US3663231A

US3663231A - Process of liquifying and conching refined chocolate and an apparatus for performing the process

Info

Publication number: US3663231A
Application number: US90298A
Authority: US
Inventors: Alfred George Tourell
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-11-17
Filing date: 1970-11-17
Publication date: 1972-05-16
Anticipated expiration: 1989-05-16

Abstract

Chocolate continuously fed from refiners is continuously liquified and conched in an apparatus consisting of a compression stage, a shredding stage, a vibration stage, a blending stage and a final conching stage arranged one after another. Each of the compression, shredding and vibration stages includes a rotary shaft extending in and along a trough and carrying blades appropriate to the function being performed. Each of the blending and final conching stages includes an upright cylindrical vessel containing a rotary gate-type blade rotatable about the axis of the vessel.

Description

[451 May 16, 1972 United States Patent Tourell ..99/244 X ......99/244 .........99/244 X ...99/236 CCX n l n ma mmmm mm m wa NLMHWHN 1334560 5555567 wwwwwww wwwwwmw 593242 530686 ,9 ,3 ,5 4003 56 6347 80 L 2222233 m P m a A m DL m NO S M AC G R m N O C w Y R T DSP m mum QIAH mE G], LE m RAG w F PN n OGP m m NAM AC SINR AO r C F m O R m ON v PCAP .m M w. k U

[22] Filed: 1970 Primary Examiner-Walter A. Scheel Assistant Examiner-Arthur 0. Henderson Att0rneyCushman, Darby & Cushman [21] Appl. No.:

Related US. Application Data ABSTRACT uously g ofa compresage, a blending ge arranged one after another.

Chocolate continuously fed from refiners is contin liquified and conched in an apparatus consistin [63] Continuation-in-part of Ser. No. 758,798, Sept. 10,

1968, abandoned.

52 [51] Int. [58] FieldofSearch....

edding and vibration stages includes a rotary shaft extending in and along a trough and carrying blades appropriate to the n ma mm d Hm ec .m m n m. bt S n 8 .U c n m References cued Each of the blending and final conchin upright cylindrical vessel containin UNITED STATES PATENTS g a rotary ga e-type blade rotatable about the axis of the vessel.

2,216,777 10/1940 Hollstein CC 2,355,539 8/1944 Lawton.................. 259/102 18 Claims,7Drawing Figures PATENTEI] MAY 1 6 I972 SHEET 3 OF 5 Li #4 F350 MOE PROCESS OF LIQUIFYING AND CONCHING REFINED CHOCOLATE AND AN APPARATUS FOR PERFORMING THE PROCESS CROSS REFERENCES TO RELATED APPLICATIONS This is a continuation-in-part of application Ser. No. 758,798 filed the the Sept. 1968, now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a process of liquifying and conching refined chocolate and an apparatus for performing the process.

2. Description of the Prior Art The conventional process of liquifying and conching refined chocolate is a batch process which occupies between 12 hours and 72 hours for complete processing of each batch, depending on the quality of chocolate to be produced. A batch of refined chocolate is carried on trolleys from the refiners and unloaded into a flat-bottomed trough of a liquifying and conching machine. A heavy roller of the machine is rolled toand-fro along the bottom of the trough. Either the roller is of granite and the trough bottom is of steel, or vice-versa. The liquid chocolate mass produced is removed from the trough and forwarded to blending vessels and then to storage vessels.

The liquifying and conching of refined chocolate become more difficult the lower the fat content of the chocolate. A chocolate of low fat content, i.e., less than 26 percent fat content, can be liquified and conched by the conventional process to give a good quality chocolate but the liquifying and conching take much longer than for a high fat content chocolate, assuming that the same quality chocolate is to be produced. The increasing cost of cocoa butter fat in recent years has led to a requirement for a process and apparatus capable of producing good quality chocolate relatively quickly from refined chocolate oflow fat content.

