Prepared by
Id no 1227/05
HARAMAYA UNIVERSITY
INSTITUTE OF TECHNOLOGY
DEPARTMENT OF FOOD TECHNOLOGY AND PROCESS
ENGINEERING
HOSTED BY AFRICA PRIVATE LIMITED COMPANY
INTERNSHIP DURATION – FROM DECEMBER 2016 TO FEBRUARY 2017
Submission date- march-15-2017
HARAMAYA UNIVERSITY
INTERNSHIP REPORT
Declaration
This report paper is a short description of my four-month internship practice at one of the finest
food complexes on my home town ADAMA which goes by the name of AFRICA PLC. This report includes
process steps of production involved in each and every part of the hosting company. I have experienced
through different part of the production area step by step to help me understand the flow of each production
and inspection methods as instructed by Mr. DEMELASH the head of pasta production unit and a mentor
of mine and 3 fellow students from JIMMA UNIVERSITY. I believe this document briefly explains what
I have learned in my time at AFRICA PLC.
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Acknowledgement
For starters, the help that I’ve been offered since day one from every one that had to do with anything I
intended to involve in was extra ordinary. I would like to thank the personnel that made it easy for me. They
all were very open to supply any resources I needed. Everybody was keen to let me know everything they
know. I deeply appreciate the help I’ve been offered from them.
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Table of contents
DECLARATION................................................................................................................................................................. I
ACKNOWLEDGEMENT ...................................................................................................................................................... II
EXECUTIVE SUMMERY..................................................................................................................................................... VI
INTRODUCTION ............................................................................................................................................................... I
Background and profile of the company ................................................................................................................ i
Objective of the company ...................................................................................................................................... i
Mission .................................................................................................................................................................. ii
Vision..................................................................................................................................................................... ii
Goals ..................................................................................................................................................................... ii
Location................................................................................................................................................................. ii
Food safety policy of the company ....................................................................................................................... ii
Main products of the company ............................................................................................................................ iii
Pasta.................................................................................................................................................................................. iii
Macaroni ........................................................................................................................................................................... iii
Wheat flour ....................................................................................................................................................................... iii
Main customers and end users ............................................................................................................................ iii
STATEMENT OF PROBLEM................................................................................................................................................ IV
CHAPTER 1 ............................................................................................................................................................. 1
1.
WHEAT MILLING PLANT...........................................................................................................................................1
1.1 Introduction.....................................................................................................................................................1
1.2 Pre-cleaning ....................................................................................................................................................1
1.3 Cleaning ..........................................................................................................................................................2
Selector .............................................................................................................................................................................. 2
Dry stoner ........................................................................................................................................................................... 2
Radial separator ................................................................................................................................................................. 3
Radial scourer ................................................................................................................................................................ 3
Double trieur ...................................................................................................................................................................... 3
1.4 Wheat conditioning.........................................................................................................................................5
1.5 Milling .............................................................................................................................................................7
Roller mill ........................................................................................................................................................................... 8
Sifter (plan sifter) ............................................................................................................................................................. 10
Purifier .............................................................................................................................................................................. 11
Bran finisher ..................................................................................................................................................................... 12
1.6 Packaging and storing...................................................................................................................................12
CHAPTER 2 ........................................................................................................................................................... 13
2.
PASTA PRODUCTION PLANT....................................................................................................................................13
2.1 introduction...................................................................................................................................................13
2.2 Long cut pasta ...............................................................................................................................................13
2.2.1 Pasta Ingredients ..................................................................................................................................................... 13
2.2.2 Process description ................................................................................................................................................. 13
Dosing unit .................................................................................................................................................................. 14
Pre-mixer ..................................................................................................................................................................... 15
Mixing through tank .................................................................................................................................................... 15
Extrusion group ........................................................................................................................................................... 16
Head block group ........................................................................................................................................................ 16
Head ventilation .......................................................................................................................................................... 17
The Spreader – ............................................................................................................................................................ 17
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Lower cutter group ...................................................................................................................................................... 17
Scrap recovery group................................................................................................................................................... 18
Drying and cooling units .............................................................................................................................................. 18
Pre drier ....................................................................................................................................................................... 19
1st degree drying .......................................................................................................................................................... 19
2nd degree drying ......................................................................................................................................................... 19
Cooling unit ................................................................................................................................................................. 19
Packaging ..................................................................................................................................................................... 19
2.3 Short cut pasta (macaroni) processing .........................................................................................................21
2.3.1 Introduction............................................................................................................................................................. 21
2.3.2 Ingredients .............................................................................................................................................................. 21
2.3.3 Process description ................................................................................................................................................. 21
Flour dosing unit .......................................................................................................................................................... 21
Water dosing unit ........................................................................................................................................................ 21
Pre-mixer ..................................................................................................................................................................... 21
Mixing through tank .................................................................................................................................................... 21
Extrusion group ........................................................................................................................................................... 21
Pre drying .................................................................................................................................................................... 22
Drier............................................................................................................................................................................. 22
Cooler- ......................................................................................................................................................................... 22
Packaging ..................................................................................................................................................................... 23
CHAPTER 3 ........................................................................................................................................................... 24
3.
QUALITY CONTROL AND BASIC WATER AND AIR SUPPLY UNITS .......................................................................................24
3.1.
Quality control analysis..........................................................................................................................24
3.1.1. Quality analysis of raw wheat ............................................................................................................................ 24
Moisture content determination................................................................................................................................. 24
Hectoliter weight ......................................................................................................................................................... 25
Impurity ....................................................................................................................................................................... 25
Protein (gluten) content .............................................................................................................................................. 25
3.1.2. Production line and final product quality analysis in pasta &macaroni line ........................................................... 26
3.2. Water and air supply room .......................................................................................................................... 26
Boiler ........................................................................................................................................................................... 26
Chiller - ........................................................................................................................................................................ 27
Air compressor ............................................................................................................................................................ 27
Water treatment ......................................................................................................................................................... 28
CHAPTER 4 ........................................................................................................................................................... 29
4.
OVER ALL BENEFITS ..............................................................................................................................................29
4.1. Improving Practical skill ...............................................................................................................................29
4.2. Update theoretical knowledge .....................................................................................................................29
4.3. Improving interpersonal communication skills ............................................................................................29
4.4. Work ethics ..................................................................................................................................................29
4.5. Entrepreneurship..........................................................................................................................................29
Self-motivation- ................................................................................................................................................................ 29
Self confidence ................................................................................................................................................................. 29
CHAPTER 5 ........................................................................................................................................................... 30
5.
