starch chains are modified in this way, and so
the more roux is required to create a given
thickness. It takes more of a dark brown roux
than a light one to thicken a given amount of
liquid. (The industrial version of roux making
to make a starch more dispersable and stable
to cooling is called dextrinization, and
involves heating dry starch together with
some dilute acid or alkali to 375ºF/190ºC.)
Outside of France, roux are especially
prominent in the cooking of New Orleans,
where flour is cooked to a number of different
stages from pale to chocolate-brown, and
where cooks may use several roux in a single
gumbo or stew to lend their distinct layers of
flavor.
Starch in Classic French Sauces
In the code formalized by Auguste Escoffier
in 1902, there are three leading mother sauces
that are thickened in part with flour: the