AU747432B2 - Coconut processing - Google Patents

Description

WO 99/29188 PCT/AU98/01011 I 1

TITLE

Coconut processing.

FIELD OF THE INVENTION THIS INVENTION relates to the processing of coconuts and in particular to the generation of copra and other coconut products.

BACKGROUND

Copra is the dried meat of a coconut. Coconut oil is pressed from copra. The oil can be used in the production of soap, margarine, detergent and other products. The cake remaining after pressing, called coconut-stearin, can be used as animal fodder. Copra is produced by drying coconut meat either in the sun or by use of hot air or kilns. Drying allows the coconut meat to be kept for longer periods, allowing transport from plantation to processing plant.

Coconut meat needs to be extracted from the coconut.

The coconut has a rind, over, typically, 2.5 to 5 cm of fibrous husk which surrounds a woody shell containing the meat. Traditionally the coconuts are husked, opened by splitting or cutting the woody shell, and the meat then spooned out for drying, or dried in the woody shell to cause the meat to shrink away from its woody shell and release from it. Some drying of the meat is over fires, or, typically, by passage through a tunnel of hot air. The fibres of the husk, called coir, may be made into mats, ropes, brooms and other products. The WO 99/29188 PCT/AU98/01011 2 woody shell can be carbonised for use as a fuel or otherwise used for other purposes.

The processing of coconuts is labour intensive in that it is a manual process. As such it faces problems with hygiene. The typical drying process exposes the coconut meat to contamination, being exposed also to rain and dirt when sun dried, being subject to degradation by excess heat in kilns, and additionally by smoke when dried over fires. Drying must be effective to reduce moisture content to less than 10% otherwise moulding will spoil the copra.

Generally coconut production around the Pacific is operative to supply copra into Europe where the oil is extracted and goes into the production of a range of products, with the coconutstearin used as a cattle food. The husk and woody shell is typically left at the plantations and is largely wasted. The copra is transported as chunks or half shells. In this form about five tonnes maximum can be packed into a standard twenty foot container.

OBJECT OF THE INVENTION It is an object of the present invention to provide improvements in methods and apparatus for the processing of coconuts, which improvements reduce labour inputs, provide greater control in production, and reduce the degradation and contamination which is noted above. Additional advantages will be realised in preferred forms, as will become more clear herein below, such as in Provision of a product which is more efficiently transported from the point of production to end users.

NATURE OF THE INVENTION According to one aspect of the invention there is provided an apparatus for processing coconuts, said apparatus including:spaced conveyor members each having a plurality of inwardly directed engagement members adapted in use to supportingly engage opposite sides of a coconut located therein; a splitting station aligned with a travel path of said conveyor members, in use, to sever coconuts into portions as said coconuts are conveyed through said splitting station; a meat removal station having high pressure water jets oriented to direct high pressure water into an exposed interior region of severed coconut portions supported on respective said conveyor members to remove coconut meat from said severed portions; and, a a disengagement station wherein severed coconut portions are disengaged from respective engagement members.

In a preferred form the method is one wherein the husks are collected and used in generating heat for drying the meat by use of at least the husk 20 as a fuel. The method may additionally be operated to remove the woody shell from the husks to enable it to be separately carbonised as a byproduct.

Further the method may use water jets to separate coconut meat from it l woody shell and/or the husk from the woody shell. In a refined form the method may be operated to remove the hard skin from the coconut meat so 25 as to enable production of desiccated coconut.

According to another aspect of the invention there is provided a method of processing coconuts comprising the steps of:supporting coconuts between spaced conveyor members having a plurality of inwardly directed engagement members to engage opposite sides of said coconuts; conveying said coconuts through a splitting station to sever said coconuts into portions; and, removing coconut meat from said severed portions whilst supported on respective conveyor members by directing a high pressure waterjet into a central region of exposed coconut meat in said severed portions to dislodge said coconut meat from a respective coconut shell.

Preferably the apparatus is one wherein there is a burner operable to heat the drier, using the husks and/or woody shell of the coconuts left after the meat is removed. Ideally the apparatus is one wherein the coconut divider which sections the coconuts utilises one of a circular saw, band saw o or water jet. Preferably the dryer converts the meat to copra using a conventional fluidised bed dryer or jet dryer as will be known to those skilled in the drying art, preferably operating in the range 90-120°C. The copra is preferably reduced to a compacted, granular material for transport. If the 20 material is reduced to a compacted, dried granular material, about twelve tonnes might be packed into the same twenty foot container.

l. l• •o WO 99/29188 PCT/AU98/01011 In a preferred form the apparatus for the processing of coconuts effects the removal of the coconut meat by the use of high pressure water jets. These devices are well known to those skilled in the art and any of the stock items delivering a jet suited to the present s application might be bought into use in the present invention. The sectioning with water jets might utilise a pulse into the hollow of a coconut section, the pulse removing the coconut meat as a shell, the jet working through the meat and then taking the line of least resistance, working out around the inside of the woody shell to effect detachment of the coconut meat. Alternately, to avoid the task of repetitively switching or pulsing the high pressure jet, the jet might be operated continuously. In this mode, the jet cuts from an edge, into the meat and back to the woody shell where it again takes the line of least resistance working out between the coconut meat and the woody shell to effect its removal.

