Processing technologies for virgin coconut oil and coconut based Confectionaries and beverages

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Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
“Processing technologies for virgin coconut oil and coconut based
Confectionaries and beverages”
C Jayasekara and K D P P Gunathilake
Coconut Research Institute
Lunuwila
Sri Lanka
Abstract
Coconut palm is a multipurpose tree providing food, nutrition, shelter for millions of
people living in the tropical region of the world. Coconut kernel is use for processing of
traditional products like copra, coconut oil and desiccated coconut. Virgin coconut oil is
a newly introduced product gradually gaining popularity among people in the Western.
It is nutritious oil and has wide group of applications as a pharmaceutical, nutraceutical
and cosmoceutical. The defatted residue obtained after extraction of virgin coconut oil
can be process into high value products rich in protein and fiber. Different methods of
processing of virgin coconut oil, high value products from de-fatted coconut residue,
and beverages from tender and mature nut water are dealt in this paper.
Coconut is one of the most important tree crops in the tropical region of the world securing
food and shelter for millions of people. Coconut is grown in more than 93 countries around
the world in an area of 11.95 million ha. In addition, producing 57,510 million coconuts
annually. It is of economic importance, cultural significance and many useful uses to
humankind providing food, drink, fiber, wood, medicine, energy, shelter and many more
uses. It is a remarkable tree giving more than 300 products.
A unique feature of the coconut palm is that its ability to provide main food components
namely carbohydrates, proteins, lipids, dietary fiber, vitamins and minerals. These main food
components are obtained from tender or mature nuts or from the tender inflorescences
manipulated to exudates sap as given below:
i. Nut water - Sugars, amino acids, fatty acids, vitamins, and minerals
ii. Inflorescence sap - Sugars, amino acids, vitamins and minerals
iii. Mature kernel - Fatty acids, proteins, carbohydrates, dietary fiber,
vitamins and minerals

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
The coconut kernel based products produced in major coconut producing countries can be
grouped into two broad categories as traditional marketable products and value added new
products:
Coconut- kernel based products
Traditional coconut products: New value added products:
Copra Virgin coconut oil
Coconut oil Coconut paste/cream
Desiccated coconut Coconut milk powder
Coconut cheese
Coconut yoghurt
Coco powder
Among the newly emerging value added products, the newest high value product, which is
gaining popularity in the Western world, USA and other developed countries, is the Virgin
Coconut Oil (VCO). Various literature and medical reports available on VCO today consider
it as a healthy oil, nutritive oil and widely used in pharmaceuticals, nutraceuticals,
cosmoceuticals. It also consider as an oil with therapeutic properties. High value market for
VCO presently exist as a food supplement, body moisturizer, carrier for aromatherapy, a hair
conditioner, and has generated great deal of interest among coconut processing sector as well
as coconut growers today.
Unlike oleo-chemical manufacture, VCO manufacture is a simple process, which can be done
at micro, medium, or as a large-scale industry by using simple methodology. In Sri Lanka
simple VCO extraction machines are available today for all three levels of manufacturing
processes.
What is Virgin Coconut Oil?
VCO is coconut oil extracted from the coconut kernel, closest to its natural form without
subjecting to any chemical or physical changes. Coconut oil extracted by wet or dry
processing devoid of free fatty acids, (less than 0.1%) and has a sweet coconut flavor.

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
Composition of Virgin Coconut Oil:
Percentage
Caproic acid (C6:0)
0.7
Caprylic acid (C8:0).
4.6 - 10.0
Capric acid (C10:0)
5.0 - 8.0
Lauric acid (C12:0)
48 - 52
Myristic acid (C14:0)
16 - 21
Palmitic acid (C16:0)
7.5 - 10
Stearic acid (C18:0)
2 - 4
Oleic acid (C18:1)
5 - 10
Linoleic acid (C18:2)
1 - 2.5
Linolenic acid (C18:3)
Trace amount
Source: Bawalan et.al.(2006)
Specific characteristics of virgin coconut oil:
Virgin coconut oil has light viscosity, a clear water appearance and free of particles. It
solidifies below 250C. It has a mild coconut flavor and aroma, very long shelf life and high
resistance to oxidation. It is stable at high cooking temperatures; hence, free radical formation
at high temperatures does not occur due to saturation.
Standards of virgin coconut oil:
Properties
FAO Specifications
Moisture and volatile matter
0.20% max.
Free Fatty Acid (as Lauric Acid)
0.2% max.
Peroxide value
3.0 meg/Kg oil max.
Food additives
Not permitted
Colour
Colour less
Contaminants
Matter volatile at 105 0 C
0.2% max.
Heavy metal
Mg/Kg max.
Iron (Fe)
5.0
Copper (Cu)
0.40
Lead (Pb)
0.10
Arsenic (As)
0.10
Odor
Normal nutty smell
Source: Bawalan et.al. (2006)
Methods of processing virgin coconut oil:
Methods of processing VCO vary with the volume of processing as well as the equipment
and accessories used for extraction.

