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1
Submitted By:
ASIM SHABIR
B.Sc. (Hons.) Food Science and Technology
National Institute of Food Science & Technology
University of Agriculture Faisalabad-Pakistan
2
ACKNOWLEDGEMENT
All thanks are duly to almighty ALLAH, the most Gracious and the most
merciful who enabled us to complete this report. First of all we wish to express
our profound gratitude to our loving Parents who enable us to come up to the
challenges with their blended love and affection from the cradle of childhood to
prime of youth who made every possible effort to make us available the best
career opportunities so that we could lead a prosperous life. We salute our parents
for making every possible effort to provide us best career.
Secondly all our teachers deserve a lot of credit for successful
accomplishment of this report including those who patted and encouraged us
during our schooling. On the successful completion of this report we will like to
acknowledge our cordial gratitude and thanks to MUHAMMAD AMIN CHISHTI
(GENERAL MANAGER) and SHAHID IQBAL (ASSISTANT PRODUCTION
MANAGER) and all other employees MADNI GHEE MILLS (PVT) LTD. for
their continuous and praise worthy guidance and help throughout the internship.
MAY ALLAH BLESS THEM ALL!
Regards:
ASIM SHABIR
B.SC. (HONS.) FOOD SCIENCE AND TECHNOLOGY
NATIONAL INSITITUE OF FOOD SCIENCE AND TECNOLOGY
UNIVERSITY OF AGRICULTURE FAISALABAD
3
CONTENTS
Chapter Title Page 1 INTRODUCTION
a. Brands b. Set up of industry c. Policies of Madni Ghee Mills
I. Quality and consumer safety policy II. Environmental safety policy
7-10
2 REFINING PROCESSING I. GENERAL PROCESSING OF OIL
II. GENERAL PROCESSING OF GHEE a. Pre-Neutralization b. Pre-Bleaching c. Hydrogenation d. Post-Neutralization e. Post-Bleaching f. Deodorization g. Blending of vitamins h. Packaging i. Chilling
11-20
3 SOAP SECTION 20-21 4 CRUDE OIL AND REFINED OIL TEST
1) FFA test 2) Color test 3) Moisture determination 4) Mineral oil test 5) Rancidity test 6) Soap test 7) Peroxide value test 8) Vitamins test 9) Refractive index 10) Saponification value 11) Iodine value 12) General appearance 13) Smell 14) Melting point 15) Cloud point
22-32
5 SOLUTION PREPARATION a. Starch indicator solution b. Potassium–iodine solution c. Phenolphthalein indicator solution d. Ascetic chloroform solution e. Sodium hydroxide solution f. Sodium thiosulphate solution g. Potassium-hydrogen phthalate solution
33-39
6 CONCLUSION 37 7 REFRENCE 38
4
1. INTRODUCTION
Madni oil industry is situated 32 Km Sheikpura road. It is reputed and
leading name in vegetable ghee, cooking oil and soap products comprised upon
following processes within existing premises:-
1. Vegetable ghee
2. Cooking oil
3. Tin packaging and printing
4. Laundry and Toilet soap
Madni Ghee Mills (Pvt.) Limited having production capacity of vegetable
ghee as 24000 Metric Ton, cooking oil 20000 Metric Ton and laundry soap 24000
Metric Ton on per annum. Its products are registered with defense forces, utility
stores corporation and canteen stores department of defense forces. Where its
supplies are successfully being supplied and many contracts of vegetable ghee,
cooking oil and laundry soaps have already been successfully completed and few
in pipelines. The unit is registered with Pakistan Vanaspati Ghee Manufacturing
Association, Chamber of Commerce and industry, Sales Tax Department
Government of Pakistan, Pakistan Army, Navy and Trade Marks Government of
Pakistan.
Technical staff of Madni Ghee Mills (Pvt.) limited is highly experienced
and well educated in this field. The unit comprised upon 74 Kanal 04 Marla’s and
165 sq. ft of land, which is equipped with unique type of latest machinery and
plant installed in its attractive building. The beautiful roadside Mosque, fruity
garden on the front side of the office block creates extra ordinary beauty. Private
energy source, Gas connection and sewerage line linked with disposal drain are in
existence within premises of the mills.
The people who are dealing in vegetable ghee, cooking oil and laundry
soap they know well the name of madni ghee mills renowned products, which are
in the market with the name and style of “Madni banaspati, Madni cooking oil and
Madni laundry soap.
5
a. BRANDS:
Pakwan cooking oil
Madni cooking oil
Madni banaspati
b. SET-UP OF INDUSTRY
Administration block
Oil refinery
Neutralizers
Bleachers
Deodorizers
Autoclaves
Filter press
Coolers
Hydrogenation plant
Quality assurance lab
Steam boiler unit
Soap preparation plant
Filling unit
Work shop
Tin printing unit
Raw oil storage tank
Water storage tank
Caustic soda tank
Centrifugal pumps
Note:
Boiler
There are two Boilers with a capacity of 250 Pounds each. The
Boilers are wet heat energy source in the form of steam. This heat
circulates in all the heating coils of processing units. Its input is water
treated with softening chemicals (NaCl, Aqua Prime) and output is heat
energy in the form of steam. The maximum temperature is 205OC.
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Gas Cracking Plant
The requirement of Hydrogen (H2) Gas is met through the production of
gas by the Gas Cracking Plant using Natural Gas as raw material by cracking
Methane (CH4). CO 2 is the bye-product.
Receiving And Storage Of Raw Oil
The raw oil is imported from Malaysia, Indonesia, America and Brazil. It
is transported to the factory through lorry tankers and is stored in storage tanks.
Usually Cottonseed oil, Canola oil, Sunflower oil, Soybean oil and R.B.D. Palm
oil are used for manufacturing of ghee.
c. POLICIES OF MADNI GHEE MILLS (Pvt) LIMITED
i. Quality and consumer safety policy
Madni ghee mills take care to ensure that their customers & consumers are
provided with the best quality products that are safe in use. To meet the
customer’s expectation and needs. Madni ghee mills is committed to develop and
ensure consistent supply of affordable, convenient, safe and high quality products.
As a service company we take care to ensure that our customers are provided with
the best quality services to fulfill all customers needs.
