INTRODUCTION TO PRODUCTION,

PROCESSING AND QUALITY OF PALM

AND PALM KERNEL PRODUCTS

Chong Chiew Let

Head

Analytical & Quality Development Unit

Product development and Advisory Services Division

Malaysian Palm Oil Board (MPOB)

Kementerian Produk Peladang dan Komoditi (KPPK)

Palm Oil Familiarization Programme

2009 Kuala Lumpur

INTRODUCTION

Oil palm is a tree crop which bears fruit three years after planting

INTRODUCTION (con’t)

Palm oil: from mesocarp of the palm fruit

Palm kernel oil: from kernel inside the fruit

Palm kernel oil is meant for propagation of the specie

Five

major sectors of

Malaysian PO

industry

Plantation sector Milling sector

Refining sector

Oleochemical sectorKernel crushing

sector

Effect of Plantation Practices on the

Quality of CPO

Bunch ripeness

Bruising of fruits during

harvesting

Transportation of ffb to

mill as soon as possible

B) Sterilization

Objectives of bunch sterilization are:-

• Deactivation of enzymes to prevent further rise in FFB

• Facilitate stripping of fruits

• Preparation of fruit mesocarp by coagulating mucilaginous material which facilitates oil cell rupturing

• Reconditioning of nuts to minimise kernel breakages during pressing and nut cracking

Sterilization (cont)

•Horizontal sterilizers are generally used

•FFB is subjected to steam-heat

treatment

•Saturated steam at a pressure of 3

kg/cm2 is used for heating

•3 peak sterilization cycle used

•Sterilizing cycle time: 75 to 90 minutes

C) Stripping

“cooked” FFB are fed into a rotary drum thresher for

separation of fruits from bunch stalk

As drum stripper rotates, bunches are lifted up and then

dropped repeatedly as the bunches travel along the stripper

The fruits are knocked off the bunch by impact action

Detached fruits pass through the bar screen and are collected

underneath by conveyors and discharged into digester

Empty bunches (EFB) are discharged at the end of the

stripper continuously

D) Digestion

Sterilized fruit mesocarp must be

loosened from the nuts in preparation

for mesocarp pressing

Digestion involves mashing of palm

fruits heated conditions

Heating : by steam jacket around

digester or live steam injection

The digester is a vertical cylindrical

vessel fitted with a rotating shaft fitted

with a number of stirring arms

Fruits are mashed and heating will

rupture oil bearing cells

E) Pressing

CPO is extracted by means of a twin screw press

Hot water added to assist oil flow when necessary

CPO slurry is collected in crude oil tank for purification

Press cake is conveyed to a depericarper for separation

The press is operated to press out oil without breaking any nuts

Possible to reduce nut breakages by employing double pressing

which is practiced by a number of palm oil mills in the country

F) Clarification and Purification of CPO

Oil is sent to a vibrating screen of 30-40 mesh to remove fibres and residues

It is then pumped to a continuous horizontal or vertical clarification tank for

oil separation

Temperature of clarification: 90°C to enhance oil separation by density

differences

Clarified oil is centrifuged to remove impurities

Cleaned oil is then vacuum dried and cooled to 45°C before storage

CPO: moisture and dirt content of below 0.2% and 0.025% respectively.

G) Depericarping

Press cake consists of a moist and oily fibres and nuts

mixture

Mixture is conveyed to a depericarper for nut and fibre

separation

Fibre, separated from by winnowing, is sent to boiler

house for boiler fuel

Nuts are sent to a rotating drum where remaining fibre is

removed by attrition before being sent to a nut cracker

H) Kernel Extraction

Nuts are dried and cooled to loosen kernel from shell

before cracking : “conditioning”

Nuts are cracked in a nut cracker by impact

The shell and kernel are separated by winnowing

followed by a clay bath or hydrocyclone

Kernel is then dried in a kernel silo dryer to reduce

moisture to below 7% to prevent mould growth

Palm oil milling process

Steriliser

Loading ramp

Stripping

Digester

Press

Nut/fiber

separationOil/water

separation

Fresh fruit bunches (ffb)

Empty fruit bunches

crude oil storage heating fiber for fertilising

nuts to storage

bruising

Iron

Milling Practices

that can affect

the quality of

CPO:

Quality of Crude Palm Oil

The sale specifications of

crude palm oil within

Malaysia are (MPOA):-

FFA 5.0% max

M & L 0.25% max

DOBI 2.3 min

Quality of Palm Kernel

MEOMA

Dirt & Shell (%) 6% max 10%

rejectable

Moisture (%) 7% max 10%

rejectable

FFA (%) 5% max

(as lauric acid)

PALM KERNEL CRUSHING SECTOR

Extraction Process

Three types of extraction processes are

used:

