrate molecules that further
thickenthewaterphaseandactasstabilizers.
Usedinplaceofreducedcream,crèmefrche
requiresnopreparation,islessrich,andhasa
fresher flavor. Thanks to its low protein
content, it tolerates temperatures that would
curdlesourcream.

ButterLikeitsparentmaterial,cream,butter
is an emulsion: but it’s one of the few food
emulsions in which the continuous phase is
fat, not water. In fact, butter is made by
“inverting” the fat-in-water cream emulsion
to produce a water-in-fat emulsion (p. 33).
The continuous fat phase of butter, together
with some intact fat globules that survived
churning, takes up about 80% of its volume,
and the dispersed water droplets about 15%.
Whenitmelts,theheavierwaterdropletssink
to the bottom and form a separate layer. The
consistency of melted butter, then, is the