distinguishing characteristic is the content and
quality of gluten proteins, with high protein
content and strong gluten often coinciding
with a hard, glassy, translucent grain interior.
Hard wheat grains constitute about 75% of the
American crop. Soft wheats, which make up
20% of the crop, have a lower amount of
somewhat weaker gluten proteins. Club wheat
is a distinct species, T. compactum, whose
proteins form an especially weak gluten.
Durum wheat is another distinct species (T.
turgidum durum, p. 465) used mainly to make
pasta (p. 571).
A close-up view of bread dough. The dense
mass of gluten and starch is divided and
tenderized by gas bubbles. starch granules