highlights of the plant

8/8/2019 Highlights of the Plant

http://slidepdf.com/reader/full/highlights-of-the-plant 1/8

Highlights of the Plant

Nature of Business : Flour Production (through wheat grinding)

Plant/Factory : Fully automaticForeign Machinery Component: 40% - Czech & Spanish Origin

Special Products : Baking Flour

Other Products : Bran, White Flour & By-products

Grinding Capacity : 120 tons per day

Employees : 50

Customers : 95

Plant Location : Korangi Industrial Area Port City of Karachi Pakistan.

BACKGROUND

Flour is a finely ground powder pr epar ed f rom gr ain or other starchy plant f oods and used in

baking. Although f lour can be made f rom a wide var iety of plants, the vast major ity is made

f rom wheat. Dough made f rom wheat f lour is particularly well suited to baking br ead because it

contains a lar ge amount of gluten, a su bstance com posed of strong, elastic proteins. The gluten

f orms a networ k throughout the dough, tr apping the gases which ar e f ormed by yeast, baking

powder , or other leavening agents. This causes the dough to r ise, r esulting in light, sof t br ead.

RAW MATERIAL

Although most f lour is made f rom wheat, it can also be made f rom other starchy plant f oods.

These include barley, buck wheat, cor n, lima beans, oats, peanuts, potatoes, soy beans, r ice, and

rye. Many var ieties of wheat exist f or use in making f lour . In gener al, wheat is either har d

(containing 11-18% protein) or sof t (containing 8-11% protein). Flour intended to be used to

bake br ead is made f rom har d wheat. The high percentage of protein in har d wheat means the

dough will have mor e gluten, allowing it to r ise mor e than sof t wheat f lour . Flour intended to be

used to bake cakes and pastry is made f rom sof t wheat. All-pur pose f lour is made f rom a blend

of sof t and har d wheat. Durum wheat is a special var iety of har d wheat, which is used to make a

kind of f lour called semolina. Semolina is most of ten used to make pasta.

Flour usually contains a small amount of additives. Bleaching agents such as benzoyl peroxide

ar e added to make the f lour mor e white. Oxidizing agents (also known as im prover s) such as



potassium bromate, chlor ine dioxide, and azodicar bonamide ar e added to enhance the baking

quality of the f lour . These agents ar e added in a few parts per million. Self-r ising f lour contains

salt and a leavening agent such as calcium phosphate. It is used to make baked goods without the

need to add yeast or baking powder . Most states r equir e f lour to contain added vitamins and

miner als to r eplace those lost dur ing milling. The most im portant of these ar e iron and the B

vitamins, especially thiamin, r ibof lavin, and niacin.

GRADING THE WHEAT

y Wheat is r eceived at the f lour mill and inspected. Sam ples of wheat ar e taken f or physical and

chemical analysis. The wheat is gr aded based on sever al factor s, the most im portant of which is

the protein content. The wheat is stor ed in silos with wheat of the same gr ade until needed f or

milling. All the wheat is fir st dro pped in the ar ea shown in the pictur e f rom wher e it goes f or

production.

y

Bef or e wheat can be ground into f lour it must be f r ee of f or eign matter . This r equir es sever al differ ent

cleaning processes. At each step of pur ification the wheat is inspected and pur ified. The pur if ying

machine is called the Washing Machine. The machine pur ifies the wheat. The wheat washed today can be

used f or f urther processing af ter minimum of 12 hour s.



The machine passes the wheat over a ser ies of metal scr eens. The wheat and other small particles pass

through the scr een while lar ge o bjects such as sticks and rocks ar e r emoved.

The wheat next passes through an aspir ator . This device wor ks like a vacuum cleaner . The aspir ator sucks

u p f or eign matter which is lighter than the wheat and r emoves it. Other f or eign o bjects ar e r emoved in

var ious ways. One device, known as a disk separ ator , moves the wheat over a ser ies of disks with

indentations that collect o bjects the size of a gr ain of wheat. Smaller or lar ger o bjects pass over the disks

and ar e r emoved.

Another device, known as a spir al seed separ ator , makes use of the fact that wheat gr ains ar e oval while

most other plant seeds ar e round. The wheat moves down a r apidly spinning cylinder . The oval wheat

gr ains tend to move towar d the center of the cylinder while the round seeds tend to move to the sides of

the cylinder , wher e they ar e r emoved.

Other methods used to pur if y wheat include magnets to r emove small pieces of metal, scour er s to scr ape

off dirt and hair , and electronic color sorting machines to r emove mater ial which is not the same color as

wheat.The pur ified wheat is washed in warm water and placed in a centr if uge to be spun dry. Dur ing this

process any r emaining f or eign matter is washed away.

The moistur e content of the wheat must now be controlled to allow the outer layer of br an to be r emoved

efficiently dur ing gr inding. This process is known as conditioning or tem per ing. Sever al methods exist of

controlling the amount of water pr esent within each gr ain of wheat. Usually this involves adding, r ather

than r emoving, moistur e. Cold conditioning involves soaking the wheat in cold water f or one to thr ee

days. Warm conditioning involves soaking the wheat in water at a tem per atur e of 115°F (46°C) f or 60-90

minutes and letting it r est f or one day. Hot conditioning involves soaking the wheat in water at a

tem per atur e of 140°F (60°C) f or a short per iod of time. This method is difficult to control and is r ar ely

used. Instead of water , wheat may also be conditioned with steam at var ious tem per atur es and pr essur es

f or var ious amounts of time. If conditioning r esults in too much moistur e, or if the wheat happens to betoo moist af ter pur ification, water can be r emoved by vacuum dryer s.



GRINDING THE WHEAT

y Wheat of different grades and moistures is blended together to obtain a batch of wheat

with the characteristics necessary to make the kind of flour being manufactured. At this

point, the wheat may be processed in an Entoleter, a trade name for a device with rapidly

spinning disks which hurl the grains of wheat against small metal pins. Those grains

which crack are considered to be unsuitable for grinding and are removed.

y The wheat moves between two large metal rollers known as breaker rolls. These rollers

are of two different sizes and move at different speeds. They also contain spiral grooves

which crack open the grains of wheat and begin to separate the interior of the wheat

from the outer layer of bran. The product of the breaker rolls passes through metal sieves

to separate it into three categories. The finest material resembles a coarse flour and is

known as middlings or farina. Larger pieces of the interior are known as semolina. The

third category consists of pieces of the interior which are still attached to the bran. The

middlings move to the middlings purifier and the other materials move to another pair of

breaker rolls. About four or five pairs of breaker rolls are needed to produce the

necessary amount of middlings.

y The middlings purifier moves the middlings over a vibrating screen. Air is blown up

through the screen to remove the lighter pieces of bran which are mixed with the

middlings. The middlings pass through the screen to be more finely ground.y Middlings are ground into flour by pairs of large, smooth metal rollers. Each time the

flour is ground it passes through sieves to separate it into flours of different fineness.

These sieves are made of metal wire when the flour is coarse, but are made of nylon or

silk when the flour is fine. By sifting, separating, and regrinding the flour, several

different grades of flour are produced at the same time. These are combined as needed to

produce the desired final products.



PROCESSING THE FLOUR

y Small amounts of bleaching agents and oxidizing agents are usually added to the flour

after milling. Vitamins and minerals are added as required by law to produce enriched

flour. Leavening agents and salt are added to produce self-rising flour. The flour is

matured for one or two months.

y The last step is packing the flour into cloth bags.

highlights of the plant

Documents