In order to achieve these goals Madni ghee mills will:
Agree quality and consumer safety objectives along with
implementation plans on annual basis and maintain follow up by
reporting process
Design operate & maintain processes and plants to establish and
maintain standards and procedures for the control and
monitoring of all operations that prevent potential product safety
hazards.
Will ensure the compliance with applicable legislation and set
standards
Introduce appropriate product quality management system &
maintain HACCAP as a management tool at all their operating
sides
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Help their suppliers to develop their quality process & standard
so as to get consistent quality suppliers and develop supply chain
to improve overall quality performance audits
Responsibility to implement this policy lies with general
manager & the same is filtered to the functional heads and
respective managers in their areas of responsibility
ii. Environmental Policy
Madni ghee mills are committed to meet the needs for customers
and society in a sound environment and sustainable manner
Work in co-operation with members of industry, government
bodies and public interest groups, scientists, environmentalists,
technical department and customers to promote achievements of
high standards of environmental care
Continuously strive to reduce the wastage, conserve energy,
examine reuse & recycle throughout operation being carried out
at Madni ghee mills
Ensure all the employees are the aware of the company
environmental policy and are motivated to apply it
Ensure the safety of our product manufacture at our side & will
continue monitor and report all progress & notify environmental
incident on regular basis
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2. REFINING
Refining of vegetable oils in simple terms means “Removal of
Impurities”. Major impurities in the oils may be enumerated as follows:
Dirt and other foreign matters to the seeds
Solid matters from the seeds
Mucilage
Free fatty acids
Coloring matters
Substances imparting taste and smell to the oil
Moisture
Refining eliminates all the impurities. The process employed in refining is
comparatively simple. If the raw material from which oil is extracted is clean, dry
and sound the oil produced is of good quality while oil obtained from inferior,
unsound oil seeds contain more impurities. The processes employed in refining
are either mechanical, chemical, or combination of two. Following steps are
involved in manufacturing of cooking oil and vegetable ghee:
I. GENERAL PROCESSING STEPS OF OIL
PREPARATION
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II. GENERAL PROCESSING STEPS OF VEGETABLE
GHEE
a. PRE-NEUTRALIZATION
Pre-neutralization is carried out in a vessel called pre-neutralizer. It is
cylindrical in shape and has electric motor for centrifugation of oil. Motor has
steering shaft with baffles for complete mixing of contents. It has steam heating
coils and caustic soda washing coils. Temperature gauge is also mounted on it.
Generally the process of pre-neutralization is completed in 7-8 hours.
The objective of pre-neutralization is the removal of free fatty acids. Oils
have 2-2.5% free fatty acids. It has to be reduce it to 1-1.5%. PSI (Pakistan
Standard Institute) recommends 0.20 - 0.25% free fatty acids. Due to removal of
F.F.A. the color of oil is improved. Usual method of removing the free fatty acids
is to treat the crude oil with Sodium hydroxide solution carefully regulated in
strength and amount, and at carefully regulated temperature. Firstly free fatty acid
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percentage of crude oil is determined and then NaOH of required Baume is added.
Generally NaOH of 20-22 Baume is used. Then crude oil is charged in to the pre-
neutralizer and it is centrifugally moved with the help of electric motor. The
temperature of oil is raised up to 70oC with the help of steam heating coils. When
required temperature is achieved NaOH of 20 - 22 Baume having 70oC
temperature is added to crude oil with the help of caustic soda washing coils, it is
thoroughly mixed for 10-15 minutes. The soda solution combined with the free
acids turned of soap. After this it is given one-hour rest. During rest soap settles in
the bottom and oil becomes on upper side. The soap is drained through the drain
valve mounted at the bottom of vessel. Then the oil is washed with water having
100oC temperature. Water dissolves soap and free alkali and settle down oil comes
on upper side. It is given 1-hour rest and the water is drained through drain valve.
Oil sample is taken to check free fatty acid percentage up to 0.25% or less.
Soapy particles should not be present. If soapy particles are present then oil, again
washed with water and given 1 hour rest. The number of water washing depends
upon nature of oil e.g. cotton seed and soybean require three washer, canola
requires two washer. Pre-neutralized oil has 0.25% or less F.F.A.%. Madni
Banaspati has 0.08% F.F.A.
Following tests are applied at pre-neutralization stage:
F.F.A % test prior to processing
F.F.A % test after processing
Soap test
Note: The pre-neutralized oil is then passed to pre-bleacher for bleaching.
Amount of caustic soda required to neutralize free fatty acids is 9 Kg of solid
NaOH. It is required to neutralize 0.4% F.F.A in a Batch of 16 tons.
b. PRE-BLEACHING
Pre-bleaching is carried out in a vessel called pre-bleacher. It is cylindrical
in shape and vertical in direction. It has an electric motor having steering shaft
with baffles for centrifugation of pre-neutralized oil. It has temperature gauge,
vacuum gauge , pressure gauge and steam heating coils for raising temperature of
input oil. Generally the process of pre-bleaching is completed in 3-4 hours.
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The objective of pre-bleaching is to get rid of unwanted pigments and
coloring matters from input oil. Bleaching is done by means of bleaching earth
(Clay+silica dioxide, mixed in certain proportion and ground to particle size of
250 micron and acidified with HCl). It contains 3-4% moisture known as Fuller’s
earth. First pre-neutralized oil is charged in to the bleaching vessel and stirring is
started. Then it is warmed and dehydrated under vacuum at 120 oC to remove
water and free air. It takes 1-2 hours for complete dehydration. After this the oil is
cooled to lower down its temperature up to 110 oC. Then take in the bleaching
earth at recommended rate depending upon the intensity of color of oil as below is
carried out.
Note:
Palm and palmoline = 2Kg / ton of oil.
Soybean and canola = 5Kg / ton of oil.
Cotton seed = 8Kg / ton of oil.
The amount of bleaching earth is doubled in case of cooking oil. 75% of
bleaching earth is added in pre-bleacher & rest of 25% is added in post-bleacher.
The process consists of thoroughly stirring the dry absorbent powder into the oil
when gently heated under vacuum status. Activated carbon at the rate of 100 g/ton
is also added in case of cottonseed oil, to bleach the darker color of cottonseed oil.
