Transcript CORN - amir yasin

CORN
Scientific Classification
Kingdom :
Plantae
Order :
Poales
Family :
Poacae
Genus :
Zea
Species :
Z.mays
Binomial Name :
Zea mays L.
HISTORY
Maize known in many English speaking
countries as corn.
A grass domesticated by indigenous peoples
in Meso america in prehistoric times.
Between 1250 and 1700 nearly the whole
continent had gained access to the crop.
After European contact with Americas
explorers and traders introduced it to the
Europe and other countries.
Structure and Physiology
Maize stem superficially resemble bamboo canes
and internodes can reach 20-30cm.
Has a distinct growth form the lower leaves being
like broad flags 50-100cm long and 5-10cm wide.
The stems are erect 2-3m in hieght with many nodes
casting of flag-leaves at every node.
Under these leaves and close to the stem grow the
ears.They grow about three millimeters a day.
Structure and Physiology
Stalks ears and silk
Female inflorescense
Seeds Grains or Maize Kernels
The kernel of maize has a pericarp of the fruit fused
with seed coat typical of the grases and the entire
kernel is often refered to as seed.
The grains are about the size of peas and adhere in
regular rows round a pithy substance forms the ear
An ear contains from 200-400 kernels and is from
4-10 inches in length.
VARAITIES OF CORN
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NC-205
NC-206
YHD-555
BABAR 50
HYBRID-3
C-919
P30-12
P-3060
EV-1098
EV-5098
EV-6098
Importance and Role
Maize is the third most important cereal crop
after rice and wheat.These three crops supply 57%
of mankinds calories.
Per hectare maize has the highest average production
and the rate of increase in average global yield is
twice that of rice and four times that of wheat.
Maize thus has huge potential to feed a growing
human population.
Currently it’s a staple food in sub-saharan Africa
Asia and Latin America.
Genetics
Exotic varieties of maize are collected to add
genetic diversity when selectively breeding new
domestic strains.
Maize has 10 chromosomes (n=10)
The combined length of the chromosomes is
1500 cM.
Forms of Maize
Many forms of maize are used for food sometimes classified as various subspecies related to the
amount of starch they had:
- Flour Corn
- Pop Corn
- Dent Corn
- Flint Corn
- Sweet Corn
- Waxy Corn
- Pod Corn
- Amylomaize
Chemical Composition of Maize Kernel(%)
Chemical
Component
Pericarp
Endosperm Germ
Protein
3.7
8.0
18.4
Ether Extract 1.0
0.8
33.2
Crude Fiber 86.7
2.7
8.8
Ash
0.8
0.3
10.5
Starch
7.3
87.6
8.3
Sugar
0.34
0.62
10.8
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Nutritional Value Per 100g(Seeds only)
Energy
Carbohydrates
Sugars
Dietry Fiber
Fat
Protein
Tryptophan
Threonin
Isoleucine
Leucine
Lysine
Metheonine
Cystine
360kj
19.02g
3.22g
2.7g
1.18g
3.22g
0.023g
0.129g
0.129g
0.348g
0.137g
0.067g
0.026g
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Nutritional Value per 100g (seed only)
Phenylalanine
Tyrocine
Valine
Arginine
Histedine
Alanine
Aspartic Acid
Glutamic Acid
Glycine
Proline
Serine
Water
0.150g
0.123g
0.185g
0.131g
0.089g
0.295g
0.244g
0.636g
0.127g
0.292g
0.153g
75.96g
Types of Maize for different products
• There are number of types of maize
• Dent maize (The common feed & Starch crop)
• The high sugar mutant sweet corn(flint
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maize)Common in asia.
Pop corn with an hard endosperm that pops when
heated.
Floury maize (used for soups etc.)
Waxy maize and high lysine maize(Valuable source
of the essential amino acids lysine)
Maize Silage is an important feed source for cattle.
Plants are chopped, fermented and fed as a high
energy,low protein complement to high protein
pasture.
Maize Products
• About 7-15% of the grain goes to industry:
corn oil,corn starch (includes syrups,
sweeteners, high fructosecorn syrup,
thickeners, hardeners for paper, glue,
cornsugars). It is increasingly fermented to
produce ethanol,especially in the US.
• Maize stover (the bit left after grain harvest)
is best in corporated back into the soil, but is
often used as forage or fuel in the 3rd World,
and may also be fermented to give ethanol.
MAIZE PRODUCTS
• Beer
Beer manufacturing is a process of treating
malt to convert and extract the barley starch to
fermentable sugars using the amyloytic enzymes
present in malt followed by yeast fermentation.