In another preferred form of the apparatus for the processing of coconuts the husk or coir is preferably separated from the hard woody shell also by use of a water jet. The coconuts or the remains of the coconut portions, from which the coconut meat has been removed, may passed beneath a jet, coir side exposed to the jet, and again the jet will cut to the woody core whereat it will take the line of least resistance, working out beneath the coir, over the hard woody shell, to effect a separation of the two.

WO 99/29188 PCT/AU98/01011 6 In yet another preferred form of the coconut processing apparatus, the coconut meat which may be removed as a shell can be rolled or otherwise treated to flatten or otherwise form it to enable the skin which exists around the outer side of the shell to be planned off or otherwise removed. When this skin is planned off or otherwise removed, the thus prepared coconut meat may be dried, to be used as desiccated coconut. The shavings from the planner may be fed to the copra producing section of the apparatus.

DESCRIPTION OF THE DRAWINGS The invention will now be described with reference to various preferred embodiments which are described herein with reference to the accompanying drawings wherein: FIGS. 1 and 2 show schematically, in a generalised plan view and elevation, the components of a coconut processing plant which is in accordance with the present invention; FIG. 3 shows in an edge elevation, a detailed view of an aspect of coconut processing apparatus which effects the processing indicated in FIG. 1; FIG. 4 shows an alternate form of feeder to deliver coconuts from a silo for processing in accordance with the invention; FIG. 5 is a plan view of an alternate means of an arrangement by which coconuts may be delivered for sectioning into coconut portions for processing in accordance with the invention; WO 99/29188 PCT/AU98/01011 7 FIGS. 6 and 7 is seen detail showing how the coir might be removed from its woody shell, in accordance with the invention; and FIG. 8 shows in elevation a mechanism by which coconut meat shells might be processed to remove their skin, in accordance with the invention.

PREFERRED EMBODIMENTS In FIGS. 1 and 2 a holding container, silo, storage hopper, or bin 10 (hereinafter referred to simply as a bin for convenience) may be used to retain, hold or store a quantity of coconuts which are to be processed. The coconuts may be fed or dispensed from the bin 10 by any suitable means, as will be known to those skilled in the art, or otherwise delivered to, a suitable delivery mechanism, transporter, or conveyor 11 (hereinafter referred to simply as a conveyor for convenience) which translates, moves, or carries them to a processing station, zone or nip between, in this embodiment, two co-planar wheels 13,14 (hereinafter referred to simply as the nip for convenience), where a coconut, such as coconut 12, may be supported, held or engaged thereby, with suitable retention means or attachments, holding devices or hooks 15, 16 (simply referred to herein below as hooks for convenience) projected therefrom or mounted thereon, which may be pressed or driven, at the nip, into the husk of a coconut, fed thereto, so as to retain or hold it WO 99/29188 PCT/AU98/01011 8 firmly between the wheels. The conveyor 11 may be a cup conveyor on which coconuts are oriented longitudinally to advance them to a divider, portioning or sectioning device where they are sectioned longitudinally into portions. An alternate mechanism by which to bring the coconuts to a sectioning device is described in greater detail below. A cleaving, cutting or splitting device, such as a saw or water jet, located at 18, cuts or splits the coconut into portions, preferably hemispheres, which are parted or separated, 19,20, as the wheels turn to carry the coconuts through the nip. Water jets located at 23, may be used to strike the meat in the respective halves 24, 25, to cause removal of the meat from its woody shell, with the meat collected on a suitable conveyor 26 for transport ideally to a hammer mill 40 or the like and then on to dryer 41 via conveyor 27 or the like.

The husks can be collected on a conveyor 28, after removal from the wheels 13, 14 by levers, prongs, ejectors or ramps 29, 30 which enter or pass under the husks, to release or disengage the husks from their supporting hooks. The collected husks can be bought to a high pressure water jet at 35, on a suitable conveyor 31, passing or carrying them past the water jet where the woody shells may be removed by action of the jet, and dropped onto a conveyor 36 for passage or delivery to a granulator, roller or mill operable to reduce them, ideally to granular form, if desired, and a carbonisation chamber to convert the woody shell material to carbon. The husks can be WO 99/29188 PCT/AU98/01011 9 collected on a conveyor 37 for delivery to a furnace. The two wheels may be driven by any suitable means, as will be known to engineers in the art, such as a chain 40, powered by a drive sprocket 41, looped around sprockets 42, 43 on the respective wheels. The bin 10 may incorporate a vibrator or shaker, as will be known to engineers in the art, powered by motor 44 and connected at 45 to a conical base 46 with outlet 47 from which coconuts may drop onto conveyor 11. A chute or sluice 48 may be provided as a means by which to carry away any waste produced at the portioning or slicing station. The coconut meat remover 23 may feed two water jets 49, 50, oriented appropriately to aim into the hollow of the coconut portions as shown.