CONCLUSION AND RECOMMENDATION ....................................................................................................................30
5.1. conclusion ....................................................................................................................................................30
5.2. Recommendation .........................................................................................................................................31
REFERENCE .................................................................................................................................................................32
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APPENDIX ...................................................................................................................................................................33
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Executive summery
The aim of this report is to explain what I did and learned during my internship period in Africa plc. The
main purpose of internship is to develop skills in the application of theory to practical work situations, to
provide students the opportunity to test their interest in a particular career before permanent commitments
are made and to motivate students to continue their education. I have discussed about every major aspects
of wheat flour production, pasta and macaroni production processes and quality control laboratories, which
I observed and perceived during my internship program.
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Introduction
Africa plc. is a food manufacturing company. They produce flour, pasta and macaroni. They have
two different types of machinery for each product. Which is very important for me to understand
the developments of the machinery according to different angles such as, increase in efficiency
and capacity, design integrity with safety, decrease in production time and waste. To top it all off,
it helped to be able to get a better understanding of different types of working principles in one
place which is very important for me as an engineering student
I was involved in practices of raw material analysis and quality determination of different stages
of production in the laboratory, then I moved to the flour house and learned the working principles
of different machineries used in the milling process and before that raw material (wheat)
purification and conditioning processes. After that, I moved to the pasta and macaroni production
unit. In this section, I have understood and practiced the production of pasta from the beginning to
the end product.
Background and profile of the company
Africa plc is profit based company established in November 1999 for the purpose of engaging
mainly in the business of food processing, with the initial capital investments of 5,000,000 ETB.
The company is owned by private share holder and over seen by the general manager Mr. Hussen
Mohammed Noor. The total area of the company is 10,000 Sq. m. It is an ISO 22000:2005 certified
company.
ISO 22000:2005 is the food safety management system with the objective of the goal to provide
as a good production of Food Company. And also HACCP is an overall process control system
and it takes a variety of different kinds of knowledge and experience to develop a good system.
Hence the ISO 22000:2005 implementation which is also responsible for HACCP implementation
as part of the ISO 22000:2005 implementation is represented by most of the main function of the
company, for instance, technical, production, quality control department /teams/ and other relevant
units /department/.
Africa plc is equipped with Modern Milling Pasta and Macaroni manufacturing technology. The
average design annual production capacity for Wheat flour 1200 Qtl/ hr. Pasta 2500 kg /hr.,
Macaroni 2400 kg/ hr. and Bran / for animal feed/ 324kg/ hr. . Currently Africa plc produced
about 5 different shapes of Pasta and Macaroni. The company’s pasta and macaroni products are
namely Buona, Roma and Rosa. Wheat flour is another product of the company. The company
have two milling houses, two pasta and two macaroni machineries. Although during my time the
oldest machineries of both pasta and macaroni were on maintenance. I had a chance to see the old
pasta machine working though. But the old macaroni was out for my entire experience in there.
Objective of the company
Objectives are the end results of planed activity they state what is to be accomplished, when to be
accomplished, where to be accomplished etc.
•
To create better product at lower cost for maximization profit.
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•
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Acquiring quality raw material and producing quality product that will meet the demand.
Creating job opportunity for the nation as well as for relatives.
Mission
The mission of Africa plc is
•
•
•
To provide modern food complex to the customers starting from Oromia region at Adama
and cover all the region of the country.
To participate on the economic growth of the country.
To produce and provide safe Pasta, macaroni and wheat flour products
Vision
It refers to the future ambition of the organization there is the intentions which express what
organization need to be come in the future
•
•
To become a leader company by supplying a quality product.
To ensure sustainable profitability.
Goals
Africa plc have the following goals: •
•
•
•
Good working relationship between management and employee
Contribution of every member for their goal such that producing quality of wheat
flour, macaroni and pasta.
Respect for the rule of law of food manufacturing and good manufacturing practice.
Respecting itself and respecting others.
Location
Africa plc. Is located in Adama, Ethiopia, Kebele 13
* Tele No: 251-022-111-42-31 or 022-111-47-07
* Fax No: 022-111-54-63* P.O.Box : 929
* E-Mail Address: - africaff@ethionet.et
Food safety policy of the company
Africa plc. is strongly committed to produce and provide safe Pasta, macaroni and wheat flour
products that fulfill applicable international, national and mutually agreed food safety and
quality standards, regulatory and statutory requirements to the highest satisfaction of its
customers. The key measure of its success is exceeding the need expectation of the customers
with strong commitment and participation of the management in addition to that employees at
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all levels, the company implement, maintain and continually improve the food safety
management system; train and aware every employee; ensure allocation and effective
utilization of resource ; establish effective communication arrangement; prepare and respond
to emergency situation or accidents; and ensure the continuing suitability, adequacy and
effectiveness of the system.
The policy is communicated, understood, implemented, reviewed, updated and maintained at
all levels of the organization.
Main products of the company
Africa plc mainly produces the following products
Pasta
In this pasta production currently the company produces three pasta products; these are
Buona, Roma, and Rosa. The only difference is the name of the pasta.
Nutritional value: - carbohydrate 76.25gram, energy 355 kcal, protein (nx
6.25) 12.14 gram, fat-lipid 1.47gram.
packed by polyethylene film 500gram and 1kg by paper packed for
commercial product
Shelf life: - 1year, if they are stored in cool and dry storage condition.
Macaroni
In this macaroni production currently the company produces three shapes of macaroni
products; these are Spiral, Big elbow, and Small elbow.
Nutritional value: - the same as pasta product.
Packed by polyethylene film 500gram, and 25kg by cellophane bag for commercial
product.
Shelf life; best before date is 1 year.
Wheat flour
Packed by cellophane bag 25kg for commercial product and bran or animal feed is miner
product of the company
Main customers and end users
The consumers of the pasta, macaroni and wheat flour products is for children, all public
and kinds of vulnerable groups, disaster stricken persons including refugees and displaced persons.
And also the companies have different clients or customers such as governmental and
nongovernmental organizations.
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Statement of problem
Even though the information I gained from every working personnel in production area was great,
it wasn’t good enough to support my theoretical knowledge in most part of my experience. The
information was based on practical reputation and most of them have wrong scientific explanation
on how the process was going.
To deal with the challenge, I had to get the proper written document on every machinery installed
and luckily I have found it and the supervisor and his stuff made sure I could access it at any time
I wanted.
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Chapter 1
1. Wheat milling plant
1.1 Introduction
Africa plc has 2 huge milling plants. In the first milling plant, the wheat storage and reception
room is side to side with the flour house. So first treatment and purification of wheat starts in it.
