| Wheat
It is believed that wheat developed
from a type of wild grass native to the arid lands of Asia Minor. Cultivation of wheat is
thought to have originated in the Euphrates Valley as early as 10,000 B.C., making it one
of the world's oldest cereal crops. In the Mediterranean region, centuries before recorded
history, wheat was an important food. Wheat played such a dominant role in the Roman
Empire that at the time it often was referred to as a "Wheat Empire."
Wheat, which can be produced in a wide
range of climates and soil conditions, grows in areas as far north as the Arctic Circle
and as far south as the equator. The production of wheat is so widespread that it is being
harvested somewhere in the world in any given month. But wheat grows best in regions
having temperate climates with rainfall between 12 and 36 inches per year. The United
States ranks fourth in world wheat production, following: 1) China; 2) the Commonwealth of
Independent States; and 3) the European Community (whose major producers are France, the
United Kingdom and Germany).
The Varieties of Wheat
The number of wheat varieties exceeds
any other seed-bearing plant. There are two general types of wheat -- Winter and Spring --
reflecting the time of year the seed is planted.
The Wheat Plant -- Stages of Life
The stages of life of the wheat plant
vary somewhat depending upon the variety being grown:
- Planting: Planting of winter wheat
usually occurs in September or early October when the soil has sufficient moisture to
germinate the seed. The germinated seed lies dormant during the winter. Spring wheat
is planted as early in the spring as temperatures allow.
- Growing: The winter wheat plant resumes
its growth in the spring. The head of the wheat plant, which contains the kernels,
develops at the tip of the stem. The stem grows rapidly, pushing the head up and out of
the top leaf sheath. After the head emerges, flowering occurs and the kernels begin to
develop. After the kernels have developed fully and filled, the leaves and stem lose their
green color and the kernels quickly dry.
- Harvest: Combines harvest the crop once the
kernels have dried to 15 percent moisture or less. Harvesting of winter wheat
starts in May and usually is completed by late July. Harvesting of spring wheat
begins in late July and is completed by late August.
Wheat -- How It's
Transformed into Useful Products
Before it can be used as food or feed,
wheat must be processed by a mill. Flour millers select wheat based upon its protein
content, price, baking quality, appearance, flour yield value and other quality factors.
There are four major steps in the flour milling process:
- Cleaning: First, the wheat is cleaned by
specially designed machines that remove impurities, such as garlic bulblets, weed seeds
and straw.
- Tempering: Moisture then is applied to the
kernel in a process known as tempering, which toughens the bran coat and causes it to
separate more completely from the endosperm.
- Grinding: The tempered wheat then is fed to the
mill, where the kernel is cracked and ground by passing it through a series of rollers.
After each set of rollers, the wheat is sifted to separate the fine flour particles from
the coarser endosperm particles and bran. The fine particles become the flour. The
intermediate products, with a texture between bran and flour, are known as the middlings.
Middlings are removed and used in livestock feed.
- Enrichment: In the final step, the miller
bleaches the flour and adds B vitamins (such as niacin, thiamine and riboflavin), as well
as iron, to the flour before it is packaged.
Wheat -- Different Classes for Different Uses
Hard wheats contain more protein (11
to 18 percent) than soft wheats (8 to 11 percent). Hard wheats also contain more gluten.
These different quality factors make each class of wheat desirable for specific -- but
different -- foods:
- Hard Red Winter Wheat and Hard Red Spring Wheat
produce a high-grade flour used to make bread, hamburger buns and biscuits.
- Soft wheat produces a flour that is desirable
for baked goods that have a tender, flaky or crisp texture, like cakes, doughnuts, cookies
and crackers.
- White wheat is a soft wheat that produces flour
used for cereals, cookies and cakes
- Durum -- which contains more protein than any
other class -- produces a coarse, golden amber product called semolina that is mixed with
water to form a dough that then is forced through dies that shape it into pasta products
like spaghetti, noodles and macaroni.
Wheat is very
important food
Wheat is the dominant grain of world commerce. It is easily
transported and stored and it is used to produce a large variety of foods that include
many kinds and types of breads, cakes, noodles, crackers, breakfast foods, biscuits,
cookies, and confectionary items.
Wheat is the staple
food of millions of people. It is also an important part of the daily diet of many
millions more. Only rice challenges wheat for the title of most important food grain in
the world.
The world wheat market
is enormous. Annual global wheat consumption is in excess of 550 million tonnes (20
billion bushels). Farmers of the world produce almost 20 times as much wheat as is
produced in Canada to satisfy this growing appetite.
Approximately
two-thirds of the wheat produced in the world is used for human food and about one-sixth
is used for livestock feed. Industrial uses, seed requirements, and post-harvest losses
account for the remaining withdrawals from the world wheat granaries.
World wheat production
increased at a rate of 3.3 percent per year between 1949 and 1978 .Increases at the start
of this period were due to both an expansion of production area and increased per acre
yields. However, starting in the 1960's, increased yields from improved varieties and a
greatly expanded use of irrigation, pesticides, and fertilizers took on greater importance
in sustaining the high rate of growth in world wheat production. In fact, the impact of
new production technologies was so significant that their widespread adoption during this
period became known as the "green revolution".
Wheat production
trends shifted dramatically in the 1980's . Rate of increase in world wheat production
slowed to 1.5 percent per year between 1982 and 1991. China maintained its rate of
increase in production at 2.6 percent per year and became the world's largest wheat
producer (Figure 2). Wheat production in India and Pakistan also increased at nearly 3
percent per year during this period. Smaller wheat producing countries in the
"others" category increased production by 2.8 percent per year and accounted for
a significant 16 percent of world wheat supply. Wheat production in Russia was very
erratic during this period and its contribution to total world production fell to 16
percent. There are many factors that influence the pattern of wheat consumption in the
world. The most important of these include: Price, Supply, Consumer income, Availability
of substitutes, and Politics.
Market opportunities
are influenced by a country's stage of economic development. Therefore, wheat consumption
should not be looked upon as a constant for any particular region or country. In a free
market environment, increases in income of the poorest consumers generally results in a
greater consumption of wheat for food. As consumer income increases wheat is gradually
replaced by more expensive foods, particularly meat. As a result, wheat consumption in
more affluent countries often depends upon its use for both human food and livestock feed.
The basics of
wheat economics.
When supplies of a
commodity are excessive, prices decline. When demand for the commodity increases, so does
the price. Typically, companies invest from 5% to 7% of their gross revenues to
product promotion.
Individually, wheat
farmers have little impact on demand, but putting all the heads together can make a
significant difference in product demand and market price. And that leads to the ultimate
goal of the improved income for wheat producers.
Wheat
Products
Bread is a major
commodity in the world. Millions of loaves are produced in automated bakeries every day.
The more automated a process becomes, the less chance people operating the bakery have to
make changes for variations in wheat flour properties.: The three components known to
affect the baking quality of wheat flour: are starch, proteins, and lipids. Scientists in
this unit analyze these components. The first step in understanding these roles is to be
able to accurately and quickly measure the amounts, sizes and types of each fraction.
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