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
Fig. 1: Different methods of processing of VCO for household/industrial uses:
Fresh Mature coconut
Virgin coconut oil can be extracted from fresh comminuted coconut meat or from fresh
coconut milk. The choice of technology depend on the scale of operation, machinery
available, and the ability for investment.
a) Dry Processing
In this method dehusked mature coconut are first selected. For easy drying the fresh kernel is
grated using a electric grater or deshelling, brown testa is removed and pulverized in a
suitable coconut shredder. Grated or comminuted coconut meat has to be dried immediately
in a suitable dryer such as solar dryer, forced drought tray-type dryer or in a vacuum dryer
temperature not exceeding 700C. Solar drying is the cheapest method for drying, if regular
long duration of sunlight is available. When hot air dryers are used, drying process can be
completed within 3-4 hours but involves high initial investment.
For extraction of VCO low pressure oil extraction equipment developed by the National
Engineering Research and Development (NERD) Center, Sri Lanka as well as cold pressed
expeller developed by the Coconut Processing Research Division of the Coconut Research
Institute are used in Sri Lanka. The vertical screw type expeller and hydraulic jack type oil
Dry processing
Wet processing
Grated/crushed coconut
Coconut milk
Dry Coconut
High pressure
expelling
Desiccated coconut
route
Cold pressing
Natural
fermentation
method
Chilling and
centrifugation
Grated coconut

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
press developed by the NERD Center are most suitable for small and medium scale VCO
production.
Fig. 2: Flow Diagram of dry process of virgin coconut oil expelling:
Fresh Coconut Scraped coconut
VCO production at household level or by village level operation can be done using this
method.
Dry until moisture
level around 5%
Microwave drying
Oven drying
Solar drying
Residue
Press using a hand-pressing
machine, Screw type or
hydraulic jack type oil press
Virgin Coconut oil
Heating below 70 0 C in a hot
water jacket and filtering
……..filtering
For confectionary
Virgin coconut oil

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
Fig. 3: Medium and large scale processing of VCO by dry Process:
Fresh Coconut
Source: Baensch (2003)
Deshelling
…….
Paring or removing the
brown testa
Soaking in NaoCl distilled
water (Organic VCO in hot
water
Clear coconut kernel
without taste
Pulverize kernel
Crushed coconut
Drying in a vacuum dryer or
fan forced oven below 600C
Processing in a cold press
expeller below 600C
Expelled VCO
Residue after double expelling
White low fat residue
………………….CO
Grinding
Coco powder
VCO ( crystal
clear oil)
Fine filteration in a filter
press

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
Main steps in dry process of virgin coconut oil extraction:
i. Selection of nuts - Fully mature nuts are selected.
ii. Splitting and grating - For small scale manufacturing process (100 - 300 nuts)
grating is done using a motorized coconut grater.
De-shelling, paring
and crushing - For medium and large scale manufacturing process
(1000 - 10000 nuts) after de-shelling brown testa
is removed, washed in hot water and crushed in
a medium or fine shredder.
iii. Drying at low
temperature - Grated or shredded coconut then dried to a moisture
level around 5% in a indirect hot air dryer, sun dryer,
hot air vacuum dryer, force-drought hot air oven
maintaining the temperature below 70oC. This may
require 3 - 4 hrs. for one batch to dry. (grated or
comminuted coconut meat should be dried immediately
to prevent microbial contamination).
iv. Extraction of Oil - Small-scale extraction is done in a vertical screw type
or hydraulic oil press manually.
Large scale extraction is done in a electrically
operated screw type cold press expeller which has an
input capacity of 30 - 50 kg per hr.
v. Drying - When oil is expelled in a screw type manual press
drying of oil is necessary to remove residual moisture
in addition, to increase the shelf life of VCO. Drying is
done keeping in a jacketed water bath for 30 - 60
minutes.
vi. Filtration - After settling of oil for 1-3 days filtration is done using
3-4 layers of filter cloth.
Oil extracted in a cold press expeller need not to dry
however, very fine particles of coconut meat come with
oil. Therefore, extracted oil is collected into a tank and
allowed to settle for three 3 - 4 days before filtration.
Then oil is filtered in a filter press to get clear VCO.