A process and a plant are known for the manufacture of chocolate from the necessary raw materials, such as sugar, milk and cocoa, in which the matter being processed is fed continuously through a number of stages. The raw materials are mixed in a coarse mixer and then fed to the first chamber of a series of short horizontal chambers each having a rotary horizontal shaft carrying rotary working members. The shafts are driven in unison by a common drive. The members of the first chamber co-operate with rough walls of the chamber to rub down the matter to a pasty mass.

The working members in the subsequent chambers of the series apply the mass to the walls of these chambers in a thin layer which has aroma-impairing substances and moisture removed therefrom by a device inducing a vacuum in these chambers. The desiccated mass may then be fed to refining rollers which reduce the mass to a crumb form. The crumb so produced is passed through a second series of chambers substantially identical to the first series. The pasty mass leaving the second series of chambers enters a conching zone consisting of two co-axial conical dishes of which one is rotated about the axis relatively to the other while this other is reciprocated along the axis. The mass enters the conching zone via an inlet arranged centrally of the dishes and leaves the conching zone at the periphery of the dishes. An ultrasonic vibrator situated centrally of the dishes may be used to constrict and enlarge alternately the inlet for the mass. This process and plant have the major disadvantage that a good quality chocolate cannot be produced if the refined chocolate is of low fat content. Chocolate of low fat content would not be liquified by the second series of chambers and would instead tend to clog the plant. The chocolate is not retained for long enough in the conching zone. The progress of the chocolate through the stages cannot be individually controlled for each stage. There is great risk of overheating of the chocolate during processing, because the rate of thermal dissipation would be insufficient. Moreover, the plant is very difficult to clean.

A conch machine is known comprising a horizontal trough containing two horizontal parallel rotary shafts carrying rotary blades and rotary spoon paddles. Mounted above the trough is a chamber containing two horizontal parallel rotary shafts carrying rotary radial discs of which the discs on one shaft interdigitate with the discs on the other shaft. Raw or unconched chocolate or cocoa is supplied to the trough and there beaten by the blades. The spoon paddles lift the chocolate or cocoa into a receptacle and onto the discs, where the chocolate or cocoa forms a thin layer which is subjected to aeration and which is continuously removed from the discs by means of scrapers which return it to the trough. When the mass has reached the desired character and degree of refinement, the trough is emptied by a screw conveyor. This machine has the disadvantage that it cannot produce a good quality chocolate from refined chocolate of low fat content. Low-fat chocolate would not be liquified efficiently by the machine but would tend rather to clog the discs, which would be particularly difficult to clean.

SUMMARY OF THE INVENTION It is an object of the invention to reduce the time taken for the liquifying and conching without necessarily lowering the quality of the chocolate produced, particularly in the case of chocolate of low fat content.

According to one aspect of the present invention, there is provided a process of liquifying and conching refined chocolate in which the chocolate continuously advances in liquifying and conching apparatus while being liquified and conched therein, the liquifying and conching of the refined chocolate comprising compressing the refined chocolate and thus both forming a stodgy mass of chocolate and forcing fat from the inside of the mass to the outside thereof, then shredding said stodgy mass and thus moving fat from the outside of the mass to the inside thereof to make the mass more fluid, and subsequently vibrating the more fluid mass and thus converting it into a pumpable liquid mass.

According to another aspect of the present invention, there is provided chocolate liquifying and conching apparatus, in which the chocolate being liquified and conched advances continuously, the apparatus comprising a compression stage in which refined chocolate is compressed into a stodgy chocolate mass and fat is forced from the inside of the mass to the outside thereof, a shredding stage which is downstream of said compression stage and continuously communicates therewith and in which the stodgy mass is shredded and thus fat is moved from the outside of the mass to the inside thereof to make the mass more fluid, and a vibration stage which is downstream of said shredding stage and continuously communicates therewith and in which the more fluid mass is vibrated and thus converted into a pumpable liquid mass, said compression stage comprising a trough, a rotary shaft extending in and along said trough, and blades mounted on said shaft at intervals therealong and compressing the refined chocolate in said trough, said shredding stage comprising a trough, a rotary shaft extending in and along its trough, and blades mounted on its shaft at intervals therealong, and said vibration stage comprising a trough, a rotary shaft extending in and along its trough, blades mounted on its shaft at intervals therealong, and substantially completely submerged in said more fluid mass, and drive means connected to its shaft for rotating its shaft at high speed.

