Coconut Processing Pdf
Shameka Roessler
In Sri Lanka there are about ten mid-size firms each running 50,000 to 100,000 coconuts per day. Some use the name Coco Lopez to describe cream of coconut which they produce. These firms are larger than processors in the Dominican Republic, where they typically run 20,000 to 50,000 nuts per day. However, there are no big processors like they have in the Philippines, where typically they run 300,000 to 800,000 coconuts per day.
The yield (or recovery) of coconut cream in Sri Lanka is much higher than is seen in the Philippines. 65% to 70% is common in Sri Lanka, compared to 45% to 55% in the Philippines. This is at least partly due to blanching the meat at 80C to 90C temperature ahead of the screw presses.
Much of the cream of coconut produced in Sri Lanka is used to produce cold pressed coconut oil. Centrifuges are used to separate this oil from the coconut cream. Recently the popularity of cold pressed coconut oil has increased significantly.
The brown coconut peel and trim rejects are supplied to alternate processors. These dry this waste into copra, which is used in the production of virgin coconut oil. (The same practice is followed in the Dominican Republic.)
Note that traditional virgin coconut oil is expelled from copra (dried coconut meat). Vincent is not involved in that process. It requires that the fat in the copra be squeezed hard enough for it to flow out as liquid oil. Anderson International pioneered the expellers used for this purpose.
Typical of the industry world-wide, the coconuts (frequently referred to simply as nuts) arrive at the plant with the husks having been removed at the plantation. The outer brown shells are removed by pressing them, hand held, against high speed rotating snag-tooth drums. The drums are narrower in Sri Lanka than those we have seen in the Philippines. This contrasts to the use of machetes in the Dominican Republic. (We have also seen processing in the Dominican Republic which involves blanching the entire nut, on trays in canned food pasteurizers, followed by spooning the softened meat out from the shells.)
After shelling, the kernel is the part that is left. The norm in Sri Lanka is to peel the brown skin from the kernel. This is in contrast to shredding and processing the entire kernel, sometimes done in the Dominican Republic.
The next steps are to blanch, shred, and run the meat through a screw press. Single pressing of the meat is used in Sri Lanka and the Philippines, in contrast to triple pressing in the Dominican Republic.
All but two of the Sri Lankan processors use Bepex (Rietz) presses, or local Wanigasekara presses which show evolutionary development from the Rietz machines. An exception to this is our customer, who uses modern Vincent screw presses. And there is one processor who uses belt presses for expelling the cream of coconut.
Coconut water is a refreshing drinks which also hygienic and nutritive. The white flesh is a calories rich extensively used for cookery in South India. From grated wet coconut kernel good quality oil as well as protein and carbohydrate can be extracted to prepare coconut honey. Undesirable flavour changes in desiccated coconut is due to oxidative rancidity of the oil. The residual cake after the oil has been extracted is used as cattle food.
The dried coconut meat is known as copra and is the source of coconut oil, which is used in enormous quantities for making fats for baking and confectionery. An important product used in the chocolate and confectionery industry is desiccated coconut. The nut is removed from the hard shell and the thin brown rind pared off. This must be very thorough or the finished coconut will be contaminated by flecks of brown. The pared nuts are then washed free of milk and skin residues and put through shredding machines, which give a milled product of varying degree of fineness. After shredding, the ground meat is subjected to a steam or hot water treatment to destroy salmonella and lipases and to reduce bacteria counts to low levels. The pasteurized meat is then dried on wire mesh belts by means of hot air, which reduces the moisture content to less than 4%. The critical moisture level of desiccated coconut is 5% and the product should be well below this to ensure good shelf life.
After drying, the desiccated coconut is put through a multiple sieving operation to produce the four main grades. Extra fine, macaroon (fine), medium and coarse. A variety of other coconut products is available to the chocolate and confectionery trade such as, moist white sweetened coconut, toasted coconut, creamed coconut and tenderized coconut.
Top quality desiccated coconut should be white in colour, free from foreign matter, and uniform in granulation against standard, and the expressed oil should have a free fatty acid content of less than 0.1%.
Extraction of Coconut Oil
The coconut is the most extensively grown and used nut in the world. About 10 million people in India and several million of people in other tropical regions depend on the coconut plant for their livelihood. India is the third largest coconut producing country of the world with an area of about 1.12 million hectares contributing to 18% of world production. India produces about 6000 million nuts annually. A whole coconut consists of 50% husk, 15% shell, 25% meat and 10% water.
