METHOD OF AND PRESS FOR SEPARATING COCOA MASS INTO COCOA BUTTER AND COCOA CAKE

Abstract

The invention relates to a method of separating cocoa mass into cocoa butter and cocoa cake by means of a press (1) comprising one or more pressing elements (6) in turn comprising a pot (7) having a cavity (8) for receiving cocoa mass to be pressed, a squeezer (9) located at least partially in the cavity (8), and at least one filter (11) disposed in front of the squeezer (9) and/or on the side of the cavity (8) opposite the squeezer (9), which method comprises the steps of filling the cavity or cavities (8) with cocoa mass, exerting pressure on the pressing element(s) (6) thus pressing cocoa butter through the filter(s) (11), releasing pressure from the pressing element(s) (6), and opening the pot(s) (7) to remove the cocoa cake(s) from the cavity or cavities (8). Prior to releasing the pressure from the pressing element(s) (6), cocoa butter is purged from at least the space(s) (13) behind the filter(s) (11).

Claims

1. A method of separating cacao mass or products comparable to cacao mass into liquid fat and cake, by means of a press comprising one or more pressing elements, each said pressing element, in turn comprising a pot having a cavity for receiving mass to be pressed, a squeezer located at least partially in the cavity, and at least one filter disposed in front of the squeezer and/or on a side of the cavity opposite the squeezer, which method comprises steps of filling the one or more cavities with mass, exerting pressure on the one or more pressing elements thus pressing liquid fat through the one or more filters, releasing pressure from the one or more pressing elements, and opening the one or more pots to remove one or more cakes from the one or more cavities, characterised in that, prior to the step of releasing the pressure from the one or more pressing elements, liquid fat is purged from at least one or more spaces space(s) behind the one or more filters.

2. The method according to claim 1, wherein, prior to the step of releasing the pressure from the one or more pressing elements, liquid fat is purged from the one or more filters.

3. The method according claim 1, wherein the liquid fat is purged by means of a flowable medium.

4. The method according to claim 3, wherein, during said purging, a pressurized medium is fed to the one or more spaces behind the one or more filters and/or the pressurized medium and the liquid fat are withdrawn from said one or more spaces.

5. The method according to claim 4, wherein a flow of the pressurized medium is generated in the one or more spaces behind the one or more filters.

6. The method according to claim 5, wherein the flow of the pressurized medium is generated with a pressure difference between an inlet and an outlet of at least 0.2 bar.

7. A press for separating cacao mass or products comparable to cacao mass into liquid fat and cake, said press comprising a frame, one or more pressing elements disposed in the frame, and means for exerting pressure on the one or more pressing elements, wherein each of the one or more pressing elements comprises a pot having a cavity for receiving mass to be pressed, a squeezer located at least partially in the cavity, at least one filter disposed in front of the squeezer and/or on a side of the cavity opposite the squeezer, and an outlet for liquid fat, characterised in that at least one of the one or more pressing elements is provided with an inlet for a flowable medium for purging liquid fat from at least one of one or more spaces behind the one or more filters.

8. The press according to claim 7, wherein said one or more inlets are connected to a source of the medium, which source comprises a pump and/or is at an elevated pressure.

9. The press according to claim 7, wherein said one or more outlets for liquid fat are connected to a low pressure source.

10. The press according to claim 7, wherein the one or more inlets for a medium for purging liquid fat are provided in the one or more squeezers.

11. The press according to claim 7, wherein the one or more inlets and the one or more outlets are positioned substantially diametrically.

12. The press according to claim 7, wherein at least one of the one or more squeezers comprises at least one channel for collecting liquid fat pressed through the respective one or more filters.

13. The press according to claim 7, further comprising means configured for operating the press to perform the method of claim 1.

14. The press according to claim 7, wherein the one or more cavities are cylindrical, said one or more filters are flat or substantially flat and/or wherein the side of the one or more cavities opposite said one or more squeezers is formed by a back of an adjoining one of said one or more squeezers.

15. The press according to claim 7, wherein in at least one of the one or more pressing elements, said one or more filters are disposed in front of the one or more squeezers and on the side of the one or more cavities opposite the one or more squeezers and when the press is in a filling position, a distance between the one or more filters is smaller than 85 mm.

16. The method according to claim 5, wherein the flow of the pressurized medium is generated with a pressure difference between an inlet and an outlet of at least 0.4 bar.

17. The press according to claim 7, wherein all of the one or more pressing elements are provided with an inlet for a flowable medium for purging liquid fat from all of the one or more spaces behind the one or more filters.

18. The press according to claim 9, wherein the low pressure source is a vacuum pump.

19. The press according to claim 15, wherein the distance between the one or more filters is small than 60 mm and larger than 30 mm.

20. The press according to claim 7, wherein said one or more inlets are connected to a source of the medium, which source comprises a pump and/or is at an elevated pressure, said one or more outlets for liquid fat are connected to a vacuum pump, the one or more inlets for a medium for purging liquid fat are provided in the one or more squeezers, the one or more inlets and the one or more outlets are positioned substantially diametrically, at least one of the one or more squeezers comprises at least one channel for collecting liquid fat pressed through the respective one or more filters, the one or more cavities are cylindrical, said one or more filters are flat or substantially flat and/or wherein the side of the one or more cavities opposite said one or more squeezers is formed by a back of an adjoining one of said one or more squeezers, said press further comprising means configured for operating the press to perform the method of claim 1, and in the one or more pressing elements, said one or more filters are disposed in front of the one or more squeezers and on the side of the one or more cavities opposite the one or more squeezers and when the press is in a filling position, a distance between the one or more filters is smaller than 60 mm and larger than 30 mm.

