Cereal
From Wikipedia, the free encyclopedia
Cereal is a grass (members of the monocot
family Poaceae, also known as Gramineae)[1]
cultivated for the edible components of their grain
(botanically, a type of fruit called a caryopsis),
composed of the endosperm, germ, and bran. Cereal grains are grown in greater quantities and provide
more food energy worldwide than any other type of crop[citation needed]; they are therefore staple crops.
In their natural form (as in whole grain),
they are a rich source of vitamins, minerals, carbohydrates, fats, oils, and protein.
However, when refined by the removal of the bran and germ,
the remaining endosperm is mostly carbohydrate
and lacks the majority of the other nutrients. In some developing nations, grain in the form of rice, wheat, millet, or maize constitutes a majority of daily
sustenance. In developed nations, cereal consumption is moderate and varied but still
substantial.
History
The first cereal grains were domesticated
about 12,000 years ago by ancient farming communities in the Fertile Crescent region. Emmer wheat, einkorn wheat, and barley were three of the so-called Neolithic founder crops in the development of agriculture.
The name comes from the word "Ceres", the Roman goddess of the
harvest.
Production
The following table shows annual
production of cereals, in 1961,[2]
2008, 2009, and 2010 ranked by 2010 production.[3]
All but buckwheat and quinoa are true grasses (these two are pseudocereals).
Grain
|
Notes
|
||||
2010
|
2009
|
2008
|
1961
|
||
Maize
(corn)
|
844
|
820
|
827
|
205
|
A staple food of people in
America, Africa, and of livestock
worldwide; often called corn or Indian corn in North America, Australia, New
Zealand, and Japan. A large portion of maize crops are grown for purposes
other than human consumption.
|
672
|
685
|
689
|
285
|
||
651
|
687
|
683
|
222
|
The primary cereal of temperate
regions. It has a worldwide consumption but it is a staple food of North
America, Europe, Australia and New Zealand.
|
|
123
|
152
|
155
|
72
|
||
56
|
56
|
66
|
41
|
Important staple food in Asia and
Africa and popular worldwide for livestock
|
|
29
|
27
|
35
|
26
|
A group of similar but distinct
cereals that form an important staple food in Asia and Africa.
|
|
20
|
23
|
26
|
50
|
Formerly the staple food of
Scotland and popular worldwide as a winter breakfast food and livestock feed
|
|
13
|
16
|
14
|
12
|
||
12
|
18
|
18
|
35
|
Important in cold climates
|
|
1.5
|
1.8
|
2.2
|
2.5
|
A pseudocereal, as it is a Polygonaceae
and not a Poaceae or Gramineae, used in Eurasia.
Major uses include various pancake and groats
|
|
0.53
|
0.46
|
0.50
|
0.18
|
Several varieties of which are
grown as food crops in Africa
|
|
0.07
|
0.07
|
0.06
|
0.03
|
Maize, wheat and rice together
accounted for 87% of all grain production worldwide, and 43% of all food
calories in 2003,[3]
while the production of oats and rye have drastically fallen from their 1960s
levels. Other grains that are important in some places, but that have little
production globally (and are not included in FAO statistics), include:
- Teff,
popular in Ethiopia but scarcely known elsewhere. This ancient grain is a
staple in Ethiopia. It is high in fiber and protein. Its flour is often
used to make injera. It can also be eaten as a warm breakfast cereal
similar to farina with a chocolate or nutty flavor. Its flour and whole
grain products can usually be found in natural foods stores.