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
a) Wet processing:
In the Philippines and Indonesia, modified natural fermentation method is used for the
processing of virgin coconut oil. Advantages of modified natural fermentation method are
that it has the lowest labour requirement and least energy usage. Fermentation of coconut
milk is the most critical step in this method. To obtain good yield of VCO the fermentation
container will be placed in an area where relative humidity is 75% and the temperature is 35
to 40 0C.
b) Fig. 4: Natural fermentation method of processing VCO:
Coconut milk
Natural Fermentation
For 16-24 hrs at 35-400C
Phase separation Separated oil
Filtration
Coconut curd
Oil drying
Clear VCO

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
c) Fig. 5: Cooling method of VCO production:
(Triple)
(triple)
impure
Cooling grated
Coconuts
< 10°C
Chilled Water
Extraction
of fresh grinded
Coconuts
Skimmed Coconut Milk
(SCM 3)
Wet Oil Cake
(Oil-Sludge-Fibre)
Grinding Coconuts
Fresh Coconuts
Hydraulic Pressing
of grated + chilled Coconuts
Warm Water -
Extraction
with Hydraulic Press
Wet Coconut Oil
With Sludge
impure Fibre
Washing Fibre and
launch off water
with Spin dryer
Dry Fiber in Solar
Drier
Pure Fibre
Filter
Virgin Coconut Oil

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
Coconut flour and Coconut flour based products:
The whitish residue remained after extracting coconut oil from the cold press is hygienic and
suitable for human consumption. Coconut flour is obtained from the coconut residue (grated
and dried coconut kernel or comminuted fresh coconut meat) after extracting coconut oil.
Table 1: Nutrient composition of coconut Flour
Component
Percentage
Moisture
Ash
Fat
Protein
Fiber
carbohydrates
4.20+/-0.23
5.96 +/-1.19
8.42 +/-0.87
21.65 +/-0.06
10.45 +/-2.5
59.77 +/-3.32
Source: Annual Report (2004)
Utilization of defatted coconut kernel residue as raw material for preparation of fiber-
enriched food products:
Defatted coconut flour (DCF) obtained from the residue after the extraction of virgin coconut
oil has potential application in high protein-fiber enriched food products. Defatted coconut
flour can be used in the preparation of fiber-enriched biscuits. In this, wheat flour (WF) is
fortified with DCF in varying proportions (w/w, 0, 10, 20, 30, 40, 50, 60, and 70%) to
prepare a series of blends for biscuit dough. DCF can be used to substitute WF up to a level
of 40 % without affecting the overall quality. Based on the sensory evaluation study, it has
been found that the DCF substitution up to 40 % is more consumer acceptable.
Jellies, Yoghurt, Spread Cheese, and Beverage from Coconut Skim Milk:
Skimmed Coconut Milk (SCM) is prepared by pressing chilled coconut with the use of a
hydraulic pressing machine. Three extractions are done for the same coconut meat sample.
The first extraction is done without using water and other two extractions were obtained each
with (5:1 w/v) cold water. The SCM obtained can be used for preparation of jellies, yoghurt
and spread cheese of good quality. Pasteurization of SCM is carried out at 75oC for 5
minutes. To improve the consistency of jelly and yoghurt and to stabilize the oil-in-water
emulsion “stabilizers” are added to the SCM.
Stabilizers: Locust bean starch, rice starch, cornstarch, cassava starch, pectin, carboxyl
methylcellulose (CMC), and gelatin.
Flavors: Cinnamon, cloves, vanilla, and other spices are suitable for flavoring. Fruit juice
concentrate also used for flavor the product.
Starter cultures: used for yoghurt are Streptococcus thermophiles, Lactobacillus acidophilus
and species of Bifidobacter. Incubation temperature is 42 oC for 5-6 hours.

