Agriculture Reference
In-Depth Information
wheat”—the hexaploid species,
Triticum aesti-
vum
. Even for this common product, there is a
wide range of types, depending on whether
wholemeal or white fl our has been the raw mate-
rial, depending on the shape and size of the loaf,
and depending on the range of possible addi-
tives such as rye fl our, milk solids, and whole or
kibbled (coarsely ground) grains (Khan and
Shewry 2009). In addition, different methods of
production may have led to the fi nal product
presented to the customer. For example, the
multiple sheeting method may have been used
to develop the dough instead of conventional
mixing, and even the latter may have involved
the application of pressure to improve crumb
structure. Specialty breads include products
for special diets, such as gluten-free, yeast-free,
and milk-free. The western diet also includes
a wide range of pastries, cakes, and cookies
(biscuits). Wheat fl our is the main raw material
for many food products such as soups, por-
ridge, breakfast cereals, confectionary, sausages,
thickening agents, condiments, custards, and
sauces.
Animal feed constitutes a signifi cant use of
wheat (about 15% globally). In this case,
wheat may make an important (low-cost) con-
tribution to energy needs, while various
other ingredients are included for other pur-
poses, such as complementing the low lysine
content of wheat. Grains may be fed as the whole
grain, as partly milled, or in pellet form.
This use of wheat is especially cost-sensitive,
so the lower grades of wheat usually contribute
to feed uses.
The pasta family of foods adds a further
dimension of variety in its many forms—maca-
roni, spaghetti, and vermicelli (Fabriana and
Lintas 1988). Durum wheat is the preferred raw
material for pasta, and also for couscous and
burghul (also known as bulgar, bulgur, or bulghur)
(Bayram 2007). Pasta should not be confused with
noodles, in their many forms, which are made
from bread wheat. Durum is a species distinct
from hexaploid bread wheat, being tetraploid of
the species
T. durum
, also designated
T. turgidum
var.
durum
.
The range of uses of wheat—”exotic”
foods
A much wider range of wheat-based foods exists
beyond the traditional “western” range, but these,
previously labeled as exotic, have in recent decades
become familiar around the world (Faridi and
Faubion 1995). These include foods traditional in
Asian and Middle Eastern countries—noodles, in
their many forms, fl at breads (pocket, Arabic,
chapatti), and Chinese steamed breads. Some of
these are listed in Table 21.1 and illustrated in
Color Plate 35.
Industrial uses of wheat
Signifi cant amounts of wheat fl our are used for
separating starch from gluten (fi nal product listed
in Table 21.1). Much of the resulting “vital wheat
gluten” is used to fortify the dough strength of
fl our for breadmaking and for special snack foods.
Being a low-priced food protein, gluten has also
found many food uses where protein supplemen-
tation is needed, for example, in meat and cheese
products. This supplementation, in the form of
vital dry gluten, may make use of the unique
rheological properties of gluten, or in other cases
denatured gluten is used when these properties
are not appropriate.
Gluten also provides its unique functional
properties to special animal feeds, especially for
pet foods as a calf-milk substitute and for aqua-
culture (Day et al., 2006). Gluten-based packag-
ing fi lms and coatings are favored as edible and
biodegradable air barriers. After modifi cation by
acidic or enzymatic hydrolysis, gluten may serve
ingredient uses for emulsifying and foaming in
foods. The many nonfood applications of gluten
include grafting into resins and polymers, mois-
turizing in cosmetics, and foaming in hair-care
products.
The starch from gluten washing fi nds many
nonfood uses, especially for paper manufacture,
and even for mineral refi ning. For home cooking
use, wheat starch may fi nd its way into the super-
market labeled as corn fl our, although not
derived from corn or maize (
Zea mays
L.). It is an