- Wild rice,
grown in small amounts in North America
- Amaranth,
ancient pseudocereal, formerly a staple crop of the Aztec Empire and now widely grown in Africa
- Kañiwa,
close relative of quinoa
Several other species of wheat have
also been domesticated, some very early in the history of agriculture:
- Spelt,
a close relative of common wheat
- Einkorn,
a wheat species with a single grain
- Emmer,
one of the first crops domesticated in the Fertile Crescent
- Durum,
the only tetraploid species of wheat currently cultivated, used to make semolina
- Kamut,
an ancient relative of durum with an unknown history
Farming
While each individual species has
its own peculiarities, the cultivation of all cereal crops is similar. Most are
annual plants;
consequently one planting yields one harvest. Wheat, rye, triticale, oats,
barley, and spelt are the "cool-season" cereals.[citation needed] These are hardy plants that grow well in moderate weather
and cease to grow in hot weather (approximately 30 °C but this varies by
species and variety). The "warm-season" cereals are tender and prefer
hot weather. Barley and rye are the hardiest cereals, able to overwinter in the
subarctic
and Siberia.
Many cool-season cereals are grown in the tropics. However, some are only grown
in cooler highlands, where it may be possible to grow multiple crops in a year.
For a few decades, however, there
has also been increasing interest in perennial
grain plants. This interest developed due to advantages in erosion control,
reduced need of fertiliser, and potential lowered costs to the farmer. Though
research is still in early stages, The Land Institute in Salina, Kansas has been able to create a few cultivars
that produce a fairly good crop yield.[5]
Planting
The warm-season cereals are grown in
tropical lowlands year-round and in temperate climates during the frost-free
season. Rice is commonly grown in flooded fields, though some strains are grown
on dry land. Other warm climate cereals, such as sorghum,
are adapted to arid conditions.
Cool-season cereals are well-adapted
to temperate climates. Most varieties of a particular species are either winter
or spring types. Winter varieties are sown in the autumn, germinate and
grow vegetatively, then become dormant
during winter. They resume growing in the springtime and mature in late spring
or early summer. This cultivation system makes optimal use of water and frees
the land for another crop early in the growing season.
Winter varieties do not flower until
springtime because they require vernalization:
exposure to low temperature for a genetically determined length of time. Where
winters are too warm for vernalization or exceed the hardiness of the crop
(which varies by species and variety), farmers grow spring varieties. Spring
cereals are planted in early springtime and mature later that same summer,
without vernalization. Spring cereals typically require more irrigation and
yield less than winter cereals.
Period
Once the cereal plants have grown
their seeds, they have completed their life cycle. The plants die and become brown and dry. As soon as the
parent plants and their seed kernels are reasonably dry, harvest can begin.
In developed countries, cereal crops
are universally machine-harvested, typically using a combine harvester, which cuts, threshes,
and winnows
the grain during a single pass across the field. In developing countries, a
variety of harvesting methods are in use, depending on the cost of labor, from
combines to hand tools such as the scythe or cradle.
If a crop is harvested during wet
weather, the grain may not dry adequately in the field to prevent spoilage
during its storage. In this case, the grain is sent to a dehydrating facility,
where artificial heat dries it.
In North America, farmers commonly
deliver their newly harvested grain to a grain elevator,
a large storage facility that consolidates the crops of many farmers. The
farmer may sell the grain at the time of delivery or maintain ownership of a
share of grain in the pool for later sale. Storage facilities should be
protected from small grain pests, rodents and birds.
Nutritional
facts
Some grains are deficient in the essential amino acid lysine. That is why a multitude of vegetarian cultures, in order
to get a balanced diet, combine their diet of grains with legumes.
Many legumes, on the other hand, are deficient in the essential amino acid methionine,
which grains contain. Thus a combination of legumes with grains
forms a well-balanced diet for vegetarians. Common examples of such
combinations are dal
(lentils) with rice
by South Indians
and Bengalis, dal with wheat in Pakistan
and North India, and beans with corn tortillas, tofu with rice, and peanut butter
with wheat bread (as sandwiches) in several other cultures, including
Americans.[6]
The amount of crude protein found in grain is measured as Grain Crude Protein
Concentration.[7]
The entire wiki article, with pictures
and references, can be found at: http://en.wikipedia.org/wiki/Cereal
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