Fuller's earth is mixed slowly so that every particle of the oil combines with every
particle of the earth. Stirring continues and that the whole process takes about an
hour. Fuller’s earth removes all the impurities and color, and makes the oil fine. It
also absorbs any particle of soap that is left behind. Explanation of the matter lies
in the fact that the coloring substances, which pass from the seed into oil, is
absorbed and held back by earth. Maintaining the input oil temperature at 100oC
05 oC. Bleached Oil is filtered the through filter press. It removes the bleaching
earth and clear oil is obtained. The color index of bleached oil is measured with
the help of spectrophotometer / tintometer.
Following tests are applied at this stage:
Color index R,Y
F.F.A %
The pre-bleached oil is then passed to converter for hydrogenation.
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c. HYDROGENATION
Hydrogenation or hardening may be defined as a process whereby part or
in some cases nearly all the unsaturated acids in an oil are caused to combine
with hydrogen under the influence of a catalyst. In this way the glycerides of the
unsaturated acids are converted into the saturated acids of another series. Thus in
case of olein which is unsaturated, the addition of 6 atoms of hydrogen produces
stearin, which is saturated in accordance with the following formula:
(C17H33COO)3C3H5+3H2 Ni/Pt , H (C17H35CO3O)C3H5
Olein (unsaturated) Stearin (saturated)
Out of the many processes, which has been suggested with the objective of
converting liquid oils into solid fats, hydrogenation is the only one, which has
been applied on large commercial scale. When it is considered that only 0.68% of
H2 by weight is necessary to convert olein into stearin and how great is the change
brought about in a simple manner by so small addition. By volume 30 feet3 of
hydrogen is required for each percent reduction in iodine value of per ton of oil.
Hydrogenation is carried out in a vessel called converter or autoclave. It is
completely airtight vessel and has heating coils, steering shaft having baffles,
perforated hydrogen coils, compound gauge to measure pressure and vacuum and
temperature gauge to measure temperature. Generally the process of
hydrogenation is completed in 6-8 hours.
First the vessel is filled with neutralized and bleached oil. It is dehydrate it
up to 170o C temperature under vacuum for 1-½ to 2 hours. If water is present then
it will poison nickel and which effect its quality. After this hydrogen gas is
applied through perforated hydrogen coils under vacuum and thoroughly mixed
by continues stirring. Now food grade Nickle catalyst (G-53, Germany) is added
in recommended quantity as follow:
100 grams/ton for palm oil
13
250 grams/ton for soybean oil
200 grams/ton for sunflower & cottonseed oil
Hydrogen gas is applied continuously and samples are drawn for the
inspection and testing of melting point. Desired/approved/recommended melting
point for Banaspati ghee is 36 2 oC. When approved melting point is achieved
then hydrogen gas is stopped. After this, the converted product is cooled up to
100-110oC. Then product is filtered through filter press. It removes Ni catalyst
and clean, clear oil is obtained. The product may not be cooled below 90oC
otherwise it will create problem in filtration. Again melting point is verified after
filtration. Hydrogenation is not carried out in manufacturing of cooking oil.
The extent to which an oil has been hydrogenated, is measured by the fall
in iodine value, which the oil has undergone, since it is directly proportional to the
amount of hydrogen gas, which has been added to the oil. F.F.A% increases
during hydrogenation. As hydrogenation proceeds and the unsaturated bodies
become saturated, the fall in iodine value is coincident with a steady fall in
refractive index and rise in melting and solidifying points.
This can be verified as:
Iodine value of cotton seed oil at charging = 140.2
Iodine value of cotton seed oil before gas passing = 95.8
Iodine value of cotton seed oil after complete hydrogenation = 71.69
Following tests are applied at this stage:
Melting point
Color index Red, Yellow
F.F.A % age
Iodine value
The hard oil is then passed to post-neutralizer for post-neutralization.
d. POST-NEUTRALIZATION
Post-neutralization is carried out to remove the soap and Ni catalyst if it is
present due to poor filtration. Firstly hard oil is charged into post-neutralizer. The
temperature of hard oil is maintained at 90 5oC by heating or cooling. Its free
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fatty acid % age is calculated and caustic soda is added accordingly. Generally
caustic soda of 8-10 Baume is added without any agitation, light wash of water is
given. After this 2 hour rest is given, due to rest soap settles down at the bottom
and oil becomes on upper surface. The soap is drained through the drain valve
present at the bottom of vessel.
Now two washes of boiled water are given. After 1st wash give 1 hour rest,
drain soap and water through drain valve. Then 2nd wash is given and same
process is repeated. Apply soap test, it should be negative. If it is positive then 3rd
wash is given. Generally the process is completed in 5-6 hours.
Following tests are applied at this stage:
F.F.A %age prior to neutralization
F.F.A %age after neutralization
Soap test.
The pre-neutralized oil is then passed to pos-bleacher for bleaching.
e. POST-BLEACHING
Post-bleaching is carried out in a vessel similar to that used for pre-
bleaching. First post-neutralized oil is charged into post-bleacher and its
temperature is raised up to 110 oC. It is completely dehydrated under vacuum and
stirring is continued throughout the process. When complete dehydration is
achieved then bleaching earth is added in recommended quantity. It is thoroughly
mixed in oil for 45 minutes. At the end post-bleached oil is filtered through filter
press to remove the bleaching agent from oil. Generally the process is completed
in 3-4 hours.
Following tests are applied at this stage:
Color index R,Y
Melting point
F.F.A % age
The post-bleached oil is then passed to deodorizer for deodorization.
f. DEODORIZATION
Deodorization is carried out in cylindrical vessel. It is completely air tight
and vertical in direction. It has open steam lines, steam heating coils and low and
high vacuum system. Steam pressure, temperature and vacuum gauges are
15
mounted on it. Electric motor with steering shaft having baffles is not present. A
fat catcher is present to catch volatile matters. Generally the process is completed
in 7-8 hours.
