On Food and Cooking

to find a replacement that closely
approximates the original. The box on p. 530
lists the compositions of common wheat
flours.
Whole wheat flours are high in protein, but
a significant fraction of that protein comes
from the germ and aleurone layer and does not
form gluten; and germ and bran particles
interfere with gluten formation. They
therefore tend to make dense but flavorful
breads. Bread flours are high in strong gluten
proteins, and give the lightest, highest, and
chewiest loaf breads. Both pastry and cake
flours have low levels of weak gluten protein
for making tender baked goods. Cake flour is
distinctive because it’s treated with chlorine
dioxide or chlorine gas. This treatment has
several effects on the starch granules that are
useful in cake making (p. 555), and leaves a
trace of hydrochloric acid in the flour, which
gives batters and doughs an acid pH and
slightly acid taste.