while making it somewhat harder for the
thickener proteins to bond to each other and
coagulate. The inclusion of flour or starch can
protect sauce proteins from coagulating; the
long starch molecules get in the way of the
proteins and prevent them from forming many
strong bonds with each other.
If you do overcook a protein-thickened
sauce and it separates into thin liquid and
grainy particles, you can salvage it by
remixing the sauce in a blender, straining it of
any remaining coarse particles, and if
necessary rethickening it with whatever
materials are handy (egg yolks, flour, or
starch).
Egg Yolks Egg yolks are the most efficient
protein thickeners, in part because they are so
concentrated: egg yolks are only 50% water
and 16% protein. They are also the handiest,
being a common, inexpensive ingredient, and
their proteins are already finely dispersed in a