In the particular embodiment of FIG. 2, the coconut husks on conveyor 31 are carried or conveyed, open side down, beneath an overhead engagement means or stabiliser 52, which may be a belt or the like, typically mounted around rollers as will be known to those skilled in the art, to carry or lead the husks up to and past a jet 53 which is operative to remove the coir from the woody shell.

In the particular embodiment of FIG. 3 is seen the nip between wheels 13, 14 in side view. The rims of the wheels are ideally concave, to present faces 38, 39 which complement the shape of a typical coconut. The hooks 15,16 may be arrayed over the surfaces 38,39 to ensure good engagement with and support to the coconuts fed thereto. As a coconut can be typically from 30-40 cm WO 99/29188 PCT/AU98/01011 on one dimension, and 25 to 35 cm transverse to it, some accommodation to size variation is desirable. In this regard the wheels may have a deformable rim, or, one or both wheels might be mounted on movable axles which are biassed to close the nip to sufficiently engage the coconuts, but movable to accommodate larger or smaller nuts.

In the particular embodiment of FIG. 4 is seen an alternate mechanism by which to deliver coconuts from a silo or bin 54 to conveyor 11 for transport thereby to the processing station.

The base of the bin may feed to a delivery chute 55, which may be vibrated or shaken by a mechanism at 56, as will be known to those skilled in the art, to move coconuts to a delivery wheel 57 whose periphery may be segmented or pocketed to collect and carry individual coconuts, such as coconut 58, to conveyor 11.

In the particular embodiment of FIG. 5 is seen an alternate mechanism by which to section or portion coconuts fed onto conveyor 11. Two chains 59, 60 may be driven around sprockets to create a station there between to support or engage a coconut at the nip, at 61, where portioning or sectioning can be effected. The chains can be fitted with hooks, as before with respect to the wheels, to engage in the husks of the coconuts. By this means the two coconut sections which are created by the sectioning are separated in the zone 62 whereat can be mounted jets by which to remove the coconut WO 99/29188 PCT/AU98/01011 11 meat as before. The sprockets 63,64,65 may be fixed. The sprockets 66, 67 may be spring loaded to keep tension in the chain and to accommodate to coconuts of different sizes. The sprocket 68 may be driven by a chain 69 off a motor 70. The other chain can be run over a similar pattern of sprockets. The chains may be fitted with cup shaped elements which complement the shape of a coconut. The hooks may be mounted within these cups. The chains may be vertically tiered to feed a greater number of coconuts past the respective processing stations. In the zone 61 there may be three saws 71,72,73 in a three tier system, displaced as shown. In a three tier system there will may three removal prongs 74, 75, 76 oriented as shown.

In the particular embodiment of FIGS. 6 and 7 is seen in more detail a zone whereat coir can be released or removed from its woody shell. Coconut sections 78 produced by the above apparatus can be transported, face down, on a flat slatted conveyor 79, beneath an ideally spring loaded, trough conveyor 80, up to water jet 81. The action of the high pressure jet 81 can be operative to release or remove the coir from the woody shell, the water pressure moving the husk sideways and leaving the woody shell 83 free to continue on over flat conveyor 85, beneath spring loaded conveyor 84. The effect of the two spring loaded conveyors 80,84 is to hold the portions before and after the jet 81.

WO 99/29188 PCT/AU98/01011 12 In the particular embodiment of FIG. 8, coconut meat shells 86 are transported by a flat conveyor 87 to a planner or shaver 91 whereat the outer skin can be sliced off or otherwise removed. A trough conveyor 88 can bear down on the coconut meat shells, with its end roller 89 effective to flatten the coconut shell 90 prior to its meeting the planner 91. The shavings may be collected and fed to the copra dryer at 92. The shaved coconut meat 93 can be delivered to a drier to be desiccated.

The water jets at 23 in FIG. 1 may be the standard jets produced as cutting tools, typically powered off a high pressure plunger pump, as will be known to engineers skilled in the art.

Typically these can be operated at 2,000 psi, delivering 50 litres/min in a jet which is typically delivered from a 2.8 mm nozzle. It will be clear to those skilled in this art that there is a relationship between parameters such as pressure and flow rate and that these parameters may be varied considerably with equal effect in the cutting operation.

