M7180-DS intro 9-8 JLG to Mediasense-v12sk Classified - Internal Use Only TEKNOLOGI MINYAK DAN...

M7180-DS intro 9-8 JLG to Mediasense-v12sk

Classified - Internal Use Only

TEKNOLOGI MINYAK DAN LEMAK

Internal use onlyM7180-DS intro 9-8 JLG to Mediasense-v10sk

The Importance of Fats/Oils

a. High content of energy (the greatest possible storage of energy in the smallest possible amount of food substance)

b. Allow human to consume fat soluble-vitamins and provide essential fatty acids

c. Provide a smooth, creamy consistency to many dishes (good mouth-feel)

d. Economic aspect (> 90 mill ton of oils and fats)….national interest- 60 mill ton of palm fruit- 11 mill ton of olives- > 200 mill of oil seeds


e. Substantial market for technical fats

Oil type and non food usage (%)- Soybean oil 0.25- Palm oil 10- Palm kernel oil 10- Rapeseed oil 40- Coconut oil 55- Castor oil 100- Linseed oil 100- Tung oil 100


Type of usage (% of total non food usage)- Fatty acids 36- Animal feed 29- Soap 15- Other 13- Paints 3- Lubricants 2- Polymers 2


Comparison of Diesel oil, rapeseed oil and sunflower oil

Sunflower RapeseedDiesel oil Crude oil Methyl ester Crude oil Methyl

ester

1. Caloric value (MJ/kg) 42-46 39.28 40.16 37 37.02-37.20

2. Density (g/cm3) 0.835 0.925 0.880 0.92 0.86-0.90

3. Viscosity (cP, 20oC) 3.9 34.7 4.22 68-97 6-9

4. Flash point (oC) 50-77 215.5 183 317-324 111-175


Energy balance from renewable sourcesSource Energy balance invested/yielded Energy yield net (GJ/ha)

Sunflower oil 2.8 43.3

Rapeseed oil 2.7 37.9

Ethanol (sugar beet) 2.5 58.9

Corn 1.3 18.4

Wheat 1.1 5.2

Requirements for fuel esters

FFA < 0.2%

Mono, diglycerides < 0.1%

Glycerol < 0.1%

Methanol < 0.2%

Water < 0.1%

Metals (each) < 5 ppm


Components of fats and oils

Fats/Oils : esters of fatty acids with the trihydric alcohol glycerol

1. Glycerol- propane-1,2,3-triol)- Physical data (molecular weight 92.11, melting point 20oC,

density 1.2611 g/cm3, viscosity 1 759.6 cP, solubility in water/alcohol infinitely)


Fatty Acido > 200 are knowno Monocarbonic acid, usually derived from aliphatic hydrocarbono The structure of fatty acid has a great influence on their physical

data


Occurrence of Fatty Acids

Saturated fatty acids (CnH2nO2)n Trivial name Occurrence in common oils and fats

4 Butyric Milk fats (3 – 5)

6 Caproic milk fat (2-3), coconut oil (<1)

8 Caprylic milk fat (< 2, )


Fats and oils of plant origin

Linseed oil : seed of the flax plant Linum usitatissimum, major constituent linolenic acid, mainly used in the paint and varnish industry

Tung Oil (China wood oil) : seed or nut of the tree Aleurites fordii and Aleurites montana, highly unsaturated oil (eleostearic acid), rapid drying properties

Sunflower seed oil : major constituent linoleic and oleic acids

Corn oil : oleic and linoleic acids

Tomato seed oil : by product of tomato paste manufacture, oleic and linoleic acids


Sesame oil : oleic and linoleic acids, high content of saponifiable matter such as sesamine and seasamoline (give distinctive color reaction)

Cotton seed oil : high content of linoleic acid

Safflower oil : seed of Carthamus tinctorius, linoleic acid, drying oil (intermediate characteristic between soybean and linseed oil)