Mechanical Extraction using high

pressure screw press

Direct solvent exraction

Prepressing followed by solvent

extraction

Mainly mechanical extraction used

Palm Kernel Oil Extraction: Pretreatment

Feed kernels are cleaned using magnetic traps to remove

metal debris

Vibrating screens for sieving out sand, stones/other

undesirable materials

Kernels are than broken into small fragments to facilitate

flaking by roller mill

Roller mill roll kernel into flakes of 0.25 – 0.4mm thick

Kernel flakes are then steam conditioning in stack

steamer to, rupture cell wall

Screw Pressing

Cooked kernel meal is fed into a screw-press

Expelled oil is drained through perforations cage

Oil Clarification

Expelled palm kernel oil is decanted or screened to

remove fines and foot

A filter press is also used in order to produce a clean

oil prior to storage

The cake discharged from the press is conveyed for

storage in a silo

Quality of Crude Palm

Kernel Oil

FFA 5.0% max

M&I 0.5% max

IV 19 max

PALM OIL REFINING

Removal of

odoriferous materials

Reduction of ffa

Reduction of oil colour

Preservation of minor

components

Objectives of refining

palm oil products

REFINING OF PALM OIL

Two type of processes

• chemical (alkali)

• physical refining

Chemical Refining

Chemical Refining consists of degumming,

neutralising, bleaching and deodorising

High operating costs and high refining losses,

problems of pollution due to soapstocks

ALKALI REFINING

DEGUMMING

NEUTRALISATION

PRETREATMENT

BLEACHING

DEODORIZATION

DEGUMMING

DEACIDIFICATION/

DEODORIZATION

PHYSICAL

REFINING

NBD RBD

PRETREATMENT

BLEACHING

Malaysia:Mainly physical refining

Physical Refining

Physical refining process involves only

degumming, bleaching and deodorisation

In the deodoriser, stripping steam is used

to deacidify the oil under vacuum

Refining losses and costs are much lower

Physical refining is most widely used in

Malaysian palm oil refining industry

PRETREATMENT: DEGUMMING and BLEACHING

DEGUMMING

Phosphoric acid is added to degum the oil

Conditions phospholipids and trace metals prior

to earth bleaching

BLEACHING

Bleaching : non-activated clay, activated carbon

and silica are generally used

Acid activated bleaching earth is sometimes used

Pretreatment bleaching……

The most important property is the

catalytic decomposition of the

hydroperoxides in the oil

The primary function of the bleaching

earths during pretreatment is the

removal of peroxides and secondary

oxidation products

The secondary function is to clean up

traces of soap, phosphatides, trace

metals and pigments in the oil

PRETREATMENT BLEACHING

DEGUMMING

VACUUM BLEACHING

FILTRATION

SECURITY FILTRATION

PHOSPHORIC ACID

BLEACHING EARTH

CRUDE PALM OIL

DEG BL PO

Vertical Leaf Filter

DEODORISATION

The last step in the refining process is deodorisation

Oil is heated to 260°C under vacuum to remove undesired

odours in chemical refining

For physical refining, main aim is removal of FFA with

injected steam

Deodorization removes:

free fatty acids carotenoids break down

ketones & aldehydes other volatiles

pesticides & other HC volatile oxidation products

PORAM Standard Specifications

For NBD/RBD Palm Oil

FFA (as palmitic) 0.1% max

M&I 0.1% max

IV (Wijs) 50-55

MP/oC 33-39

(AOCS Cc3-25)

Colour (51/4”cell) 3 or 6 Red max

NBD/RBD Palm Kernel Oil

Specifications For Export

FFA (as lauric) 0.1% max

M&I 0.1% max

IV (wijs) 19 max (shipment time)

Colour (51/4”cell) Red 1.5 max

FRACTIONATION

Three fractionation methods used:

Crystallisation of PO; separation by filtration (Dry

Fractionation)

Crystallisation of PO in solvent; filtration (Solvent

Fractionation)

Partial Crystallisation of PO and mixing with surface

active agent (sodium lauryl sulphate) ; centrifuging

(Detergent Fractionation)

Liquid fraction: olein Solid fraction: stearin

Liquid fraction: refractionated to yield superolein and

PMF

Fractionation principle

Slurry

Molten

fat

Olein Stearin

solid/liquid separation

crystallisation

8

Membrane filter press Courtesy of

Some Value-added Down Stream Products of A

Refinery

• Palm Mid-Fraction for Cocoa Butter Equivalent

(CBE)

• Cocoa Butter Substitute (from Palm Kernel Oil)

• Cocoa Butter Extender (from hydrogenated

superolein)

• Fully hydrogenated products

• Interesterified products

PORAM Specifications of Palm

Olein and Stearin

RBD/NBD RBD/NBD

Palm Olein Palm Stearin

FFA (as palmitic) 0.1% max 0.1% max

M&I 0.1% max 0.1% max

IV 56 min 48 max

MP 24 max 44 min

Colour 3 or 6 Red 3 Red

Thank you