In operation in the present invention, the water jets may be operated continuously, effective to cut across the meat as the wheel carries a half coconut or portion past it. At a point towards the middle of the portion, water can be effective to blow the shell of meat out of its woody shell. Alternately, the water jets might be switched, to pulse a blast of water when the portion is properly positioned, but this complicates control of the apparatus.

WO 99/29188 PCT/AU98/01011 13 The divider which portions or halves the coconuts may be a circular saw, band saw, water jet, etc, ideally with a capacity to cut one to four coconuts per second.

The dryer which converts the meat to a final form may be a conventional fluidized bed dryer, or jet dryer, operating typically at 90-1200 C, with the temperature held below 120 0 C because at temperatures above that the oil usually exudes and is discoloured.

The invention may be equally applied to other nuts where a flesh or meat is to be released from a woody shell, with appropriate dimensional variation to suit the nut. The water jet technique might be used to husk nuts prior to their being portioned if this is desired.

The husked nuts might then be processed through a portioning device with their meat then removed. But a process such as this removes the husk which is a convenient means by which to mount the portions in the apparatus and some other mechanism needs to be used to engage with the woody shells to hold portions whilst the meat is removed.

Claims (19)

1. An apparatus for processing coconuts, said apparatus including:- spaced conveyor members each having a plurality of inwardly directed engagement members adapted in use to supportingly engage opposite sides s of a coconut located therein; a splitting station aligned with a travel path of said conveyor members, in use, to sever coconuts into portions as said coconuts are conveyed through said splitting station; a meat removal station having high pressure water jets oriented to direct high pressure water into an exposed interior region of severed coconut portions supported on respective said conveyor members to remove coconut meat from said severed portions; and, a disengagement station wherein severed coconut portions are disengaged from respective engagement members. 15

2. An apparatus as claimed in claim 1 wherein said conveyor members each describe circular paths whereby respective severed portions of a coconut follow divergent paths after said splitting station to expose respective interior regions of severed coconut portions.

3. An apparatus as claimed in claim 2 wherein said conveyor members are circular in plan and rotate in opposite directions about respective spaced .oaxes.

4. An apparatus as claimed in claim 1 wherein said conveyor members follow substantially parallel paths through said splitting station and thereafter diverge to expose respective interior regions of severed coconut portions. 25

5. An apparatus as claimed in any preceding claim wherein said O engagement members are adapted, in use, to mechanically engage an outer portion of a coconut on opposite sides thereof.

6. An apparatus as claimed in claim 5 wherein said engagement members are adapted to piece an outer husk of a coconut located between said conveyor members.

7. An apparatus as claimed in any preceding claim wherein said splitting Sstation includes a rotatable or reciprocatory saw blade.

8. An apparatus as claimed in any preceding claim wherein said high pressure water jets are adapted to deliver substantially continuous streams of water.

9. An apparatus as claimed in any one of claims 1 to 7 wherein said high pressure waterjets are each adapted to deliver a pulsed blast of water to an aligned coconut portion.

An apparatus as claimed in any preceding claim wherein said disengagement station includes ejectors which cause, in use, relative movement between said engagement members and respective severed portions secured thereto.

11. An apparatus as claimed in claim 10 wherein said ejectors are stationary members relative to which said conveyor members move.

12. An apparatus as claimed in any preceding claim including a metering device to meter coconuts into a region between said spaced conveyor 15 members.

13. An apparatus as claimed in any preceding claim including a skin removal station for removal of an outer skin on the coconut meat removed from the severed coconut portions.

14. An apparatus as claimed in claim 13 wherein said skin removal station includes a skin planing or shaving device.

15. A method of processing coconuts comprising the steps of:- supporting coconuts between spaced conveyor members having a :i plurality of inwardly directed engagement members to engage opposite sides of said coconuts; 0. a: 25 conveying said coconuts through a splitting station to sever said S. coconuts into portions; and, removing coconut meat from said severed portions whilst supported on respective conveyor members by directing a high pressure water jet into a central region of exposed coconut meat in said severed portions to dislodge said coconut meat from a respective coconut shell.

16. A method as claimed in claim 15 wherein the water jet is a substantially continuous stream of water. 16

17. A method as claimed in claim 15 wherein the water jet is a pulsed blast of water.

18. A method as claimed in claim 17 wherein the pulsed blast of water is delivered when said severed portion is aligned in a predetermined position relative to said water jet.

19. A method as claimed in any one of claims 15 to 18 wherein coconut meat removed from said severed portions is subjected to a mechanical skin removal process. A method as claimed in any one of claims 15 to 19 wherein the severed coconut portions, after removal of the coconut meat are processed to recover coconut shells and coconut fibre as separate products. C C C oo