Owing to the fact that the liquifying and conching of the invention is continuous and the mass passes through compression, shredding and vibration stages, it is possible to reduce the time taken for the liquifying and conching without lowering the quality of the chocolate produced. For example, it has been found possible to reduce the processing time from 12 hours to 1% hours for the lowest quality of chocolate produced.

BRIEF DESCRIPTION OF THE DRAWING FIG. 3,

FIG. 5 shows a plan view of respective troughs of a shredding stage and a vibration stage of the apparatus, but with not only covers removed but also an upper shaft of the vibration stage,

FIG. 6 shows a vertical section taken on the line VIVI of FIG. 5, and

FIG. 7 shows a plan view of a shaft with blades mounted thereon.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the apparatus shown, the chocolate being liquified and conched advances continuously. From refiners 30, refined chocolate is continuously fed by a continuous-type conveyor 31 to an inlet end of a horizontal trough 2 of a compression stage 1 of the apparatus. Mounted in the trough 2 and extending therealong is a horizontal rotary shaft 32 which is rotated by a motor 33 via reduction gearing 34. Fixed to the shaft 32 at the inlet end of the trough is a ribbon blade 35 which forwards the refined chocolate to an intermediate portion of the trough 2, in which portion gate-type blades 3 fixed to the shaft 32 at intervals therealong compress the refined chocolate and so force part of the fat content of the chocolate mass from the inside of the chocolate mass to the outside thereof. It will be understood that this fat content is basically cocoa butter but includes milk butter where milk chocolate is being produced. Partial baffles 36 and a full baffle 37 fixed in the trough at intervals therealong tend to restrict movement of the refined chocolate being compressed, and thus aid compression thereof. Under the action of the ribbon blade 35 and of the continuous supply of refined chocolate by the conveyor 31, the chocolate mass moves along the trough 2 to the outlet end thereof, where it falls over the baffle 37 and is aided by a gatetype blade 4 to fall continuously and directly into a horizontal trough 38 of a shredding stage 6 of the apparatus. The ribbon blade 35 is mounted on the shaft 32 by way of radial legs 35, and these legs and the radial legs 3 and 4' of the gate-

type blades

3 and 4 have externally threaded extensions, such as 101, which extend diametrically through the shaft and on the free ends of which are screwed nuts, such as 102, whereby the

blades

3, 4 and 35 are fastened to the shaft 32. Although the number and arrangement of blades on the shaft 32 is of course a matter of choice according to the intended conditions of operation, the shaft 32 as shown in FIGS. 3 and 4 has a single ribbon blade 35 followed by six gate-type blades 3 arranged two between each two baffles 36 and 37, and a single gatetype blade 4 after the baffle 37.

The chocolate leaves the stage 1 and enters the stage 6 as a stodgy mass or paste having at the inside thereof a large proportion of its hard sugar grains and at the outside thereof a large proportion of its fat content. Mounted in and extending along the trough 38 is a horizontal rotary shaft 39' which is rotated by a motor 18 via reduction gearing 19. Fixed to the shaft 39 at intervals therealong are blades 5. In operation, each blade 5 collects a ring of chocolate approximately coaxial with the shaft 39, these rings of chocolate rotating with the blades relatively to the remainder of the chocolate in the trough. The speed of flow of the chocolate mass along the trough 38 has in practice been found to be substantially independent of the form and raking of the blades 5, expect that the blades 5 should not be so greatly raked as to tend to forward the chocolate mass at a rate greater than the rate at which it tends to advance under the action of the continuous supply from the stage 1. Here again, the blades 5, which are of plate form, are mounted on the shaft 39 by way of radial legs 5' which have externally threaded extensions, such as 103, which extend diametrically through the shaft and on the free ends of which are nuts, such as 104, whereby the blades are fastened to the shaft. Although the number and arrangement of the blades on the shaft 39 is again a matter of choice, the shaft 39 as shown in FIG. 5 carries 1 3 blades 5.