Deodorization is a process of steam distillation whereby relatively volatile
odoriferous and flavored substances are stripped from the relatively nonvolatile
oil. The operation is carried out at a high temperature to increase the volatility of
the odoriferous components. The application of reduced pressure during operation
protects the hot oil from atmospheric oxidation, prevents undue hydrolysis of oil
by steam and greatly reduces the quantity of steam required. The objective of
deodorization is removal of unwanted odors, odoriferous matters and other
volatile fatty materials and to improve smell, odor and taste of finished product.
Some of compounds responsible for tastes and odors of oil are ketones, terpenoids
and aldehydes. Flavor and odor removal generally parallels free fatty acid
removal. The concentration of odoriferous substances in oil is generally quite low.
In case of cottonseed, soybean, tallow and peanut oil, it does not appear to be
greater than 0.10%. Deodorization also reduces the color of oil and destroys
peroxides in oils. The process of deodorization is influenced by temperature,
vacuum, steam and design of deodorizer. Generally the process is completed in 8
hours in case of ghee and 12 hours in case of cooking oil.
Firstly post-bleached oil is charged into deodorizing vessel. Oil is warmed
and dehydrated up to 170oC under low vacuum status to remove moisture. When
the oil is completely dehydrated and required temperature is achieved, then the
process is boosted up to high vacuum status along with increase in temperature to
190 10oC. Now citric acid is added at the rate of 100grams/ton of oil. 50% of
citric acid is added before application of live steam and rest of 50% is added
before cooling. Citric acid helps in removal of volatile matters and increase shelf
life of final product. The process is assisted with treatment of oil with live steam
for 3-4 hours. Samples are drawn for sensory evaluation and tests are also applied
for justification of deodorization. When the product is free from bad odors the live
steam is stopped and product is cooled down up to 140 oC. Now it is shifted to
cooling vessel (cooler) for further lowering down of temperature to 70 oC. Cooling
16
is done under vacuum to avoid oxidation and to remove water. After this it is
filtered through filter press and passed to churns.
Following tests are applied at this stage:
General appearance.
Odor/smell
Taste
F.F.A. %age
Rancidity
Moisture
Soap test
Melting point
Peroxide value
Color index
Note:
In case of Cooking Oil Hydrogenation, Post Neutralization & Post Bleaching are
not performed.
g. BLENDING (addition of vitamin A&D3)
Completely deodorized product after filtration is taken into filling churns.
Here vitamin A&D3 are added in recommendedquantity/dose. Vitamins are
imported from Germany (Merck). (BASF).Generally 33 ml of vitamins/ ton of the
product are added and thoroughly mixed by continuous stirring. Samples are
drawn for vitamin confirmation test, the vitamin test should be +ive. Now it is
ready for filling and packaging.
h. FILLING/PACKAGING:
Product is cooled up to 50 5oC. Now it is
manually/mechanically/automatically filled in food grade approved packaging
material. Automatic filling is carried out in case of pouches. The Prepack Click 2
machine is used for automatic filling and it fills 2000pouch of 1.0 Kg size/hour
and 2400 pouch of ½ Kg /hour. After filling tins/buckets/pouches are properly
sealed. The products are packed into different pack mix for marketing as detailed
below:
Vegetable ghee
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16 Kg. Tin and Bucket
05 Kg. Tin and Bucket
2.5 Kg. Tin and Bucket
01 Kg. Pouch pack
½ Kg. Pouch pack
¼ Kg. Pouch pack
05 Kg. Pouch Pack
Cooking oil
16 Letters Tin
10 Letters Plastic Can
05 Letters Pet Bottle
05 Letters Pouch Pack
05 Letters Tin
2.5 Letters Tin
03 Letters Pet bottle
Letter Pouch pack
i. CHILLING
When a fat is allowed to cool slowly without any agitation, then it sets up
grain. After packaging ghee is gradually chilled in chilling rooms, which are made
of insulating material to maintain the temperature of chilling room. Ammonia
compressed air conditioning machine is used for this purpose.
The chilling process of vegetable ghee is completed in 18-22 hours in
summer& 8-10 hours in winter and temperature of 8-9oC is maintained in chilling
room. After chilling ghee is stored in ware houses at room temperature and is
ready for consumption.
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3. SOAP SECTION
There are 5 steps in soap manufacturing:-
1) SOAP GRAIN MIXING PAN:
It is cylindrical in shape, fitted with separate lines for induction of caustic
soda and water. Soapy matters are transferred in pan from neutralizer, cutting
wastes and fats from the deodorizers. After charging, H2O is added to convert it in
liquid form. After this caustic soda of 50 Baume in recommended quantity is
added, it is heated till the required texture is achieved, which almost depends upon
experience.
2) SOAP BOILING / BOILING AND MIXING PANS:
These are large pans and have capacity of 3 – 4 tons. In this soap is heated
for 7 – 8 hrs. Till water is evaporated and soap grains becomes smaller.
3) CRUTCHING AND MIXING TANK:
It is cylindrical in shape and has capacity of 5 tons. Soap is manually filled
in it with the help of tins from the boiling pans. After filling 60 to 75 kg of soap
stone mixed in 15 tons of oil is added. Sodium Silicate , 120 to 150 kg is added.
Subsequently, 2 tons of Resin are added. All the material is thoroughly mixed for
1 hour. It has baffles for mixing. Steam heating coils are present for heating. After
completion of the process one-hour rest is given to settle.
4) CONVERTION IN IRON FRAMES:
From crutching tank soap is filled into iron frames to convert it in blocks.
5) CUTTING AND PACKAGING:
Soap blocks are stored for 24 hrs. to reduce moisture. Cutting is carried
out with the cutters to convert the blocks in cakes of different sizes which are
packed in cartons of 9 kg capacity.
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4. EXPLANATION FOR CRUDE & REFINED
OIL TESTS
(AOAC (2000) Official Methods of Analysis. The Association of the Official Analytical Chemists, 17th ed, Arlington, USA.)
1) Free Fatty Acid Test
Both for crude & refined:
PRINCIPLE:
The fat is dissolved in appropriate solvent, after which the solution is titrate with
NaOH solution.
REAGENTS:
Ethyl alcohol, 0.1 N NaOH, Phenolphthalein.
EQUIPMENT:
Conical flask, Electric balance, Burette.
PROCEDURE:
Take 50 mL spirit in 250 mL conical flask.
Add few drops of indicator.