However, demand for lighter, less filling beer, especially
in the U.S., has permitted use of more refined
carbohydrate sources of two types:a) dry adjuncts,
primarily dry milled corn grits, broken rice, refined corn
starch, and more recently, dextrose.b) liquid adjuncts,
namely corn syrups
• Cake Mixes
Cake mixes use a pregelatinized corn starch
that will form a paste in cold or warm water. In baked
goods that use yeast for rising, dextrose is used as a
yeast nutrient.
• Candies
Corn syrup is used in hard candies to
provide a body giving them chewiness and a desirable
mouthfeel without excessive sweetness. Candies that
are coated use a pyrodextrin corn starch for the
coating.
• Carbonated Beverages
CokeHigh fructose corn syrup (HFCS)
blended with sucrose in a 50/50 blend is sweeter than
the same concentration of sucrose. The use of HFCS in
carbonated beverages is common throughout Canada
and the U.S.
• CookiesCorn
in cookies.
starch, corn flour or dextrose may be found
• Corn Flakes
The flaking grits are cooked to a rubbery
consistency with syrup, malt, salt and flavouring added.
After tempering, the cooked grits are flattened between
large steel rolls, followed by toasting in travelling ovens
to a golden brown colour.
• Corn Starch
Corn starch is derived from the wet milling
process and is an important manufactured product.
Some uses depend on the properties in the dry state,
but most applications relate to its properties as a
cooked, hydrated paste.
• Corn Meal
Corn meal is a popular dry corn product because
of its long shelf life. It is used to produce an assortment
of chemically leavened bread and fried products like
corn bread and muffins.
• Cosmetics
Corncobs, when finely ground, are relatively
dust free and very absorbent. This absorbency makes
corncobs useful carriers for pesticides, fertilizers,
vitamins, hand soaps, cosmetics and animal litters.
• Granola Dips/Granola Bars
Some types of Granola Dips use dextrose as a
sweetener.
• Gypsum Wallboard
Starch-containing corn flour is gelatinized during
the manufacturing process; It functions by controlling
the rate of water loss during drying of the board.
Soluble carbohydrates migrate to the surface and
control the rate of crystallization of the gypsum,
providing a strong bond between the gypsum and the
liner.
• Instant Coffee & Tea
Maltodextrins are derived from the wet milling
process. They are a dextrose equivalent product of
complete solubility but little or no sweetness.
Maltodextrins are sprayed on instant tea and coffee to
keep the granules free flowing. This solution is also
used in instant soup mixes or other packages where the
contents must be be kept free flowing.
• Mars Bar & Twix Bar
Many candy bars contain corn syrup.
• Paint and Varnish
Tetrahydrofurfuryl alcohol is a resin developed
from processing corncobs. These resins are useful in the
paint and varnish industry as solvents for dyes, resins,
and lacquers.
• Pharmaceuticals
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Aspirin - an oxidized starch paste, which dries to a
clear, adherent, continuous film, is spread in a thin layer
over the aspirin.
2. Intravenous - some IVs consist of dextrose and
water solutions.
3. Antibiotics - preferred carbohydrate sources are corn
syrup, dextrose, corn starch, lactose and sucrose.
Cornsteep liquor was early found to provide a ready
source of soluble nitrogenous nutrients plus unknown
growth factors that stimulate antibiotic production.Over
85 different types of antibiotics are produced using
corn.
• Yogurt
Some of the different brands of yogurt use corn
syrup as a sweetener.
• Paper Products
Paper products use raw starch in the manufacturing
process. The properties of high paste viscosity and
strong gels are useful in specially coated papers.
Pyrodextrins are also used for paper manufacturing for
the adhesive property on remoistenable gums for
postage stamps and packaging tape.
• Snack Foods - Corn Chips &
Doritos
These snack foods are generally made from whole
corn (cornmeal). The high starch content of cornmeal
and flour is important in giving a high puff in
preparation of extruded (pressed) snack products in
which a delicate corn flavour is desired.
• Spark Plugs
Starch is used in the production of the porcelain
part of spark plugs.
• Tire, Rubber
In the production of tires, corn starch is sprinkled
on the molds before pouring the rubber, to prevent the
rubber from sticking to the molds.
• Toothpaste
Sorbitol, which is produced from the corn sugar
dextrose, is used in toothpaste as a low-calorie, watersoluble, bulking agent.
• Whiskey
The major carbohydrate in the production of whiskey
is corn.A typical Canadian whiskey is made from a
mixture of about 90% corn, 5% rye, and 5% barley
malt.