Before the raw material get purchased, quality analysis and grading is applied by the laboratory
taking random samples from the vehicle outside the property of the company applying different
sensory evaluation. After the purchase, based on the quality of the raw material, storage will be
arranged. Then when the demanded type of flour quality is instructed the wheat for example, pasta
grade (which is hard wheat), will be introduced to the first storage tank (silo) to start the milling
process beginning with preclearing. Before the grain can start the milling process, it has to be
thoroughly cleansed and conditioned.
1.2 Pre-cleaning
Then from the tank, the bucket elevator transfers the wheat to the machine called selector. this
machine has magnetic separator at the top feed receptor to collect any ferrous materials from the
wheat. Different sized sieves, larger sieves to separate impurities which are above the size of wheat
and smaller sieves to separate those which are small in size from the wheat. The machine uses
vibration to support this and the aspiration system is installed to get rid of dust out of the feed. The
aspirator is connected to dust cyclone.
Fig. dust cyclone
Dust saturated air enters to the dust cyclone from upside to the internal side tangential (angular)
and enters to body vertical. Dusty air which enters to the body generates compulsory vortex. The
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dust specks which enters to this compulsory vortex are thrown to the wall by centrifugal force.
Friction force on the wall pushes dust speak down and sends to the outlet. The air which exits from
free vortex and which abandons the dust, exists from pipe of upside of cyclone and to the
atmosphere. Then the dust is collected with bags.
1.3 Cleaning
After the pre cleaning process, the wheat transferred in 2 ways in Africa plc. according to demand.
The first way uses conveyor and a bucket elevator to transport the wheat in to the second storage
tank. The second way uses blower to transport the wheat to the second milling plant storage tank.
The second milling plant doesn’t have its own pre cleaning section so it receives pre cleaned wheat
from the storage room.
Fig. blower
From the second silo, the wheat is introduced to a chain of cleaning parameters. The bottom of the
silo is equipped with metered feeding equipment called blending machine to determine and
control the flow of the wheat for proper practice of cleaning avoiding overflow and for use of full
potential in order to use energy efficiently. There is a screw conveyor at the bottom of the silo
feeder. Then the bucket elevator receives the wheat and transport it to the top floor of the cleaning
plant.
The cleansing process involves passing the grain through several machines that will remove any
contamination in the batch of grain. These machines include a selector, dry stoner, radial separator,
double trieur, and magnet which is installed in most of the machines feeding section.
Selector
At the top, the machine called selector receives the wheat in 2 inlet tubes and 2 magnetic
separators. The rest of the machine uses pretty similar to the previous one which is used in pre
cleaning unit just smaller in size.
Dry stoner
The treated wheat that comes out of the selector goes straight to the machine called dry stoner.
This machine treats the wheat based on density difference. it separates denser material basically
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stone which are similar in size with the wheat by the help of vibration and its elevated structure. It
is connected to an aspiration system to collect dust and light materials. All the leftovers from the
treatment line will go to their individual collecting bags.
Fig. dry stoner
Radial separator which is located at the top of the plant layout, receives previously treated wheat
from the dry stoner by the use of a bucket elevator. It is a combination of two machines working
together. Radial scourer (right side of fig) and radial tarar (left side of the fig.).
Fig. radial separator
Radial scourer separates the dust, wheat shell and wheat whiskers by using impact action against
the wall and conveyed to the outlet. Radial tarar is connected to radial scourer separates low
density materials by using aspiration system.
Double trieur - is a round horizontal cylinder which is used to separate smaller impurities from
the wheat. The inside of the cylinder has pockets smaller in size from wheat grain and rotates.
There is a ‘V’ shaped basin in the middle to collect the smaller impurities and conveys it to the
outlet. Then the treated grains pass to the second cylinder and have the same process again.
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Fig. double trieur
After treatment by double trieur, the wheat grains transported straight to the conditioning machine
called dampener by the means of bucket elevator. After passing through this chain of process you
can rest assured that the grain is clear of any other substances. The conditioning procedure mixes
water with the grain to get the right moisture level. This will make the grain easier to mill.
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1.4 Wheat conditioning
Now the wheat is ready to be conditioned for milling. This is called tempering. Water is added in
precise amounts to toughen the bran and mellow the inner endosperm.
Why is it necessary to add water?
Mellowing the inner endosperm
•
•
•
Flour extraction can be increased
Power consumption/ noise level of roller mills reduced
Flour ash content reduced
Toughening of the bran
•
•
•
Bran tends to break less and remain in larger pieces
Large bran flakes can be effectively cleaned
Less bran specs (smaller pieces) in the flour
Adjustments of the flour mixture
•
•
•
Constant moisture level = constant milling conditions
Constant moisture level = constant flour quality for further productions
Profitability of the company
Factors influencing tempering time
Wheat hardness
⇒ The harder the wheat the longer the tempering time
Protein content
⇒ The higher the protein content the longer the tempering time
The wheat and the ambient temperature
⇒ The lower the wheat temperature and the ambient temperature the longer the tempering
time
Moisture content
⇒ The lower Initial moisture content the longer the tempering time
⇒ The higher the target moisture the longer the tempering time
Table 1. Tempering time and moisture content applied in Africa plc
Wheat type
hard
Semi hard
Tempering time
24-48 hrs.
18-24 hrs.
5
Moisture added
16.0-17.5 %
15.5-16%
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Semi soft
Soft wheat
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12-18 hrs.
6-12 hrs.
6h
12h
15.0-15.5%
14.5-15.0%
18h
3h
6h
Soft wheat water penetration
12h
18h
hard wheat water penetration
The calculations formula of dampening water flow rate;
1st conditioning:
.
.
100
.
100
.
2nd conditioning:
.
. 2
100
. 2
100
. 2
Final m.c = is the targeted moisture content to be achieved in the conditioning process
High speed dampening machine is used for conditioning process in Africa Plc.
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Fig. dampening machine
Why high speed dampening?
Water has a rather strong surface tension which prevents an even water distribution on the grain
under regular conditions. With high speed dampening and its high centrifugal forces, the surface
tension can be overcome and a thin and uniform water layer can be created on the kernel surface.
1.5 Milling
The wheat kernels are now in far better condition than when they arrived at the mill and are ready
to be milled into flour. Milling is the process used to grind wheat in to flour. Essentially this is the separation
of the bran and germ from the endosperm and the reduction of the endosperm to a uniform particle
size(flour). This is done by the sequence of breaking, grinding and separating operations.