Neutralize with 0.1N NaOH till light pink color attain.
Add sample 5g for crude oil and 30g for refined oil.
Now titrate with 0.1 N NaOH till light red color attain.
Note the mL of NaOH used.
Calculated by given formula
FFA % age = mL of NaOH used × 28.2 × 0.1
Wt. of sample
For example:-
FFA % for crude corn oil:
FFA % age = mL of NaOH used × 28.2 × 0.1
Wt. of sample
= 10.3 × 28.2 × 0.1
5
= 5.06 %
20
FFA % for refined corn oil:
FFA %age = 0.7 × 28.2 × 0.1
20
= 0.08%
PSI Standers:
For corn crude oil FFA should not exceed 6% and for other edibles oil 0.39%.
According to PSI standard FFA for refined oil should not more than 0.24%.
% FFA REFINED OIL Oil T1 T2 T3 T4 T5
COTTONSEED 0.02 0.05 0.08 0.07 0.09 CANOLA 0.08 0.08 0.06 0107 0.05
SUNFLOWER 0.04 0.06 0.04 0.04 0.05 PALM OLEIN 0.07 0.02 0.06 0.02 0.08
(T=Test)
2) COLOR TEST
Both for crude & refined oil.
EQUIPMENT:
Tintometer:-
This method describe the colour by comparison with a trichromatic system of
yellow, red and blue filters.In practice, mainly red & yellow filters are used.
GLASS FOR INSTRUMENT:
Red
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
1 2 3 4 5 6 7 8 9
10 20 30 40 50
Yellow
1 2 3 4 5 6 7 8 9
10 20 30 40 50 60 70
Blue
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
1 2 3 4 5 6 7 8 9
For crude oil/ghee;
Check that windows of the measuring cell and filters are clean and
not covered with film of oil
21
Use one inch cell
Place the sample in cell and put in Tintometer
Adjust the red & yellow color in ratio 1:10 respectively.
Adjust the yellow color reading at 45 scale, should not exceed 50
Red color reading should not exceed 5.If greater it will reject
Observed reading for corn crude oil is 4.2 red
For refined oil/ghee;
Use 5.25 inches cell
Place the sample in it
Adjust the yellow color reading at 35 scale
Red color reading should not exceed 5
Observed reading for corn crude is 3.5 red
For example:-
Result for refied oil:
Red-2.9, Yellow-30
3) MOISTURE DETERMINATION
Both for crude & refined oil.
OVEN METHOD:
EQUIPMENT:
Beaker, Decicator, Weighing balance.
PROCEDURE:
Take empty beaker and weight it.
Than 20 g sample in it and weight
Now place it in an ovan for 1-2 hours at 110 0C
After that remove and place in desicator to retain temperature at
40 0C
Weight it again
Calculate the moisture by following formula
Moisture %age = Difference in weight ×100
Weight of original sample
22
PSI Standers:
For crude moisture limit should not be more than 0.2%.
For refined it should be 0%.
MOISTURE CONTENT % DURING PROCESSING OIL T1 T2 T3 T4
SUNFLOWER 0.23 0.16 0.02 0.0 CANOLA 0.20 0.15 0.01 0.0
CORN 0.21 0.17 0.03 0.0 PALM OLEIN 0.20 0.12 0.02 0.0
COTTONSEED 0.22 0.13 0.01 0.0
4) MINERAL OIL TEST
For crude oil
REAGENTS:
Alcoholic caustic potash solution 0.5 N, Distilled water
EQUIPMENT:
Conical flask, Condenser, Water bath, Hot plate, Weight balance
PROCEDURE:
Take 2 g oil sample in 150 mL conical flask which has been
previously dried thoroughly to ensure absence of water.
Add 25mL of alcoholic potash solution in conical flask.
Saponify the oil by keeping the flask fitted with glass-bulb air
condenser on a water bath for 45 minutes.
Care should be taken to ensure that saponification is completed
and also that there is no loss of alcohol during saponification.
Cool the flask and add 120mL distill water.
The development of turbidity indicates the presence of mineral
oil.
5) RANCIDITY TEST
For refined oil
REAGENTS:
Conc. HCl, Floroglucinol + ether solution.
23
EQUIPMENT:
Cylinder
PROCEDURE:
Take 10 mL of sample in cylinder.
Than add 10 mL ether solution in it and shake well.
If sample is rancid it will give red color the test is positive
otherwise negative.
6) SOAP TEST
For refined oil
REAGENTS:
Distill water, Phenolphthalene indicator.
EQUIPMENT:
Beaker, Hot plate.
PROCEDURE:
Take a beaker.
Add distill water plus phenolphthalene.
Heat it than add sample in it.
Oil will goes to top and water at the bottom.
If bottom is pink it means soap is present and if white it
means the soap is not present.
7) PEROXIDE VALUE TEST
For refined oil
This test is performed to check the oxidation.
PRINCIPLE:
Treatment of test portion,solved in a mixture of acetic acid and
dichloromethane with an aqueous solution of KI.Tritrate liberated iodide
with standardized solution of sodium thiosulphate solution.
REAGENTS:
Acetic acid + Chloroform solution, KI (saturated), Distill water, Starch indicator,
Na-thiosulphate.
24
EQUIPMENT:
Conical flask, Cylinder, Burette
PROCEDURE:
Take 10 g of sample in flask and add 60mL acetic solution +
chloroform solution (60% + 40%).
Than add 1 mL of potassium iodide solution (saturated solution).
After shaking it well put this flask in dark place for 5 minutes.
Now add 60 mL of distill water and shake it well.
Now add few drops of starch (indicator solution).
If the color of sample does not change POV consider to be nill.
If the color changes to dark than titrate it against 0.1 N solution
of Na-thiosulphate.
End point is white color.
Blank titration is also performed.
Calculated by given formula:
POV = mL of Na-thiosulphate used × N × 1000
weight of sample
PSI Standerds:
Standard POV value is 1.5 – 2.