Soybean oil : high content of linoleic acid, the crude oil contains large amount of non glyceride material (phosphatide)

Rice bran oil : bran of Oryza sativa, contain large amount of non glyceride material and active lipase, the acidity (during storage) rises at the rate of 1% per hour

Kapok oil : seed of Ceiba pentandra, palmitic, oleic and linoleic acids


Castor oil : seed of Ricinus communis, high acetyl or hydroxyl value, high specific gravity, high viscosity, high solubility in glacial acetic acid, lower solubility in petroleum solvent……high content of ricinoleic acid

Palm oil : palmitic, oleic and linoleic acids

Palm kernel oil : lauric and myristic acids

Cocoa butter/cacao butter : bean of Theobroma cacao, has a specific odor and flavor, palmitic, stearic and oleic acids

Coconut oil : has a specific odor, lauric and myristic acids


Fats of animal origin

Hog (pig) fat or lard : bacon (subcutaneous fatty tissue), lard/hog fat (rendered from the internal tissues), palmitic, stearic and oleic acids

Tallow : from the fatty tissues of cattle, sheep and goats, palmitic, stearic and oleic acids

Sardine oil : from the body of the Caerulea and Ocelata sardinops, palmitic acid

Cod liver oil : from the fish Gadus morrhua, high content of vit A and D


Physical Properties

Specific gravity/Density

- the specific gravity increases along with increase in the degree of unsaturation

- the hydrogenation of fat lower heir specific gravity

Melting Point

- the melting point of a fatty acid increases together with the increase in the chain length of the acids

- the higher unsaturation degree of a substance the lower its melting point

- the melting point of a triglyceride is related to that of the corresponding fatty acids

- the melting point of a diglyceride is higher than that of the corresponding triglyceride


Butyric acid -8

Caproic acid -1

Caprylic acid 16

Capric acid 31.3

Lauric acid 43.4

Myristic acid 54.4

Palmitic acid 62.9

Stearic acid 69.6

Oleic acid 16

Elaidic acid 44

Erucic acid 34

Linoleic acid -7

Linolenic acid -13


Boiling Point

-the boiling point of fatty acids increases together with increase in their chain length

- the vapour pressure of a glyceride is always considerably lower than that of the corresponding fatty acid

Iodine Value : a measure for determining the unsaturation degree of fats and fatty acids, defined as the amount of iodine (in gram) which is absorbed by 100 gram of fat

Peroxide Value : a measure for determining the content of reactive oxygen of fats and oils in terms of milliequivalents of oxygen per 1000 gram fats, for evaluating their keeping qualities or shelf life.


Acid Value : a measure used for determining the content of free fatty acids

contained in oils/fats; defined as the number of milligrams of potassium

hydroxide needed to neutralize the FFA contained in 1 gram of fat; the acidity

of fats and oils is expressed in terms of %FFA; acid value : FFA = 1 : 0.503

Saponification Value : the number of milligrams of potassium hydroxide

needed to saponify 1 gram of fat.

Acetyl Value : refers to the determination of the free hydroxyl groups

contained in fats and oils; represented by the number of milligrams of

potassium hydroxide needed to neutralize the acetic acid produced by

splitting of 1 gram of acetylated fat

Hydroxyl Value : the number of milligrams of potassium hydroxide required to

neutralize the number of hydroxyls contained in 1 gram of fatty acids.


MINOR COMPONENTS OF FATS AND OILS

Phosphatides

• glycerophosphatides

• sphyngolipids

Unsaponifiables (the portion of oils and fats which is not saponified; varies 0.5 – 2%)

• sterols (simply alicyclic alcohols)

• vitamins-tocopherols (vit A, D, E, K)

• waxes (the fatty acids present instead of being esterified with glycerol are esterified with a sterol or a aliphatic alcohol C26 – C36)