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
Starter cultures: used for spread cheese are Lactococcus lactis subsp. lactis and
Lactococcus lactis subsp. cremoris. Incubation temperature is 42 oC for 12-16 hours.
Preparation of Yoghurt:
Skimmed coconut milk is mixed with non-fat milk powder in the ratio of 1:1. Then stabilizers
(1%) and flavours are added. The mixture is homogenized at 15000 rpm for 5 minutes.
Pasteurization is carried out at 75oC for 5 minutes. After cooling the content to 42oC,
inoculation is carried out with 2% starter culture. Then the mixture is filled into cups and
incubated at 40 oC for 5 - 6 hours. Cups are stored at a temperature less the 10 oC.
Nutritional information of coco-yoghurt:
Moisturepercentage - 85.7
Fat% - 3.5
Protein% - 3.5
Solid Non-Fat% - 10.8
Preparation of Jellies:
Skimmed coconut milk is added with stabilizers and flavors. Then the mixture is
homogenized at 15000 rpm for 5 minutes. Pasteurization is carried out at 75 oC for 5 minutes.
Then the mixture is filled into cups and stored at refrigerated conditions. After the jelly is set
it is ready for consumption.
Preparation of Spread Cheese:
Pasteurized skimmed coconut milk is cooled to 60oC and it is mixed with white pepper and
non-fat dry milk powder. Then the mixture is homogenized at 12000 rpm 30+2 oC for 5
minutes. It is further cooled to 40oC and inoculated with 5 % lactic starter culture. It is
allowed to stand for 15 minutes and 2 % salt is added. Then the mixture is filtered through
cotton cloth and pasteurized at 75oC for 5 minutes. The mixture is cooled to 40 oC and 0.003
% (w/v) rennet is added. It is incubated at 42oC for 3 hours for coagulation. The curd is
mixed using a mixer. The mass is transferred to a white cotton cloth and allowed to drain for
4 hours at 5+2 oC. The mass is mixed with 0.5 % antioxidant. The coconut spread cheese is
poured into sterilized glass bottles and stored under refrigeration.
Nutritional Information:
Moisture (percentage) - 78.8
Crude Protein (percentage) - 13.1
Crude Fat (percentage) - 2.8
Crude Sugar (percentage) - 2.0
Salt (percentage) - 2.0
Mineral (percentage) - 1.3
pH - 5.1
Source: Baensch (2003)

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
Skimmed Milk Beverage
Formulation of a skim milk beverage:
(a) Preparation of coconut skim milk
Coconut kernel is grated (1500 g) and chilled at 5 + 2 oC overnight. Coconut milk is extracted
with the use of a hydraulic pressing machine without addition of water. Two other extractions
are done with 300 ml each chilled water.
(b) Fig. 6: Preparation of skim milk beverage concentrate
Coconut skim milk
Pasteurization
(Heat mixture at 90 0C for 30-min. stir occasionally to prevent curdling)
Cooling (40 0C)
Homogenization
(12000 rpm for 5 minutes)
Addition of sugar
(Heat the mixture to 60 0C then add 1 part sugar to 1 part milk heat further to 80 0C)
Addition of flavours
(Cool to 60 0C then add 0.5 % flavor)
Bottling
Pasteurization (at 70 0C for 15 minutes)
Preservatives and stabilizers:
0.035 % preservative (sodium metabisulphate) +0.5 %flavour
1% stabilizer (carboxy methylcellulose) +0.5 %flavour
The pH and mineral content did not vary much between coconut milk and coconut skim milk.
However, moisture and protein contents increase considerably in coconut skim milk and this
is obviously due to removal of fat, one of the main components of coconut milk. Thickened
skim coconut milk can be used as a coffee whitener.

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
Coconut Beverages:
Coconut water is the endosperm of coconut and it is an important beverage providing energy,
minerals, amino acids, and small amount of vitamin C and B. An average drinking coconut
can provide approximately 15-16 g of sugar and 64 K cal of energy. Energy mainly comes
from sugar. Fifty percent of the sugars in nut water are fructose sugar and the reminder is
sucrose and glucose. Fructose sugar in tender nut water does not increase the blood
sugar/glucose level in diabetics as much as glucose and sucrose. Tender nut water is rich in
amino acids such as glutamic acid, arginine, aspartic acid and alanin. Coconut water is rich
in K and low in sodium.
Nutrient Content in Coconut water:
Nutrients
Value per 100g of edible portion
Energy (K cal)
Water(g)
Protein(g)
Fat(g)
Ash(g)
Carbohydrate (by difference) (g)
Fiber, total dietary fibre(g)
Sugars, total(g)
Calcium (mg)
Magnesium(mg)
Phosphorous(mg)
Potassium(mg)
Sodium(mg)
Iron(mg)
19.0
94.99
0.72
0.20
0.39
3.71
1.1
2.61
24
25
20
250
105
0.29
Source: USDA National Database (2004)
Uses of coconut water in the food industry:
i. Tender nut water
Processed tender nut water has many advantages over synthetic beverages in the absence of
any coloring agents, preservatives, additives.
In the food industry sterile nut water with prolong shelf-life is obtained by heat sterilization
or micro filteration and packed in convenient packs like tetra packs or stand up poches to
make it ready to serve beverage. Tender kernel of drinking nuts is rich in essential fatty acids
and it can be processed into coco jam. Coconut water is a light suspension of free nuclei. A
pure preparation of such nuclei may have prospects for pharmaceutical uses.