PEROXIDE VALUE OF REFINED OIL Oil T1 T2 T3 T4 T5
COTTONSEED 0.41 0.50 0.42 0.60 0.51 CANOLA 0.53 0.42 0.50 0.41 0.64
SUNFLOWER 0.52 0.61 0.43 0.70 0.51 PALM OLEIN 0.41 0.50 0.62 0.40 0.51
8) VITAMINS TEST
For refined oil
REAGENTS:
Antimony trichloride
EQUIPMENT:
Test tube, Test tube holder
PROCEDURE:
25
Take the sample after refining in beaker.
Add Antimony trichloride in it.
If it settle down with blue color it means vitamins are present in
the oil.
If settle down with no color or other colour than blue it means
vitamins are absent.
9) REFRACTIVE INDEX
EQUIPMENT:
Refractometer
PRINCIPLE:
The refractive index of liquid fat & oil sample is measured by means of
suitable refractometer at costant temperature and using monochromatic
light source,emitting monochromatic light by means of sodium vapour
lamp.
PROCEDURE:
Circulate water in Abbe’s refractometer and note the
temperature.
Place a drop of fat or oil on the glass prism.
Close and take reading on scale.
Make correction with the help of chart provided for correction.
10) SPONIFICATION VALUE
For crude oil
PRINCIPLE:
Boiling the sample with ethanolic KOH in reflux condenser.Tritrating
the excess KOH with standard solution of HCl.
REAGENTS:
Alcoholic potash, 0.5N HCl, Phenolphthalene indicator
EQUIPMENT:
Conical flask, Burette, Water bath, Hot plate, Condenser
PROCEDURE:
26
Take 5g of sample in dried conical flask.
Add 50mL of 0.5 N alcoholic potash.
Sponify it for 1 hours under condenser.
Cool it and tritrate it against 0.5 N HCl using phenolphthalene
indiator.
Also perform blank tritration.
Calculate by using the formula:
Wt. of sample = 5 g
Sample reading = 24 mL
Blank tritration reading = 10 mL
Difference = 14 mL
Sp. Value = 56.1 × N of HCl × tritration reading
Wt. of sample
= 56.1 × 0.5 × 14
5
= 78.54
11) IODINE VALUE
For crude and refined oil
PRINCIPLE:
The product to be investigated is treated with an iodide monochloride
solution.After addition of halogen has taken place,the excess of iodine
monochloride is determined by tritration with Na-thiosulphate.
REAGENTS:
KI solution, Carbon tetrachloride, Iodine monochloride, N/10 Na-thiosulphate,
Starch indicator
PROCEDURE:
Take 0.25g sample in a flask.
Add 10mL carbon tetrachloride and 20mL iodine monochloride
solutions.
27
Cover the flask with stopper moistened with 10% KI solution.
Allow the flask to stand in dark place.
After a period of 30 min. add 15ml of 10% KI solution,washing
the stopper and sides of flask with 100mL distilled water.
Tritrate the contents with N/10 Na2S2O3 using starch indiator
Note the volume of Na2S2O3 .
Also perform blank tritration.
Caculated by given formula:
Iodine value = (b-a) 0.01269 ×100
Wt. of sample
12) GENERAL APPERANCE
EQUIPMENTS:
Beaker.
REAGENTS:
Reference Sample.
PROCEDURE:
Draw Sample from oil tanker in Beaker.
The sample should show the following properties.
It should be clear.
It should be free from any turbidity.
It should be not contain any foreign matters.
It should not show any cloudiness.
It should be clear, obvious &free from all unwanted foreign
matters.
The Sample should be true to Reference Sample.
28
13) SMELL
EQUIPMENTS:
Beaker.
REAGENTS:
Reference Sample.
PROCEDURE:
Draw a sample of Oil in beaker.
The smell should be pleasant.
It should determine the oil sample true to type.
It should not show its own natural peculiar smell to be pleasant or
appealing to analyzer.
The smell of the drawn sample must with reference sample available in
Quality Assurance Department.
Reference Oil Sample:
Palm oil (R.B.D) refined bleached Deodorized
Soya Bean Oil (S.B.O)
Cotton Seed Oil (C.S.O)
Sun flower Oil
14) MELTING POINT
EQUIPMENTS:
Water Bath Apparatus, Thermometer oC, Capillary Tube, Sprit lamp
REAGENTS:
Representative Sample (Liq. Form)
PROCEDURE:
Thoroughly mix the sample for which the melting point test is
carried out.
Heat the sample on oven until it is converted from semi-solid to
liquid state.
Thermometer 0C -100C is immersed in water previously cooled
to 10 oC – 15 oC, contained in 250 ml beaker having a manetic
stirrer.
29
Heat up the water gently with hot plate followed is gently
stirring.
Note the temperature at which the sample is completely melted.
It will be the melting point of the ghee.
Continue stirring and note the temperature at which the samples
slips in capillary tube take the average temperature of slipping.
It will be the slipping point of oil.
MELTING POINT DURING PROCESSING SAMPLE MELTING POINT OC
1 38 2 37
3 37 4 36
15) CLOUD P0INT
EQUIPMENTS:
Glass Beaker (100mL), Water Bath, Thermometer oC (-10 oC to 110 oC),
Ice.
REAGENTS:
Representative sample (Liq. Form).
PROCEDURE:
The sample must be completely dry before conducting the test.
Filter 60 to 75 gm of molten oil sample using a filter paper.
Heat the filter oil sample to 125 oC for 5 minutes immediately
before conducting the test.
Pour about 45 mL of the warm oil sample into a sample bottle.
Begin to cool the bottle and content in the water bath.
To keep the temperature uniform, stir continuously.
When the sample has reached a temperature about 10 oC above
cloud, begin stirring rapidly in a circular motion so as to prevent
supper cooling and solidification of fast crystal on the side or
bottom of the bottle.
30
Do not remove the thermometer from the sample, since to do it
may introduce air bubbles, which will interface with the test.
The test bottle is maintained in such a position that the upper
level of the sample in the bottle and the water level in the bath
are about the same.
Remove the bottle from the bath and inspect regularly.
Repeat the analysis using a water bath temperature at 5 oC below
the cloud value obtained in the first determination.
Record the cloud point obtained in oC, expressed to 1 decimal
place.
5. SOLUTION PREPARATION
a. PREPARATION OF STARCH INDICATOR SOLUTION
PRINCIPLE:
Starch solution is prepared by dissolving the starch in distilled water.