• coloring substances

• aliphatic and terpenic alcohols

• saturated and unsaturated hydrocarbons


PURIFICATION OF FATS AND OILS

SUBSTANCES MUST BE REMOVED :1. Solid impurities (solids or meal fines)The most serious troubles :- Formation of difficult to process sludge in storage tanks- Neutral oil losses during neutralization (fines act as emulsifier)- Slowing down of the processing cycle2. Mucilagenous materials, phosphatides, peroxides etc- Soy bean 1.5 – 3%- Rapeseed 1.5 – 2.5%- Maize 1 - 2% - Cottonseed 0.5 – 1.5%- Sunflower 0.5 – 1%


3. Volatile impurities (water, solvent, ether etc)

4. Trace metals such as copper and iron (pro-oxidants)

5. Pigments, primary and secondary oxidation products

6. Waxes and unsaponifiables


Degumming with phosphoric acid• Acid charred & precipitated (coagulated) proteins, phosphatides,

gum• Separation : settling & centrifugation• Crude oil is heated to 70 – 80oC, mixed with acid solution (0.3 –

0.4%, 15 – 20 minutes)• Sulphuric acid : 66o Be, temp 30oC, high temp : partial sulphonation

of oil (red color)• Acid : phosphoric, oxalic, citric, sulphuric

Water degumming (purification by hydration)• Phosphatides, proteins & other colloidal impurities soluble in the oil

only in anhydrous form…… precipitated in the form of flocs of higher specific gravity


NEUTRALISATION OF FATS AND OILS

Acidity of the oil : expressed as oleic acid (in general as this acid is present in all fats and oils)

Source of acidity : fermentative process (special enzymes under condition of temperature split glycerides into glycerol and fatty acid.

The glycerol decomposes, the free fatty acids remain dissolved in the oil and cause its acidity to rise.

The most effective method to prevent : remove the maximum possible amount of water from the crude oil

Acidity : neutral losses (split glyceride, neutral oil loss during neutralisation)


Factors :

• purity of fats and oils

• temperatures

• strength of alkaline solutions

• saponification time

The most serious dangers : unusual losses of neutral oil, formation of emulsions hindering soapstock separation, poor settling of soap flocs


In continuous operation

Q = (Q1 x P x A x 1 000) / (100 x M x N)

Q = quantity of NaOH solution (l/h)

Q1 = quantity of oil (l/h)

P = specific weight of oil

A = acidity of the oil, expressed in percent

M = molecular weight of fatty acid

N = strength of NaOH, expressed as normality

Excess NaOH : 6% x Q


Average weight of fatty acid

Coconut oil 205

Palm kernel oil 214

Palm oil 263

Rapeseed oil 308

Wesson loss (W%) = A + I

A = % fatty acid

I = % impurities


The limits of neutralisation losses

• FFA <= 4 % = 0.8 + (1.2 x W%)

• FFA > 4% = 1.4 x W%

Strength of NaOH

• FFA < 1% : 8 – 12oBe

• FFA 1 – 6% : 20oBe

• FFA > 6% : > 20oBe

Washing of oils after neutralisation : to remove the traces of soap, by the spraying water at a temperature of 90 – 95oC


Neutralisation by Saponification

• the reverse of fat hydrolysis/fat splitting

• conducted under vacuum, in the presence of an excess of glycerol and at temperature of 250oC, catalyst zinc or zinc chloride

• the weakness : occurrence of polymerisation, color change (to red) of the esterified product, deterioration of flavor

Neutralisation by Distillation (Physical Refining)

• through distillation by injected steam to remove free fatty acid

• this process can’t be applied to all oils :

• the oils are heated up to 220 – 250oC, oils undergo certain modification to their molecular structure and consequently their chemical and physical characteristic are modified


Neutralisation Via chemical Means

Saponifying the free fatty acids present with aqueous solutions of sodium hydroxide and seldom with others (potassium hydroxide, sodium carbonate) and in separating via physical means (settling and centrifugation)

Reaction (reversible ~ temperature and pressure) Reactants : free fatty acid (R-COOH), NaOHProducts : soap (R-COONa), H2O