After conditioning, the wheat undergoes one more treatment by radial separator attached to a
magnetic separator to make sure the feed is as clean as possible to avoid damage to the mill and to get fresh
product. After the treatment the wheat stays in a temporary tanker which is installed with sensors ready to
be introduced to the mill to facilitate appropriate rate of flow.
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Fig. temporary tank
Roller mill
From the temporary tank, the wheat introduced to the first milling machine by the means of an inlet tube.
The grain starts off by going through a pair of rollers turning in opposite directions. There are several
different types of rolling systems used to obtain the different desired results. The corrugated first break rolls
begin the separation of bran, endosperm and germ. These rollers will cause the inner endosperm to be
released.
1
2
3
4
5
Fig. roller mill
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Feed to the machine falls in to the feed tube (1) and is spread behind the upper inspection door (2), having
been sensed by the capacitance device bank of sensors. This causes the unseen feed rolls to increase or
decrease in speed when feeding the main rolls whose speed is constant. Discharge of ground stock is to the
hopper behind the lower inspection door (3) and up the pneumatic suction lift to sifters. The operator can
control & program the machine from the control pads (4). The operator can adjust & program the roller gap
at (5).
From the rolls, the grist (ground wheat) is sent way upstairs to drop through sifters. The grist is moved via
pneumatic system that mix air with the particles so they flow, almost like water, through tubes. This is a
great advance in health and safety from earlier methods of moving the grist with buckets. The pneumatic
system is connected to air jet filter to collect fine flour carried out by the air.
Fig. airlock, cyclone
fig. pneumatic fan
Fig. pneumatic system
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Each outlet from the millers down stairs has its own tube connected to its own cyclone to prevent mixing.
The pneumatic fan sucks the air ground wheat mix and carry it through the tube to the cyclone. then in the
cyclone, pressure decreases due to larger surface area at the top of the cyclone causing the denser materials
(ground wheat) to fall down. The airlock at the bottom of the cyclone prevent the air movement to facilitate
the separation process.
The pneumatic fan takes the air available in the sucking part in from the inlet part and conveys it to the
filter machine through the air outlet part which is on the side by the turning of palette sucking turbine. The
electronic air jet filter is used. In cyclones, the flour is separated from the air but some flour still remains in
the air during suction. Flour in the air sticks on the silky bags and then spread by pressured air and collected
though airlocks and by bags.
Sifter (plan sifter)
The Broken particles of wheat are introduced to huge, rotating, box-like sifter where they are shaken
through a series of screens to separate the larger from the smaller particles. Various types of the frames
allow separation in seven canals. Inside the sifter, there may be as many as 27 frames in each cabin.
Larger particles are shaken off from the top, leaving the finer flour to sift to the bottom. After being sieved,
the product is sent to the exit pipe on the lower plate. At the same time, there are watch pipes in order to
control and observe the product. The scalped particles are sent to other roll passages and particles of
endosperm are graded by size and carried to separate purifiers. The particles that pass through the finest
sieve are considered flour. The particles that do not fall through this sieve continue to go through rollers
until it is broken down into flour.
Fig. plan sifter
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Purifier
In a purifier, a controlled flow of air lifts off bran particles while at the same time a bolting cloth separates
and grades coarser fractions by size and quality. Five additional break rolls, each with successively finner
corrugations and each followed by the sifters, are used to rework the coarse stocks from the sifters and
reduce the wheat particles to granular middling that are as free from bran.
Fig. purifier
Figure number
1
2
3
4
5
6
7
Description
Channel valve
Turbulence chamber
Air valve adjustment
Sieves
Product orientation
Fine product collecting
Feeding group
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A
B
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Product inlet
Product outlet
Aspiration connection
Table. Purifier description
The reduction rolls reduce the purified, granular middling, or farina, to flour. The process is repeated over
and over again, sifters to purifiers to reducing rolls, until the maximum amount of flour is separated,
consisting of close to 75 percent of the wheat. The remaining percentage of the wheat kernel or berry is
classified as mill feed-shorts or bran.
Bran finisher
When the flour reach at this age of the process, it is about to be the last of the bran and the flour together.
While the product is flowing in to the rotating rotor, it is winnowed to the beating walls and plansifter. The
flour pieces at the increasing proportion are separated from bran. After the separation operation is finished,
bran and flour is taken out in different ways.
Fig. bran finisher
1.6 Packaging and storing
The flour extracted out of this machine will be directed to the flour line and been collected or transferred to
the flour tanks or silos. And the bran is directed to the bran collecting line.
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Chapter 2
2. Pasta production plant
2.1 introduction
A quality pasta product begins with high quality raw material. Durum wheat is ideally suited for pasta
because of its unique color, flavor and cooking qualities. Durum wheat semolina and water are mixed,
extruded and dried, to produce pasta, which contributes to a large portion of carbohydrates in the diet and
protein, yet low in fat. Pastas are also a moderate source of vitamins, such as the B vitamins and folic acid.
Because of this nutritional profile, pasta can be included as part of a healthy diet, especially in diabetics
due low glycemic index.
The processes of mixing, extrusion, drying, and packaging are all important steps in the development of a
shelf-stable, high quality product. The objective of the process is to produce a quality product by using
equipment and technique to ensure homogeneous mixing and uniformed drying. This protects the pasta’s
gluten network to ensure cooking quality and helps produce a uniformed strong product. The quality of the
end product will reflect the process by storing well, rehydrating uniformly, maintaining its shape and
producing a tasty cooked product that is desirable to the consumer.
Pastas are broadly categorized as short or long pasta and have variation in how they are pre-dried and dried.
Short pasta requires a shaking pre-dryer and less time in the drying step because of the lower surface area.
Long pasta is pre-dried by a blast of air, and due to the larger surface area, it needs longer time and multiple
steps during the drying stage. The three steps of drying are pre-drying, drying, and cooling.
There are two types of pasta based on length and other quality characteristics, short cut pasta and long cut
pasta.
2.2 Long cut pasta
The highest quality durum semolina is needed for long pasta products. It must be free from specks and
exhibit a bright yellow color. Long products, such as spaghetti, are consumed in markets worldwide.
2.2.1 Pasta Ingredients
Pasta is a mixture of semolina, made from grinding the endosperm of high-quality, hard durum wheat,
water, and salt. Durum wheat helps pasta retain its structure and shape when cooked. water and semolina
are typically combined in a ratio of 25-30 kg of water for every 100kg of dry semolina. Stiff dough is
produced after the mixture.