SCOPE:
This procedure is applicable for preparation of 1% starch indicator solution.
EQUIPMENTS:
Weighing Balance, Suitable means of mechanical agitation, 250 mL Beaker,
Volumetric flask capacity of 100 mL, Funnel.
REAGENTS:
Starch, Distilled water.
PROCEDURE:
Weigh 1g starch and transfer in a 250 mL beaker.
Dissolve the starch (solution) from beaker to 100 mL volumetric
flask.
Transfer the dissolved starch (solution) from beaker to 100 mL
volumetric flask.
Rinse the beaker thoroughly with distilled water and transfer in
to volumetric flask.
31
Make-up the volume with distilled water up to 100 mL
mark.Cover and manually shake the flask to mix the solution
thoroughly.
Transfer the solution to an appropriately labeled reagent bottle.
b. PREPARATION OF SATURATED POTASSIUM IODIDE
SOLUTION
PRINCIPLE:
Potassium Iodide solution is prepared by dissolving the potassium iodide crystals
in distilled water up to saturation point.
SCOPE:
This procedure is applicable for the preparation of saturated Potassium iodide
solution.
EQUIPMENTS:
Weighing Balance, Suitable means of mechanical agitation, 250 mL Beaker.
REAGENTS:
Potassium iodide crystals, Distilled water.
PROCEDURE:
Weigh 100 g of Potassium iodide crystals and transfer in a 250
mL beaker containing 100 mL of distilled water.
Dissolve the potassium iodide crystals in distilled water by using
the magnetic stirrer.
If no sedimentation is observed at bottom of the beaker, add
more
potassium iodide crystals.
Stir the solution constantly and make sure that about half inch
layer of potassium iodide crystals have been deposited at the
bottom of beaker. It indicates the saturation of solution.
Transfer the solution to an appropriately labeled reagent bottle.
c. PREPARATION OF PHENOLPTHALEIN INDICATOR
SOLUTION
FORMULA:
32
C20H14O4
PRINCIPLE:
Phenolphthalein solution is prepared by dissolving the phenolphthalein in ethanol.
SCOPE:
This procedure is applicable for the preparation of 2% phenolphthalein indicator
solution.
EQUIPMENTS:
Weighing Balance, Suitable means of mechanical agitation, 250 mL Beaker,
Spatula, Volumetric flask 1000 mL capacity, Funnel.
REAGENTS:
Phenolphthalein, Ethanol
PROCEDURE:
Weigh 20 g of Phenolphthalein and transfer in a 250 mL beaker.
Dissolve the phenolphthalein in ethanol by using the magnetic
stirrer.
Transfer the dissolved phenolphthalein (solution) from beaker to
1000 mL volumetric flask.
Rinse the beaker thoroughly with ethanol and transfer in to
volumetric flask.
Make-up the Volume with Ethanol up to 1000 mL mark. Cover
and manually shake the flask to mix the solution thoroughly.
Transfer the solution to an appropriately labeled amber reagent bottle.
d. PREPARATION OF ACETIC-CHLOROFORM SOLUTION
PRINCIPLE:
Acetic acid-chloroform solution is prepared by mixing glacial acetic acid and
chloroform.
SCOPE:
33
This procedure is applicable for the preparation of 60:40 acetic acid and
chloroform solution respectly.
EQUIPMENTS:
Graduated cylinder,1000 mL.
REAGENTS:
Glacial acetic acid, Chloroform.
PROCEDURE:
Accurately measure 400 mL of chloroform by a graduated
cylinder and transfer to amber reagent bottle.
Then accurately measure 600 mL of glacial acetic acid by a
graduated cylinder and transfer reagentbottle already containing
choloroform.
Mix the contents of bottle well.
e. PREPARATION & STANDARDIZATION OF SODIUM
HYDROXIDE
PRINCIPLE:
Sodium hydroxide solution is prepared by dissolving the sodium hydroxide in
distilled water and standardized by titrating it against 0.1N potassium hydrogen
phthalate solution to the pink color end point.
SCOPE:
This procedure is applicable for the preparation and standardization of 0.1N
solution of sodium hydroxide.
EQUIPMENTS:
Weighing balance, Dissecator, Suitable means of mechanical agitation, Spatula,
Beakers 250 mL & 1000 mL capacity, Buette 50 mL, Volumetric flask of 1000
mL capacity, Funnel, Cyinder 100 mL, Pipette 25 mL.
REAGENTS:
Sodium hydroxide (NaOH) pellets, Potassium hydrogen phthalate solution 0.1N,
Phenolphthalein Indicator solution, Distilled water.
34
PROCEDURE:
Weigh 4.3 g of sodium hydroxide pellets and transfer in a
beaker.
Dissolve the sodium hydroxide pellets with distilled water by
using the magnetic stirrer.
Transfer the dissolved pellets (solution) from beaker to 1000 mL
volumetric flask.
Rinse the beaker thoroughly with distilled water and transfer into
volumetric flask.
Make the volume with distilled water up to 1000 mL mark.Cover
and manually shake the flask to mix the solution thoroughly.
Transfer the solution to an appropriately labeled reagent bottle.
Filter and standardized the clean solution.
STANDARDIZATION:
Take 25 mL of 0.1N potassium hydrogen phthalate solution with
the 25mL pipette in a 250 mL beaker.
Add 100 mL distilled water and Stir it manually or with
magnetic stirrer.
Add approximately 1.0 mL of phenolphthalein indicator.
Titrate with sodium hydroxide solution with constant stirring to
light pink end point.
Record the “mL” used of sodium hydroxide solution.
CALCULATION:
Normality (N) = Normality of KHP x mL used of KHP
mL used of NaOH
f. PREPARATION & STANDARDIZATION OF SODIUM
THIOSULPHATE
PRINCIPL:
Sodium thiosulphate solution is prepared by dissolving Sodium Thiosulphate &
Sodium carbonate in distilled water and standardized by titrating it against 0.1N
potassium dicheomate solution to the colorless end point.
35
SCOPE:
This procedure is applicable to prepare and standardize 0.1N Sodium
Thiosulphate solution.