To explain the action of the shredding stage 6, there will now be considered a particle of chocolate which has just dropped from the outlet of the stage 1. This particle advances, under the action of the continuous supply, towards the first blade 5 in company with a section of the mass of chocolate. As it reaches the ring of chocolate rotating with the first blade 5, it is shredded, by the ring of chocolate, from the section advancing therewith and then rotates with the ring of chocolate and the blade. While rotating, the particle advances towards another section of the mass of chocolate, this other section being between the first and second blades 5, and the first and second blades and their rings of chocolate rotating relatively to this other section. As the particle reaches this other section, it is shredded from the rotating ring of chocolate by this other section. The particle then advances with this other section and is ultimately shredded therefrom by the ring of chocolate rotating with the second blade. This action is then repeated again and again until the particle reaches the outlet end of the trough 38. Such action is of course undergone by the whole mass of chocolate and causes much of the fat content to move from the outside of the mass to the inside thereof to lubricate the hard sugar grains and thus make the mass more fluid. At the outlet end of the trough 38 is a cross-channel 40 through which the now more fluid mass flows continuously into a horizontal trough 41 of a vibration stage 7. Mounted in and extending along the trough 41 are two

horizontal rotary shafts

42 and 43 of which the shaft 43 is disposed above the shaft 42 at about the top surface level of the chocolate mass in the trough 41. An electric motor 44 rotates the shaft 42 via reduction gearing 20 and rotates the shaft 43 via the gearing 20 and further reduction gearing 20 A. The shaft 42 has fixed thereto at intervals therealong blades 8 and the shaft 43 has fixed thereto at intervals therealong blades 9. At the inlet end of the trough 41 is a full baffle 45 (removed in FIG. 6) over which the chocolate mass flows continuously from the cross-channel 40. Fixed at intervals along the trough 41 and at opposite sides thereof are partial baffles 46. At the outlet end of the trough 41 is another full baffle 47 tending to dam the chocolate mass. The blades 8, which are of plate form, are mounted on the shaft 42 by way of radial legs 8. The blades 9 are themselves in the form of legs of rectangular cross-section. The legs 8' and the blades 9 have externally threaded extensions, such as 105, which extend diametrically through the shaft and on the free ends of which are nuts, such as 106, whereby the blades are fixed to the shaft. Although their number and arrangement are naturally optional, there are 1 1 blades 8, arranged two or three between each two

baffies

45, 46 and 47, and six blades 9 arranged one or two between each two baffles. The shaft 42 is rotated at high speed and thereby the blades 8 slap those parts of the chocolate mass facing them and thus effectively gently vibrate those parts of the chocolate mass above the blades 8, whereby the hard sugar grains coat themselves completely with fat until, about mid-way along this trough, the mass is virtually liquid. At the end of the trough, the mass is in fact a pumpable liquid although the hard sugar grains nevertheless remain. The shaft 43 is rotated at low speed and the blades 9 serve to assist flow of the chocolate mass towards the outlet end of the trough 41 and also to break the top surface of the chocolate mass and thus prevent the fat layer, which tends to collect at the top of the chocolate mass, from becoming too concentrated. The pumpable liquid mass flows over the baffle 47 by way of a small channel formed by bending forwardly a comer 48 of the baffle and bending rearwardly a corner 49 of the baffle. The liquid mass flows continuously into an outlet pipe leading to a blending stage 12 including a vertical cylindrical vessel 14 in which is fitted a gate-type blade 50 rotatable about the vertical axis of the vessel 14. Here the pumpable liquid mass is not only additionally conched but is rapidly blended with additives, for example additional cocoa butter, lecithin and flavorings, supplied to the blending stage via an additive inlet 22 of the vessel 14. Since the blending and additional conching action tends to drive the mass in the blending stage to the top of the vessel 14, the inlet 51 for the pumpable liquid mass is at the bottom of the vessel and the outlet 52 for the blended mass is at the top of the vessel. The outlet 52 is connected continuously via a pipe to a final conching stage 23 consisting of a vessel 16 substantially identical to the vessel 14 and a gate-type blade 17 identical to the blade 50. correspondingly, the inlet 53 for the blended mass is at the bottom of the vessel 16, and the outlet 54 for the finally conched mass is at the top of the vessel 16. The gate-type blades 50 and 17 are rotated about the vertical axes by electric motors 55 via reduction gearing 21.