2.2.2 Process description
There are three processes involved in combining the ingredients of pasta: mixing, kneading, and extruding.
The flow of the inputs into the mixer is regulated by a volumetric doser because this device has precise and
constant outputs.
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A~ FLOUR FEEDING CYCLONE
B~ FLOUR DOSER
C~ WATER DOSER SYSTEM
D~ PREMIXER
E~ MIXING THROUGH TANK
F~VACUUM PLANT
G~ EXTRUSION GROUP
H~ HEAD GROUP
M, N~ SCRAPS RECOVERY GROUP
O~ DIE LIFTING HOIST
Fig. long cut pasta manufacturing unit
Dosing unit
The wheat, which is stored in tankers or silos in the milling room will be transported to the dosing unit that
is located in the pasta processing plant through a pneumatic system, then the wheat will be introduced to
the pre-mixer through a flour dosing unit which is equipped with a cyclone with an over flow and under
flow detecting sensors. These sensors will trigger the alarm if any over or under flow occurred during
processing. The cyclone is installed with an air lock to prevent air passing down to the pre-mixer through
a screw conveying feeder. The flour feeding is controlled by the speed of the conveyer which introduces
the flour into the pre mixer.
The water dosing unit is responsible for maintaining the correct proportion of water getting into the premixer. It is equipped with a cylinder and dosing plenum chamber and connected to dosing pump to pump
up water. The temperature and pressure gauges and flow meter will make sure the water has the desired
characteristic to enter for mixing. The water will be sent to the dosing unit from the boiler room at 40-50
degree Celsius.
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Pre-mixer
Semolina flour and water are combined in a pre-mixer until the dough is adequately hydrated and forms a
homogenous mixture. It generally helps to facilitate the kneading process by blending water with flour
evenly.
The pre mixer consists of;
•
•
A flour screw conveyor, to assure a constant flow to the mixer,
A mixer with paddle shaft and water injectors for a quick and regular flour imbibition from very
beginning of the operating cycle.
The entire group is stainless steal made, vacuum seal execution.
Mixing through tank
The mixture is then passed into the mixer in the next step. Initially, the mixer removes air bubbles from the
dough. The pasta presses are equipped with a vacuum chamber to remove air bubbles from the pasta before
extruding. If the air is not removed prior to extruding, small bubbles will form in the pasta which diminish
the mechanical strength and give the finished product a white, chalky appearance.
Fig. mixer
The dough is mixed in a twin shaft mixing chamber for 16-18 minutes. Each of the shafts will turn in
opposite directions, a non-centric movement, to ensure that the dough does not clump into a ball. Additional
water mixture device is placed near the mixing tank
The mixer is equipped with dough level regulation system. The system is set with two safety threshold: the
first one gives an alarm for high dough level, also decreasing the flour rotation speed and the water capacity;
the second one gives an alarm for very high dough level, the system automatically stops the dosers and
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warns the operator, who will take out manually part of the dough and fix the problem (die filter dirty, too
soft mixture, etc.); then the operator must start the machine again.
Extrusion group
The pasta is kneaded and shaped in a machine called an extruder. There are several zones in the extruder
which are involved in conveying, compacting, kneading, relaxing, and extruding the dough. Upon entering
the extruder, the hydrated semolina mixture contacts the extrusion screw first. The compression group with
vacuum seal is orthogonal to the mixing through tank and includes carbon steel cylinder including external
stainless steel jacket for the heating/cooling water circulation. The screw is exposed so that the semolina
mixture can be dropped directly from the mixer onto the screw as it turns.
The hydrated semolina is conveyed from the screw into the extrusion barrel to be compacted. Pressure
increases from approximately 0 to 2 MPa to help transform the hydrated granular semolina into a compacted
dough. During compaction, temperature also increases due to friction between the dough, screw, and walls
of the barrel. The friction is necessary to compress the dough and move it down the channel. The excess
heat is removed by a warm water jacket that engulfs the extrusion barrel, which keeps the temperature of
the dough and barrel at approximately 45°C. The ideal temperature for pasta extrusion is between 45°C and
50°C, as anything above 50°C will denature the proteins and impede in gluten matrix formation. As a result,
a soft sticky product is produced. Using a cold water jacket, as opposed to a warm one, will cool the dough
and barrel too quickly and result in undesirable dough viscosity.
The extrusion auger not only forces the dough through the die, but it also kneads the dough into a
homogeneous mass, controls the rate of production, and influences the overall quality of the finished
product. After the dough has been compacted it continues to move along the extrusion screw, where it
kneads by flowing forward and getting pushed back by pressure forces. The gluten molecules in the dough
are stretched and aligned with the directional movement of the screw. However, the flow rate of the dough
is not uniform as it moves down the extrusion screw, and consequently, causes irregular dough
development. To increase homogeneity of the dough, a kneading plate is attached to the end of the screw.
Afterwards, the dough enters the extension tube, which is used only when extruding long pasta, such as
spaghetti. The dough is allowed a brief rest before entering the die in the extension tube. By the time the
dough has reached the end of the extension tube, it is considered fully developed.
Head block group- is a head of the extrusion group consisting of head cylinder, pre-die, filter, die, head
ventilation. Pre-die is at the beginning of the shaping process by giving a cylindrical shape to the dough.
The dough then passes through a filter which has very fine sieves to block solid and oversized particles.
The die is used to shape the pasta. The shaping part of the die is coated with plastic to avoid reaction due
to high pressure. The head group has oleo dynamic cylinder which uses a one-way push and pull action for
die changing purposes.
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Fig. head block group
Head ventilation- it is consists of a hot water circulation to heat up the steel plates literally called finned
battery and the air ventilator conveys the air through a pipe to heat up the pasta coming out of the die to
prevent it from sticking.
The Spreader – Once the dough is molded and got the required shape by the rectangular die, it will be
laid on synchronized sticks by special unit called spreader. The long spaghetti stands are deposited onto a
spreader, which spreads the strands on sticks and cuts them into a uniform length as the product comes out
of the die. There are some scraps that results from the uneven flow from out of the die. The scrap is simply
collected and brought back into the mixer through the scrap return system. The pastas attached to the sticks
are transferred to the dryer.
Fig. spreader stick
Lower cutter group
After the pasta is loaded on the stick, it has no uniform length at the tip bottom. The lower cutter group
make sure the pasta has uniform length to make it available for drying and facilitate evenly drying. It is
equipped with two sharp blades moving horizontally in opposite direction. The blades have fixed position
which give every pasta curtain same length and appearance
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Fig. cutter blade
Scrap recovery group
The lower cutter blades cut off the pasta and left it in the belt bellow. The belt collects and throw it on the
pneumatic scrap recovery device. The device push the scrap up to the mixer to get it remixed.