EQUIPMENTS:
Balance, Dissector, Suitable means of mechanical agitation, Spatula, Beakers
250mL & 1000 mL capacity, Burette, Flask volumetric of 1000 mL capacity,
Funnel, Culiner, 100 mL, Pippette, 25mL.
REAGENTS:
Sodium thiosulphate, Sodium carbonate, Potassium dichromate, Hydrochloric
Acid, Concentrated, Potassium Iodide solution, Saturated, Starch indicator
solution, Distilled water.
PROCEDURE:
Weigh 25.5 g of Na2 S2 O3. 5H2O in a beaker.
Dissolve it with distilled water by using the magnetic strirer.
Transfer the dissolved pellets (solution) from beaker to 1000 mL
volumetric flask.
Rinse the beaker thoroughly with distilled water and transfer in to
volumetric flask.
Make-up the volume with distilled water up to 1000 mL mark.
Cover and manually shake the flask to mix the solution thoroughly.
Transfer the solution to an appropriately labeled amber reagent bottle.
STANDARDIZATION:
Take 25mL of Potassium dichromate solution (0.1N) with the 25mL
pipette in a 250 mL beaker.
Add 5 mL of concentrated Hydrochloric acid solution and stir it manually
or with magnetic stirrer.
Add 2 mL of saturated Potassium iodide solution.
Titrate it against 0.1N Sodium thiosulphate solution till pale yellow color.
Add approximately 1.0 mL of starch indicator solution as an indicator and
continue titration till colorless end point.
36
Record the “mL” used of Sodium thiosulphate solution.
CALCULATION
Normality (N) = mL taken of Potassium dichromate
1000xmL used of Sodium thiosulphate x0.04
g. PREPARATION OF POTASSIUM HYDROGEN PHTHALATE
Formula of potassium hydrogen phthlate is C8H5KO4.
PRINCIPLE:
Potassium hydrogen phthalate solution is prepared by dissolving the dried
potassium hydrogen phthalate in distilled hot water (60 0C) and cooling it to room
temperature.
SCOPE:
This procedure is applicable for the preparation of potassium hydrogen phthalate
solution.
EQUIPMENTS:
Oven, Balance, Dessicator, Suitable means of mechanical agitation, Beakers 250
mL & 1000 mL capacity, Volumetic flask 1000 mL capacity, Funnel, Spatula,
Cylinder 100 mL.
REAGENTS:
Potassium hydrogen phthalate (KHP), Distilled water .
PROCEDURE:
Dry the potassium hydrogen phthalate (KHP) at 120 0C in oven
for 2 hours.
Cool it in the dessicator for 30 minutes.
Accurately weigh 20.422 g of Potassium hydrogen phthalate and
transfer to 1000 ml volumetric flask.
Add 600 mL hot (60 oC) distilled water in the flask containing
KHP and shake it well.
When it dissolved properly, allow to cool at room temperature.
Make-up the volume with distilled water up to 1000 mL mark.
37
Cover and manually shake the flask to mix the solution
thoroughly.
Transfer the solution to an appropriately labeled amber reagent
bottle.
6. CONCLUSION
At last it’s concluded that every step of ghee and oil processing from receiving of
crude oil till packaging of final product is carried out under hygienic conditions.
All the rules and regulations not only related to food safety but also related to
safety of the employees are followed strictly. From these results it is proved that
quality of Vanaspati ghee and cooking oil available in Pakistan according to the
standards set by PSQCA. The values of free fatty acids, nickle content and
peroxide are significantly low as compared to standard values. Healthy and
nutritious Vanaspati ghee and cooking oil is available for consumer.
Internship duration of 10 weeks make a lot of contribution in my practical
knowledge related to processing of vegetable o
38
7. REFRENCE:
1. ANDERSEK, A. J. c. (1953). "Refining of Oils and Fats."
2. AOAC (2000). "The Official Methods of Analysis " (17).
3. Association, C. R. (2006). "Corn Oil." (5).
4. Authority, P. S. a. Q. C. (2003). "Pakistan Standards."
5. BAILEY, A. E. (1951). "Industrial Oil and Fat Products."
6. Che Man Y.B., T. C. P. (1999). "Effects of natural and synthetic
antioxidants on changes in refined, bleached, and deodorized palm
olein during deep-fat frying of potato chips." 76: 331-339.
7. E., L. (1977 ). "Laboratory Methods for Sensory Evaluation." 1637.
8. ELLIS, C. (1914). "The Hydrogenation of Oils."
9. Firestone, D. e. (1989). "Official and Recommended Methods of the
American Oil Chemists’ Society, Methods."
10. Hamilton R.J., D. and H. R. J. A.J., Hamm W. (ed.) (2008). "Fatty
acids: structure, occurrence, nomenclature, biosynthesis and
properties." 1-24.
11. Harrod, M., and P. Moller, (1996). "Hydrogenation of a Substrate and
Products Manufactured According to the Process."
12. J.B., R. (1986). "Classical analysis of Fats and Oils. In: Hamilton R.,
Rossel J. (ed.): Analysis of Fats and Oils." 1-90.
13. Koritala, S., J.P. Friedrich, and T.L. Mounts (1980). "Selective
Hydrogenation of Soybean Oil. X. Ultra High-Pressure and Low-
Pressure." 57: 1–5
14. Patterson, H. B. W. (1994). "Hydrogenation of Fats and Oils ": 39–40.
15. PSQCA (2003). "Specification for cooking oil (Blended)."
16. Smouse, T. H. (1994). "Factors affecting oil quality and stability in
methods to assess oil quality and stability of oils and fat containing
food." 17-36.
17. Susu, A. A., and A.F. Ogunye (1981). "Nickel-Catalyzed
Hydogenation of Soybean Oil." 58: 657–661.
39
18. Tacke, T., S. Wieland, P. Panster, M. Blankmann, R. Brand, and and
H. Magerlein (1998). Hardening of Unsaturated Fatty Acids, Fatty
Acids, or Fatty Acid Esters,.
19. Duff, J. H. (2002). ""Heavy metals" a meaningless term? (IUPAC
Technical Report)" Pure and Applied Chemistry." 74: 793–807.
20. Gunstone, F. D. (2011). Vegetable Oils in Food Technology
Composition, Properties and Uses, Times by SPi Publisher Services,
Pondicherry, India.
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