To permit heating or cooling selectively the chocolate in the troughs and vessels, substantially all of the wall portions of the troughs and vessels which normally come into contact with the chocolate mass are jacketed. For example, jacketing is indicated at 56 for the trough 2, the interior of the jacketing being supplied with coolant or heating liquid through an inlet pipe 57, the coolant or heating liquid leaving the jacketing 56 by way of an outlet pipe 58. During initial starting-up of the apparatus, and during normal stoppages, the heating liquid is passed through the jacketing to prevent solidification of the chocolate mass. During normal operation of the apparatus, part of the work performed by the motor 33 is converted into thermal energy which tends to increase the temperature of the chocolate mass. To prevent this temperature from becoming greater than desired, coolant is passed through the jacketing 56 during normal operation of the apparatus. Similarly and for the same purposes, the

troughs

38 and 41 and the

vessels

14 and 16 are correspondingly jacketed, such jacketing being shown at 59 for the trough 41 and at 60 and 61 for the vessels l4 and 16.

It may happen, during stoppage of the apparatus, that the beginning of the outlet pipe 10 becomes clogged with solidifying chocolate. For the purpose of destroying such a blockage, a vibrator (not shown) is fitted at the beginning of that outlet pipe 10 and is temporarily operated when the apparatus is restarted.

For lower qualities of chocolate, the conching can be accelerated by providing a small recycling pump 62 at the beginning of the outlet pipe 10 to return the pumpable liquid mass to the inlet end of the trough 2.

For prolonged stoppages of the apparatus, for example stoppages of two or three weeks, the chocolate is completely emptied from the apparatus. For this purpose, the

stages

6, 12 and 23 are automatically self-emptying, whereas the stages 1 and 7 can be self-emptied manually. Thus, each of the

full baffles

37 and 47 is formed at its lowermost region with a circular hole normally closed by a circular sluice plate. Since the sluice plates and their control arrangements at the two baffles are identical, only the sluice plate and its control arrangement at the baffle 37 will be described. As shown in FIG. 2, the baffle 37 is formed at its lowermost region with a circular hole 63 which is closable by a circular sluice plate 64 turnable about a horizontal pin 65. The plate 64 carries a running nut which cooperates with a screw 66. The screw 66 is so mounted in a cover 67 of the trough 2 as to be rotatable but not axially displaceable. The screw 66 has fixed thereto at its upper end a handle 68 whereby it may be manually rotated to turn the plate 64 to open and close the hole 63. It will be understood that the

troughs

38 and 41 have covers corresponding to the cover 67 of the trough 2, but that these have been omitted from FIG. 1 for ease of illustration.

FIG. 7 shows blades a fixed to a shaft b. The blades a of this Figure represent the blades 5 or the blades 8, the shaft b representing therefore the shaft 39 or the shaft 42. In FIG. 7, the blades a are viewed radially, so that only their radially outer ends are seen. The longitudinal center line of each blade a extending from the radially outer end thereof to the radially inner end thereof is a radius of the shaft b and is therefore contained in an axial plane 0 of the shaft b. Each blade a is raked at an angle a to the associated plane 0, and it can be seen that two blades a in FIG. 7 are oppositely raked. If the chocolate were to be flowing from right to left in FIG. 7, and the shaft b were to be rotating in the sense of the arrow d, then the lefthand blade a would have its leading edge e behind its lagging edge f in the direction of flow of the chocolate mass, whereas the right-hand blade a would have its leading edge e ahead of its lagging edge f in the direction of flow of the chocolate mass. If desired, some of the blades 5 can be raked as the lefthand blade a, and the others of the blades 5 raked as the righthand blade a, or all of the blades 5 may be raked as the lefthand blade a, or all raked as the right-hand blade a. The angle a between each blade 5 and the plane 0 is between 0 and 30 and, in fact, should not exceed 30 for a blade 5 raked as the left hand blade a, since otherwise the blade will forward the chocolate mass along the trough 38 too quickly for the shredding to be correctly performed. As regards the blades 8, these are raked at an angle a of between 0 and l0 and, preferably, some of the blades 8 are raked as the left-hand blade a and the others are raked as the right-hand blade :2. in order to increase the gentle vibration effect of the stage 7.