Stick return group- is responsible for returning the unloaded stick back to position. It operates under the
processing line.
Drying and cooling units
Drying is the most difficult and critical step to control in the pasta production process. The
objective of drying is to lower the moisture content of the pasta from approximately 31 percent to 12
to 13 percent so that the finished product will be hard, retain its shape, and store without spoiling.
The drying unit is separated in three different areas. It starts with pre dryer then goes to first degree drying
area and finally to the second degree drying area. Drying temperature and relative humidity increments are
important factors in drying.
ABCDEFG-
PREDRYER UNIT
1st DEGREE DRYING UNIT
2nd DEGREE DRYING UNIT
CONNECTION UNIT
COOLING UNIT
GENERAL DRIVE
STICK RETURN DRIVE
FIG. DRYING AND COOLING UNITS
After the drying the dried pasta has to cool down to get it packed. The curtain has to pass the connection
unit to get to the cooling area.
The drying and cooling mechanisms installed in this machine has a set of centrifugal fans, radiators and
baffles with hot or cold water supply for heating and cooling purposes. The hot water came at 120 ˚c and
returns at 110 ˚c heating the radiator. The centrifugal fans then spread the air causing hot air around the
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area. the baffles are a cliff like structure sticking to the ground causing air circulation and even air
distribution around the area. Cooling goes same process the heating is just changed with cooling the air.
Each drying and cooling unit have 5 of their own radiator sets.
Pre drier
Pre drying hardens the outside surface of the pasta while keeping the inside soft and plastic. Since the
outside surface of the pasta dries more rapidly than the inside, moisture gradients develop across
the surface to the interior of the pasta. Although, if dried too quickly, the pasta will crack, giving the product
a poor appearance and very low mechanical strength. So it’s important to make sure the temperature do
exactly what had to be done and facilitate the second process.
1st degree drying
This unit provide a settling temperature and humidity to spread the moisture from inside to the outside
evenly. The pre drying made the pasta dry only at the outside. So the water inside had to get out without
any quality loss and the only way to do that is by settling the pasta curtain for certain time to get spread.
In other words, drying temperature has to be avoiding surface pasta drying and the consequent closing of
the interstices through which the remaining water can reach the surface by capillarity and evaporate.
Although, If the pasta is dried too slowly, it tends to spoil or become moldy during the drying process.
Therefor the settling had to be done at precise duration and exact temperature humidity values.
2nd degree drying
The pasta is now ready to get to the desired moisture level. The water inside is out in the surface and at this
stage by heating the surface, the pasta curtain will reach moisture content of 13- 15%. This unit apply the
last drying process the pasta will be then ready to be cooled.
Cooling unit
After the drying operation the pasta has to be cool down to a room temperature to be packed. Cold water
creates a cold environment around the unit and it is spread around by the fan for several minutes and will
be transferred to the cutting and packing area. During cooling phase, the moisture content of the product
falls from 11.1-13.2% to 10-12.5%.
Packaging
After cooling the pasta is unloaded the belts of the stripping saw unit. At this unit there will be an operator
to observe and analyze the quality of the pasta. The pasta will be entering the striping saw through number
in the figure below and the stick will slide through at and the pasta get unloaded on the belt at. The belt has
two-way movement. According to the quality analyzed by the operator, it passes to the left as a whole
product with less level of standard or to the right cutter. The cutter slices the pasta in 2 halves and has 3
blades. One to cut the upper tip, one to cut the bottom tip, and one to slice it half way. The small tip fractions
will be collected at the bottom of the cutter. And the pasta slide through the right and will be collected by
the bucket elevator and will be unloaded to the packaging machine.
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Fig. stripping saw
Fig. packaging machine
The packaging machine have a weighing and scaling devices installed in it. And the pasta will be weighed
and push through a cylindrical tube which have a sealing film. And the pasta in the sealing film will roll
pass the air supported hot blade cutter. It is a continuous and chain process. The pasta product will be then
packed and be transferred in to immediate storage.
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2.3 Short cut pasta (macaroni) processing
2.3.1 Introduction
Macaroni is a type of pasta product with variety of shapes and shorter length. The smaller size
property makes it easier to process than long cut pasta. Drying takes less time and any kind of miss treatment
or abnormal value change (like temperature and humidity) cause less product quality defect than it will do
to long cut pasta. The flour used is also semolina but with less gluten content than it is used in long pasta.
Production of macaroni in the company applied in three different shape of macaroni product. These
are spiral, big elbow, and, small elbow macaroni. The differences of these three macaroni products are only
by the shape of the macaroni.
2.3.2 Ingredients
The raw materials used for production of macaroni include water and semolina flour. The only
difference between the pasta flour and this flour is, the quality. The pasta requires higher gluten content due
to the influence of its physical characteristics and other factors. But macaroni is short and usually thick
which makes it more resistant to cracks and discoloration.
2.3.3 Process description
It has a flour dosing system and a water dosing system similar to the long pasta process line. Although, It
doesn’t have a scrap recovery and use different pre drier unlike the pasta line. It has a simple process.
Flour dosing unit – is a unit which is responsible for the flour quantity that will be introduced to the pre
mixer. It is exactly the same as the one used for pasta processing.
Water dosing unit – is generally a water pumping equipment which has a thermometer pressure gage and
flow meter controllers to dose and control the water flow.
Pre-mixer – is a mixer which water and flow will be blended. It has a conveyer to put the water through
the flour and facilitate the next process which is thoroughly mixing.
Mixing through tank – is a mixing tank with two mixing shafts rotating in opposite direction and a
vacuum system similar to the one used for pasta processing. The mixing through tank will homogenize the
dough and send it to the extrusion group.
Extrusion group
The hydrated semolina is conveyed from the screw into the extrusion barrel to be compacted. Pressure
increases from approximately 0 to 2 MPa to help transform the hydrated granular semolina into a compacted
dough. During compaction, temperature also increases due to friction between the dough, screw, and walls
of the barrel. The friction is necessary to compress the dough and move it down the channel. The excess
heat is removed by a warm water jacket that engulfs the extrusion barrel, which keeps the temperature of
the dough and barrel at approximately 45°C.