The reaction is conducted at atmospheric pressure and medium temperature (60 – 80oC)

Hydrolysis : high pressure (30 atm), high temperature


BLEACHING• remove coloring matters (to be adsorbed by bleaching agent)• bleaching agents : bleaching earth, activated carbon

Bleaching Earths• special clays activated by chemical or physical processes• treatments : washing by sulphuric acid solution, filtration, drying, grinding• adsorptive effect : surface tension, enhanced by the large surface area. • the treatment of the clay is to remove the foreign matters contains in its

capillary tubes so as to render it extremely porous and extend its surface.• the mineral acid treatment increases the FFA content


ACTIVATED CARBON• animal or plant origin• plant origin : dry distillation of special tree branches• the bleaching action : the large adsorbent surface of carbon held in small

volume, would influence the surface tension of the compound with which it

comes into contact, thus causing adsorption• 1 g carbon develop a surface area of several square meters• common practice : mixture of activated carbon and bleaching earth in a ratio

5 – 10 % of carbon to 90 – 95 % of clay


Before being subjected to bleaching, fats/oils must be free of moisture. The slightest traces of water in a fat may reduce the bleaching action of earths and activated carbon

Operation : heating the oil to a temperature range of 70 – 80oC under vacuum

Temperature• has a marked influence on the bleaching process• every type of oil has its own optimum temperature (need preliminary tests to determine this optimum temperature)• soy bean oil : 100oC


Time

• contact time has its influence on the decolorizing power of the adsorbent• unique for every type of oil• case : soybean oil o optimum contact time : 30 minuteso bleaching temperature : 95oCo amount of bleaching earth : 2%o absolute pressure : 60 mm Hgo agitation : vigorous

Continuous process is more effective


Absolute pressure

The surface area is made up by a countless number of capillary tubes, which in atmospheric ambient will become saturated with air (The material must be deaerated)

The simplest method : lowering the absolute pressure in the bleaching vessel to 50 – 70 mm Hg


Industrial Operation

• the bleacher is fed with a set amount of oil, temp 70 – 80oC under vacuum

pressure (barometric condenser and vacuum pump)• the agitator is operated until the moisture is completely removed• after drying, a metered amount of bleaching agent is added and the

temperature is raised to 100 – 110oC (contact time : 30 min)• The suspension is pumped to the filtration section where the two

components are separated


DEODORISATION• to remove the compound which impart an unpleasant odor and flavor • the compound (0.001 – 0.010%) : unsaturated carbohydrates, low

molecular weight fatty acids (mainly butyric acid and caproic acid,

aldehydes and ketones (formed during the various refining process)• Great difference in volatility between odoriferous substances and

glyceride• Deodorisation : based on the higher volatile properties of odoriferous

compounds (removed by distillation)• Factors : temperature, pressure, time, material of deodoriser


The boiling point :

Absolute pressure Palmitic acid Stearic acid Oleic acid

(mm Hg) (oC) (oC) (oC)

100 270 290 285

40 244 263 255

10 210 228 220

4 192 209 205

2 179 193 190


Optimum condition for operation :

• highest possible temperature

• lowest possible absolute pressure

• controlled amount of stripping steam

An excessive increase in temperature may result in distillation of part of the glycerides, polymerisation and partial hydrolysis of the glycerides

A prolonged deodorisation time has the following adverse results : polymerisation, cooked flavor of the oil, color deterioration of the refined oil

Deodorisation time : batch 5 – 12 hours, continue 1 – 3 hours


Type of oil Pressure (Torr) Temperature (oC)

Soybean 10-20 200

4-6 240

Rapeseed 10-20 200

4-6 240

Coconut 10-20 180

4-6 180

Palm 10-20 180

4-6 230

Palm kernel 10-20 180

4-6 230

M7180-DS intro 9-8 JLG to Mediasense-v12sk Classified - Internal Use Only TEKNOLOGI MINYAK DAN...

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