Description

[0024] The invention will now be explained in more detail with reference to the drawings, which show an example of a hydraulic cocoa press according to the invention.

[0025] FIG. 1 is a perspective view of a hydraulic cocoa press according to the invention.

[0026] FIG. 2 is a front view of a pressing element of the press according to FIG. 1.

[0027] FIG. 3A is a cross-sectional view of a pressing element of the press of FIG. 1, in the filling position.

[0028] FIG. 3B is a cross-sectional view of a gas/liquid separator and pump connected to the outlets of the pressing elements of the press of FIG. 1.

[0029] FIGS. 4A and 4B are enlargements of parts of FIG. 3A showing the inlet and outlet of the pressing element.

[0030] FIGS. 5A to 5D are various views of a filter and filter plate used in the press according to FIG. 1.

[0031] FIG. 1 shows a hydraulic cocoa press 1 comprising a frame 2 and a hydraulic cylinder 3, two tie rods 4, and a retainer 5 mounted in the frame 2. A number of pressing elements 6, e.g. sixteen, eighteen or twenty, is located between the cylinder 3 and the retainer 5.

[0032] Each of the pressing elements 6, shown in more detail in FIGS. 2 and 3A, comprises a pot 7 having a cylindrical cavity 8 for receiving cocoa mass to be pressed, and a squeezer 9, also known as counter pot or male pot, sealingly positioned in the cavity 8. The pots 7 as well as the squeezers 9 are slidingly mounted round the tie rods 4 by means of circular openings 10, which are formed in the side portions of the pots 7 and the squeezers 9.

[0033] The cavity 8 is limited on both sides (in axial direction) by a disc-shaped filter 11, e.g. a filter cloth or metal mesh known in itself, mounted on a filter plate 12, as shown in FIG. 5A.

[0034] The front side of the filter plate 12, i.e. the side facing the cavity 8 of a pot 7, comprises at least one groove 13, in this example in the shape of a spiral (FIGS. 5C and 5D), for collecting cocoa butter pressed through the filter 11. The back side of the filter plate 12 (FIG. 5B) comprises at least one channel 14, in this example a plurality of concentric channels interconnected by a plurality of radial channels, for guiding the cocoa butter to an outlet of the pressing element 6, which at least one channel 14 is connected to the channel 13 on the front side of the filter plate 12 by means of a plurality of bores 15 extending through the plate 12.

[0035] One filter plate is attached to the squeezer, whereas the other filter plate is attached to the back of a squeezer which forms part of an adjoining pressing element.

[0036] The pots include inlets (not shown; known per se) for the cocoa mass, whilst the squeezers 9 include outlets 16, shown enlarged in FIG. 4B, for discharging cocoa butter that has been pressed through the filters 11. In accordance with the present invention, all of the squeezers 9 are in addition provided with an inlet 17, shown enlarged in FIG. 4A, for a medium for purging cocoa butter from at least the space behind the filters, typically at least from the channel(s) on the front side of the plate. This inlet may, e.g., be comprised of a vent or be connected to a source of the purge medium, which source comprises a pump and/or is at an elevated pressure.

[0037] The outlets 16 of the squeezers 9 are connected, via a three-way valve 18 and a gas/liguid separator 19 for separating the purge gas from the cocoa butter, to a vacuum source, in this example a vacuum pump 20.

[0038] FIGS. 1 and 3A show the press 1 in the filling position. In this position, the plunger of the hydraulic cylinder 3 occupies (in FIG. 1) its extreme left-hand position, and the spacing between the disc-shaped filters 11, and thus the volume of cavity 8 in each of the pressing elements 6, is at its maximum. In this example, the spacing between the filters 11 that are present in each of the pressing elements 6 is 65 mm in the filling position.

[0039] During operation, the cavities of the cocoa press are filled with cocoa mass and, once filled, the pressing elements are compressed evenly by moving the plunger of the hydraulic cylinder towards the retainer until the pressure reaches a specific threshold value, e.g. 500 bar. When a sufficient amount of butter has been pressed from the cocoa mass, the cocoa butter in the channel(s) on the front side of the filter plates and downstream from the filters is purged. In this example, purging is achieved by means of the vacuum pump and the vents that allow air to enter the squeezers and flush out the butter. When all or most of the butter has been purged from behind the filterthus hydraulically separating the butter from the resiliently compressed cocoa cakesand optionally from the filters and filter plates, i.e. from the bores in and from the channel(s) on the back of the filter plate, the pressure is released and the press is returned to its starting position. At that position, the pots are pushed (or pulled) over the squeezers, and the cocoa cakes fall out. Finally, the pots are returned to the starting position and the cycle is complete.

[0040] In several experiments, the cakes contained, if the butter was purged from behind the filters before releasing pressure, approximately 5-10% less fat when compared to cakes obtained with cycles wherein no butter was purged.

[0041] From the foregoing, it will be apparent that the invention offers significant advantages over prior art presses whilst the measures to be taken can be relatively simple. Existing presses can be made suitable for the present invention by providing at least one, preferably all of the pressing elements with an inlet for a medium for purging cocoa butter from at least the space behind the at least one filter or exchanging at least one, preferably all of the pressing elements with a pressing element comprising such an inlet.

[0042] The invention is not limited to the embodiment as described above, which can be varied in several ways within the scope of the claims, of course. Thus, the press can also be used for products of which the pressing and filtration behaviour is comparable to that of cocoa mass.