The coconut shells contain 34% cellulose, 36% Lignin, 29% pentosans and 1% Ash.
Traditional method:
The coconut oil is traditionally extracted from copra. The copra can be obtained by separating the coconut meat from the whole coconut shell followed by sundrying and smoke drying for about 6 to 8 days. The copra is then chopped to small sizes and cooked by heating the small pieces of copra in a cooker for about 30 mins. The oil is squeezed out from cooked copra by an expeller and then filtered by a filter press.
Coconut Chips*: Coconut chips, the thinly sliced crispy coconut meat which may be sweetened or salted and may come in handy as a ready -to- eat snack food. It was prepared by slicing the coconut meat of eleven to twelve month old nuts thinly into strands, soaked in syrup, drained and dried in a dryer or oven.
Coconut Crisps*: Coconut crisp is prepared from the young coconut endosperm of nine to ten month old nuts. It is white in colour, has pleasant coconut flavour and does not leave any fibrous feeling after taste. It was processed by slicing the meat into 0.6-0.7mm thickness, blanched in boiling water, cooked in light syrup and then dried which is considered as a high energy food and of a good quality product.
Roasted young coconut*: Roasted young coconut was prepared by a process in order to sweeten its water and tender meat as well as to enhance their flavour. The process consisted of preliminary steps and the nuts were boiled in a solution (2% sodium meta
bi- sulphite) for 20 min, dried and burnt for finishing touch and it was exposed to the fire for a minute or until the shell itself showed signs of burning. The fruit was kept at room temperature for 3 days or in the refrigerator for larger storage.
Honey roasted coconut*: Honey roasted coconut, a sweet, thinly sliced crispy coconut meat, eaten as a snack food. Sliced matured coconut meats was mixed with honey sugar, margarine, sweeten condensed skim milk, molasses and salt and dried in oven for half an hour. Then it was agitated frequently for 15 min until it become crispy, cooled and packed.
Dehydrated sweet coconut*: Young coconut meat was used for preparation of dehydrated sweet coconut. The coconut meat was washed with water and then soaked in coconut water, again washed with clean water. The meat was cut into pieces mixed with refined sugar and water in the ratio of 6:3:1 and boiled for 1 h or until it is dried, cooled and packed.
Dehydrated coconut chutney**: Dehydrated coconut chutney using simple hot air drying technique was developed. It reconstitutes well in cold water and had all the characteristics of fresh chutney. The product had a shelf life of 3 months at 37oC and 6 months at ambient temperature when packed in flexible pouches.
Coconut milk**: Coconut milk refers to the milky fluid, freshly extracted from the coconut kernel with or without added water and coconut cream to the high-fat cream-like material obtained from the coconut milk by either gravitational separation or centrifugation
Coconut milk was prepared by blending skim milk powder with coconut milk, obtained from freshly grated coconut and pasteurized at 70-72oC for 10min. It contains 6 percent skim milk powder and 9.65 percent total solids (Agrawal, et al. (1991). Coconut milk, a generic term for the aqueous extract of the solid coconut endosperm, plays an important role in the cuisines of South East Asia as well as in other parts of the world.
Fermented beverage from coconut skim milk using different combinations of coconut skim milk and non-fat dry milk and the culture used was Lactobacillus bulgaricus. Based on sensory evaluation, 50 per cent of coconut skim milk: 50 per cent of non- fat dry milk ratio was the most acceptable formulation. The ready-to-drink fermented beverage concentrate (diluted at 1:3) contains protein (1%), fat (0.74%), sugar (18.70%) and water (79.25%). The fermented beverage concentrate was found to be stable even after 2 months of storage and coconut skim milk can be utilized successfully for the processing of cultured milk.
Coconut cream: The concentrated milk extracted from fresh matured coconuts can either be used directly or diluted with water to make various curry preparation, sweets, desserts, puddings etc. Processed and packed coconut cream had a
shelf life of six months and once opened it should be stored in refrigerator for subsequent use. Coconut cream, a concentrated form of coconut milk, which is a convenient product prepared from mature and fresh.
Coconut syrup: Coconut syrup, a translucent, free-flowing liquid was prepared by cooking coconut milk with an equal amount of refined sugar and di-sodium-phosphate equivalent to 0.25 per cent of the volume of the milk, until the mixture attained a TSS content of 68-70 per cent. The hot mixture was poured in sterile containers and sealed hermetically. It was used as a topping for bakery products or as a mixer in alcoholic drinks or may be diluted in water and used in cooking rice cakes and other delicacies.