The ideal temperature for pasta extrusion is between 45°C and 50°C, as anything above 50°C will denature
the proteins and impede in gluten matrix formation. As a result, a soft sticky product is produced. Using a
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cold water jacket, as opposed to a warm one, will cool the dough and barrel too quickly and result in
undesirable dough viscosity. After the dough has been compacted it continues to move along the extrusion
screw, where it kneads by flowing forward and getting pushed back by pressure forces. The gluten
molecules in the dough are stretched and aligned with the directional movement of the screw.
After getting out of the extrusion barrel, the kneaded dough will inter the circular head that have a filter,
die and pre die. Before dyeing or shaping processes the impurity present in the dough is filtered by filter or
screening equipment. After screening the dough pass through pre die. This pre die used to create a favorable
shaping condition to the next die or shaping process. The dough finally passes through the die which gives
a particular shape for the dough.
Fig. macaroni die
After passing through the die and have a particular shape, it ‘ll pushed by a hot air ventilation to prevent
sticking and will be thrown to a pre drier called shaker.
Pre drying – the machine specifically used for macaroni pre drying is called a shaker. The macaroni is
spread by the hot air fan in the shaker and the shaker uses vibration to prevent the macaroni pieces from
sticking together. The shaker reduces the moisture of the macaroni by up to 17%. This will make the surface
dry. Then the bucket elevator receives the pre-dried macaroni and place it to the top of the drier.
Drier - The drier have 9 tires and the drying process takes place from the top down to the bottom. The
series of tire movement set up in the opposite direction. The mechanism of drying is the same as the pasta
line. The macaroni will be out of the drier in the bottom and enters the cooling system.
Cooler- the cooler system uses 3 air fans with an open air surrounding. The macaroni passes through the
fans which makes it cool and dry and ready to be packed
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Fig. cooling machine
Packaging- the macaroni then will be weighed and packed according to demand. There is a 25 kg
packaging material also there is 250 g packaging material. Then the packed product will be stored and
ready for sell.
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Chapter 3
3. Quality control and basic water and air supply units
3.1.
Quality control analysis
Quality control is a system for verifying and maintaining a desired level of quality in an existing
product by careful planning, use of proper equipment, continued inspection, and corrective action as
required. And also in other expression quality control is a process employed to ensure a certain level of
quality in a product or service. The major goal of quality control is to ensure that the product, services,
process provided meet specific requirement and are dependable satisfactory. Essentially quality control
involves the examination of a product or process for certain minimum levels of quality.
The aim of quality control is
•
•
•
•
•
•
•
•
To ensure the quality of the food product.
To protect the customers or clients from chemical, biological, and physical contamination of
foods or injuries.
To create peaceful method of production.
To ensure the productivity of the food product.
To create favorable condition for production of food product.
To ensure commercial competitiveness by producing safe, nutritious and quality of food.
To improve nutritional value of the food.
To ensure the quality of food product by assessing, controlling, and monitoring
different law of the food product.
3.1.1. Quality analysis of raw wheat
Wheat needs to be graded to make sure the company buy the right type of raw material for fair
price. At the same time the wheat will be determined as its quality. It is on this unit’s hand to determine the
right quality which makes it very essential for the entire processes in the company.
The quality of wheat will be determined in the following procedures.
Moisture content determination
The first step of determining the quality of wheat is determining its moisture content. It is applied by low
temperature heating to determine the moisture loss. It will be ground first and the following methods took
place.
Method
-
2-3 grams of flour is weighed and placed in a moisture dish
Sample is heated to 266˚f in an air oven for one hour.
Sample is cooled to room temperature and the residue is weighed.
Results
-
Moisture content is determined by comparing the weight of the sample before and after heating.
The amount of weight loss is the moisture content.
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This amount is expressed as a percentage. For example, moisture content above 14.5 % is
unacceptable.
The importance of this procedure is the information in this test is often used as a basis for other tests. Wheat
flour is often required to have a unified moisture content in subsequent tests. Wheat with a high moisture
content (over 14.5%) attracts mold, bacteria, and insects, all of which cause deterioration during storage.
Hectoliter weight
This method is used to determine the hardness od the wheat.
Method
The wheat is placed in a cylinder with 250 ml volume and weighed and the hector liter weight will be
determined by the following formula.
ℎ ℎ
0.0025 ℎ
ℎ =
ℎ
Result
The wheat will be failed if the hectoliter weight measure shows less than 73 kg/hl.
grade
Kg/hl
bread
73.2 – 74.8
macaroni
75.2 – 79.6
Pasta
80.0 and above
Table. Standard for wheat based on hector liter weight in AFRICA PLC.
Impurity
The raw wheat sample will be weighed in a small amount and the impurities in it will be separated. After
that the pure sample will be measured and the difference is the impurity and will be put in %. Impurity of
wheat which have a value of > 7% will be failed.
Protein (gluten) content
Protein is related to many processing properties, such as water absorption and gluten strength. Gluten
strength can be related to finished product attributes, such as texture and appearance. High protein content
is desired for pasta production.
Method
-
60 grams of sample wheat flour will be mixed with 10ml of 4% sodium chloride solution
It is then kneaded well and let it develop for 15 min
After 15 min the starch is washed away using running water
and after the starch completely removed, the dough remain will be dried by using clean cotton
then it will be weighed and the difference will be put in %.
Result
Gluten content less than 23% will be avoided. The following are the standards used in AFRICA PLC.
Grade
Gluten content in %
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Pasta
Macaroni
Bread
Table. Standard based on gluten content
INTERNSHIP REPORT
27 – 32 %
25 – 32 %
23- 25 %
3.1.2. Production line and final product quality analysis in pasta &macaroni line
In Africa plc., the quality analysis of every process level of pasta and macaroni line will be checked every
2 hrs. to make sure everything goes as it is supposed to. In line inspection mainly concerned with moisture
content. The samples will be taken from pre-drier, drier and after cooling.
The final product analysis concerned with weight of the packed products and inspection of physical
characteristics and grading accordingly.
3.2. Water and air supply room
These area is responsible for every water supply for mixing cooling and heating processes, and also
responsible for air supply for pneumatic valves and air supported systems.
Boiler
It is a machine which uses fuel to heat up water at 120 ˚c. At this stage the water is at a boiling point but
the pressure applied by the boiler keep it at a liquid stage to circulate.
Fig. boilers
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The hot water will be circulated by the electric pumps in to the drying process of pasta and macaroni
processing plant.
Fig. hot and called water supply pumps(left) , backup water tanks(right)
Chiller - It is the cold water supply for the pasta production unit and also for cooling system in the
extrusion barrel.
Air compressor – it compresses the atmospheric air around it and supply the whole processing lines air
pressure need.