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
ii. Mature nut water
Mature nut water contain 2 - 3% sugars as carbohydrates, minerals mostly potassium, 0.5%
protein, 0.2-0.4% fat, amino acids, vitamins and small quantities of growth hormones. It is
an excellent medium for microbial growth because of its richness in essential nutrients.
Processing of mature nut water for beverage purposes needs filtration and centrifugation to
remove suspended material and oil. To improve palatability and to maximize utilization of
coconut water supplementation of fruit pulp or lime juice to processed nut water is desirable.
Microbial processing of nut water into fermented food products:
Microbial organisms are employed to process nut water into high value food products. The
growth of microorganisms and to produce secondary metabolic products the culture medium
should contain C.H,O,N,S,P in micro-quantities and some micronutrients, vitamins and
amino acids. Coconut water is rich in all these essential nutrients for microbial growth.
Several microbial processing technology employed in food industry are given below:
Mature or tender nut water Saccaromyces cerevisiae Coconut wine (12% ethanol)
+
Added sugar
Acetobacter aceti
Mature nut water Vinegar (4% Acetic acid)
Mature nut water Acetobacter xylinum Nata de coco (Cellulose)
In the Philippines and Indonesia, coconut water is processed into nata de coco by industrial
scale bacterial processing.
Nata de Coco is a product having hard jelly type texture made out of coconut water. To
prepare Nata de Coco, mature nut water is mixed with sugar and ammonium sulphate (0.5
and kept overnight). Then acetobactra xylinum culture is added to the mixture and the
mixture kept in a tray for 07 - 10 days. Tray should be covered after about a week, it will
form a clear gel of 1.2 to 1.5 cm thickness with a sour taste. Then the gel is washed several
times in water to get rid of sour taste and then dipped in hot water and out into cubs. These
cubes then dipped in sugar syrup flavored and colored as desired. The gel formed by the
bacteria is found to be low in calories, high in fiber and low in cholesterol. It is nutritious
and good for dietary purposes.
References
1.Annual Report (2004). Report of the Coconut Processing Research Division. Annual
Report of the Coconut Research Institute of Sri Lanka
2.Bawalan D.D., Champan, K.R.(2006).Virgin Coconut Oil, Production manual for micro
and village scale processing. FAO Publication.

Proceedings of International Coconut Summit, 7th -11th May, 2007, Kochi, India.
3.Baensch,W.,Yalegama,L.L.W.C.and Jayasundera,J.M.M.A. (2004), New Technologies
of coconut processing. Part 1-Process for defatting coconut meat (wet process).
Proceedings II of International Conference of 75th Anniversary of Coconut Research
Institute of Sri Lanka.
4.Baensch,W.,Yalegama,L.L.W.C.and Jayasundera,J.M.M.A. (2004), New Technologies
of coconut processing. Part 1-Process for production of Virgin Coconut Oil and Low Fat
High Protein Coco Flour from coconut kernel. Proceedings II of International Conference
of 75th Anniversary of Coconut Research Institute of Sri Lanka.
5.Baensch, W.(2003). Personal communications.
6.Jayasekera, C. (2004).A Selection of Prospects for Improvement, Diversification and
Value Addition for Traditional and Novel Coconut Products. Proceedings I of
International Conference of 75th Anniversary of Coconut Research Institute of Sri Lanka.
7.Ranathunga, Y.Y.M. ,Malini,K and Kalpage,N.(2001). High quality coconut oil
production at domestic and cottage industry levels. Internal Research
Presentations,National Engineering Research & Development Centre.16-17,November,
Colombo, Sri Lanka
8.Ranathunga,Y.Y,M.,Malini,K.(2004). Production of virgin coconut oil at cottage level
using Rotary drier, Proceedings of research seminar of 30th anniversary of the NERDC of
Sri Lanka.
9.USDA National Database for standard reference, Release 16-1 (2004).
http://www.nal.usda.gov/fnic/foodcomp/search/