8/2/2019 Poster-Refining of Edible Oil
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Refining of Edible OilAman Paul, Dorcus Masih, Priyanka Malik,
Sajan Palanchoke, Sachin Verma, Anil Saini and Justin Masih
Abstract
Crude oils as received from the extraction plant need to be
refined before consumption. Removal of undesired products from
crude oils such as free fatty acids, phospholipids, oxidised
products, metal ions, colour pigments and other impurities is
really important.
Refining also aid in preservation of valuable vitamns, to
minimize oil losses and protection of the oil against degradation.
Refining consists of physical and chemical processes which are
carried out to remove undesirable natural as well as
environmental-related
components from the crude oil. A typical refining process
consist of Degumming, Neutralization, Bleaching, Deodorization and
Winterization. Degumming is process of removal of phospolipids from
the oil. It may be done by processes involving water, acids or
enzymes. Neutralization is carried out for removal of free fatty
acids. It is done either by chemical or physical processes.
Bleaching process is used to oxidize the coloring matter which
makes it undesirable. Bleaching earth or activated carbon are used
for
discolorization. Deoderization is done through pressurized steam
distillation, which removes undesirable odors and tastes from the
oil. Winterization is the removal of the more saturated glycerides
from edible oils so that it remains bright and clear at low
temperatures.
Need for Refining
Removal ofundesirablematerials
FreeFattyAcids
Phospho-lipids
OxidizedProducts
MetalIons
ColorPigments
OtherImpurity
(s)
Preservationof valuablevitamins
(VitaminE- Tocopherols)
Minimizeoil losses
Protectionof oil against degradation
OtherFunctions
Degumming
Neutralization
Bleaching
Deoderization
Winterization
Flow Chart of Refining
Degumming Need of Degumming
The emulsifying action of phospholipids increases oil losses
during alkali refining.
Gums lead brown discoloration of oil after heating during
deodorization.
Salts may be formed with cooper, magnesium,calcium and iron,
accelerating oxidative
degredation of oil.
Certain phospholipids, such as lecithin, find widespread
industrial application.
Types of Gums1. Hydratable phosphatides or HP
(easy to remove)
2. Non hydratable phosphatides or
NHP (hard to remove)
Note- NHPneed to be hydrolyzed to
hydratable through acids.
Mechanism of Hydrolysis
Oil
NHP
Water
P
C P
A
Oil
HP
Water
P
C P
APC-Phosphatidic
Choline
PA-
Phosphatidic
Acid
WaterDegumming
AcidDegumming
EnzymeDegumming
Heatoilto60 -70 C
Water additionand mixing
Hydrationmixing(30 minutes)
Centrifugal separationof hydratedgums
Vacuum dryingof degummedoil
Gums -driedfor edible lecithinorrecombinedin meal
W
aterDegumming
In this process largepart of hydratableand even a
smallproportion of thenon-hydratablephophatides are
removed.
Gums conditoned and absorbed on bleachingearth and are
separatedbyf traton
Vacuumdryng of degummed oi
Centrfugalseparaton of hydrated gums
Hydraton mixing (30 mnutes)
Acid additon and mxing
Heatoi to 60 70 C
Acid
Degumming
Dryaciddegumming
issuitablefor
processingoilswith
lowgumcontentssuch
aspalmo
il,coconut
oil,palmkerneloil,
etc.
Neazao
ObjectiveRemoval of Free Fatty Acids Removal by a
chemical reactionwith alkali(caustic
soda)
Chemical
Refining
Removal bydistillation at
higher temperatureand low vacuum
Physical
Refining
Types
Mostly Chemical
refining is used as it is
cheap.
Heatingto60to70 OC
Add conc.Phosphoric acidto condition NHP
Givetimetoreact
Addition ofdil. Causticsoda
Hot water washing
Chemical Refining
Ble
n
Oil
Colouring matter
makes oil undesirable
Bleaching is
done to oxidize
these taints
Activated Charcoal +
Bleaching Earth
Oil Tank
Programmable
Controller
Winterization or Dewaxing
In winters
sometimes oils
solidify
Waxing
of Oil
Winterization
EnsuresStability
ofOilsatLow
Temperature
Oil
Cooling to 5-10oC
Ppt Oil
Filtration
Process Flow
Deodorization
Oil
Oil has
undesirable
flavorand
taste
Deodorization
removes these
offodorsand
tastes
PressureSteam
Distillation
240-
270oC
30-60
minDeodorizationreduces
thecontentofmany
othersubstanceslike:
Toxins
Residues
BleachingByproducts
Sulphur
Sterols
Tocopherols
BetaCarotene
Monoglycerides
1 M.Tech (Food Tech) Scholars,
SHIATS, SHIATS2 Executive, Field Fresh Foods,
Gurgaon
O Assist Prof, (Dept. of Food
Process Eng.), SHIATS
3
M.Sc (Dairy Science) Scholar,SHIATS
* Assist Prof (Dept. ofChemistry), ECC
Credentials
adjustment of theoptimalconditionsfor theenzymereaction,i.e.
optimal pH with acitratebuffer
and theoptimal temperature
addition of theenzymesolution
enzymereaction
separation of lysophosphatidefromtheoil at about 75 C
Leci
tase Ultra(Microbial
lipase)
Lecitase Novo(microbiallipase)
PancreaticphospholipaseA2