Fig. air compressor (left), chiller (right)
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Water treatment
The water that brings in the pasta and macaroni nutrients is altered here by the water treatment machine.
Simply it influences the quality the final product directly.
Fig. water treatment equipment
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Chapter 4
4. Over all benefits
4.1. Improving Practical skill
Practical activities are very important in the learning process. It will help the student to get an understanding
of the outside working world. My internship period at Africa plc., thought me different kinds of practical
skills. The process of wheat production has a very lots of machines with different working principles. The
practical activity I implemented in there help me to understand the theory with practical skill. It really feels
good to be able to do what you know on paper. And most of all, to know the value of what I have learnt in
school. It is wonderful and motivating.
4.2. Update theoretical knowledge
Theoretically, the milling process and the pasta production process were covered in one course which is
cereal and pulse technology which has a laboratory practices. Clearly theoretically there was a slight
weakness on my knowledge in that area. But I was fascinated when I saw how the laboratory is done which
is exactly the same as we have practiced in here. It made it easy for me to coupe up with the practice soon
enough. I would like to appreciate our departments laboratory personnel and I wish it continue with better
equipment facilities because I understand now how important it is. But the theoretical part I had to go
through different manuals and working principle describing books to upgrade my knowledge. The
mechanical aspect of the process was entirely new to me so I found my way there.
4.3. Improving interpersonal communication skills
It is a skill to be able to communicate well with the people in the working environment. I was not easy
going in my personal life so it made it a little bit of difficult for me to communicate in the first couple of
days. But then I get along with every one and get the information flow going. I have understood the
importance of good communication with co-workers and good connection working environment. It is very
essential for productivity in the working area. I can say I have learnt that during my time in Africa plc.
4.4. Work ethics
Work ethics built internal moral and codes of ethics of employees. Morality and ethics usually represent
the personal beliefs of individuals display when working in business. In my hosting company I believe I
gained the following aspects of work ethics. Transparency, good relationship with work colleagues based
on mutual respect, responsibility on gathering analyzing and interpreting data, punctuality.
4.5. Entrepreneurship
It is a skill to create something new. To be able to do that, one has to have at least the following skills.
Self-motivationThe most important skill any entrepreneur needs is the ability to wake up in the morning and begin working.
Not only do i need to be able to wake-up, but I also need to be able to begin and end work on time. I believe
my time in Africa plc helped me gain that motivational skill.
Self confidence
Every entrepreneur needs to be confident in themselves, their product and their business. I need to know
that my product can truly help people. By achieving this internship well enough, I have developed a good
self confidence that I can achieve anything that I desire to do.
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Chapter 5
5. Conclusion and recommendation
5.1. conclusion
Africa plc is a food manufacturing company mainly with the products of pasta, wheat flour and,
macaroni in Oromia region specially covered Adama town. The average design annual production
capacity for Wheat flour 1200 Qtl/ hr. Pasta 2500 kg /hr., Macaroni 2400 kg/ hr. and Bran / for
animal feed/ 324kg/ hr. Currently Africa plc produced about 5 different shapes of Pasta and
Macaroni. The company pasta products are namely Buona, Roma and Rosa. In Macaroni product
BOUNA, AFRICA and Wheat flour is another product of the company. And also the company is
ISO 22000:2005 certified and following HACCP requirements.
I have managed to get involved in the laboratory which the first assessment of raw material and
grading and also the production line quality assessments are done. I worked through production
steps of wheat flour production, pasta production and macaroni production process steps. It has
been a wonderful experience. During my time, I get different theoretical knowledge and practical
skill with good experiences and benefits.
•
Raw material before purchase, it has to be analyzed to determine the grade and quality of
the raw material. In laboratory, determination of moisture content, hectoliter weight,
hardness, impurity, gluten content will be checked. The laboratory grades the quality of
the wheat and assists the purchasing stuff so that they could determine the price. After
purchase the vehicle will be weighed on the way in and on the way out after unloading.
They use the difference to determine the amount in tones. And it will be sorted and stored
in the store.
•
The milling process includes pre cleaning, cleaning, conditioning, milling, sifting, and
packaging. It is a very complex and interesting process. I enjoyed my time learning
executing it.
•
Pasta and macaroni production involve the processes of premixing, mixing through,
extrusion, pre-drying, drying, cooling and packaging. It is a process that needs a careful
configuration of temperature and humidity. The quality of durum semolina wheat is very
essential since the gluten content is what it gives it the firm structure.
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5.2. Recommendation
I would like to recommend to the hosting company some points that I have observed during the
time of my internship stay.
•
During unloading the purchased wheat, there are a lots of wheat leakage because of the
sample taking method the damage to the bags makes large amount of leaks on the ground.
Even though it is collected and reintroduced there is unnecessary loss of quality row
material since it will only be used for low quality flour. And it is exposed to starch damage
which again reduces the quality of the wheat.
•
There are birds in the facility of wheat production and also in the pasta manufacturing
plant. They are pretty much ignored by everybody. They are active in the areas where the
product is open to the air which can be a point to introduction of contamination.
•
The pasta recovery machine malfunctions sometimes. And when it does there will be huge
loss of recoverable pasta. Even though it is used for feed of animals, it can be added to the
whole production by simple handling and sanitation activities. At the same time, sanitation
wise, the personnel in that working area take care of the problem by throwing the pasta to
the ground and using un sanitized bags which is very bad for the quality. And re-introduced
in to the mixer. The understanding in there is contamination is impossible due to high
drying temperature and low moisture content in the process and physical hazard can be
eliminated by filters, although this excuse did not consider the chemical hazardous
contaminants and the drying temperature is not more than 90 ˚c which is not pasteurization
temperature. This means spores of micro-organisms will not be removed and can survive
the process which makes the product not safe for use. This treat can easily have controlled
by the sanitation of personnel and handling equipment.
I find it essential to give recommendation to the department of food technology and process
engineering. We have learnt a lot of food processing industry processes but we do not get the
chance to see half of what we learnt in practice. Students in our level in other universities have
had a lot of this on field experience. And when we go out graduating, we all know what we are
competing against. So I recommend that the department should see this field experiences as
essential as class room education otherwise it will keep producing low quality students to the
working environment and I don’t think that’s the aim of the school.
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Reference
•
•
•
•
•
Africa private limited company HACCP manual document
Africa private limited company quality control working manual
google.com
Skills you need.com
Manual of milling and pasta
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Appendix
•
•
•
•
•
HACCP
Hazard analysis critical control point
ISO
International standardization organization
ISO 22000:2005
Food safety management system
plc
private limited company
W.F.R
water flow rate
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