The blades 9 are of bar form and are slightly inclined to axial planes of the shaft 43 such that their lagging edges are disposed ahead of their leading edges in the direction of movement ofthe chocolate mass along the trough 41. Alternatively, some of the blades 9 could be raked in the opposite sense.

The apparatus described has the advantage of preventing much of the loss of valuable cocoa butter which occurs with the conventional apparatus, the apparatus described achieving this by keeping the chocolate mass more confined and by shortening the time cycle required for conching.

The apparatus described can be completely enclosed and have guarded viewing apertures and, in fact, once the process has fully commenced, that is to say the apparatus has completely filled, no operator is normally required.

An example is given of a 5,000 lbs. per hour apparatus wherein the time cycle has been found to be as follows. It required approximately 6,500 lbs. of chocolate initially to fill the three stages 1, 6 and 7 of the apparatus and this took approximately IV; hours to perform, and from then on the flow of refined chocolate in the form of milk chocolate crumb from the refiners was set to 5,000 lbs. per hour, the apparatus then maintaining a constant output of approximately 5,000 lbs. per hour. This apparatus measured overall 17 ft. 6 in. long by l 1 ft. 6 in. wide by l 1 ft. 6 in. high and weighed approximately 16 tons. Each trough was 10 ft. long and 2 ft. wide, the trough 2 being 3 ft. deep, the trough 38 being 3 ft. 6 in. deep and the trough 41 being 4 ft. deep. The blades on each shaft were angularly spaced apart around the shaft at intervals of between and The

blades

3, 5, 8 and 35 had a working clearance of 3/16 in. from the curved walls of their troughs, while the

blades

3, 5 and 8 were arranged at centers of between 9 in. and 12 in. along their shaft. The

baffles

36, 37, 45, 46 and 47 were in the form of vertical plates mounted at intervals of between 1 ft. 6 in. and 3 ft. along their trough. The speeds of rotation of the

shafts

32, 39, 42 and 43 were 30, 60, and 45 R.P.M., respectively, and the power output of each reduction gearing 34, 19 and 20 was 40 I-I.P. Milk chocolate crumb containing 24 percent cocoa butter and milk fats entered the stage 1, which had a capacity of 1,400 lb., at a temperature of 90 F, remained in the stage for 20 mins. and left at a temperature of 120 F. It entered the stage 6, which had a capacity of 1,600 lb., at a temperature of 120 F, remained in the stage for 30 mins. and left at a temperature of 120 F. While in the stage 6, it had 2 percent cocoa butter fat added, because the pump 62 was not in use. It entered the stage 7, which had a capacity of 3,200 lb., at a temperature of 120 F, remained there for 30 mins. and left at a temperature of 120 F. In the

stages

12 and 16, the temperature remained at about 120 F, their motors 55 being of 30 and 20 l-l.P., respectively. The chocolate remained in each of these two stages for about 8 mins. each, each stage having a capacity of 700 lb. The materials blended with the chocolate in the stage 12 were 4 percent cocoa butter fat and 0.2 percent lecithin.

What is claimed is:

1. Chocolate liquifying and conching apparatus, in which the chocolate being liquified and conched advances continuously, the apparatus comprising a compression stage in which refined chocolate is compressed into a stodgy chocolate mass and fat is forced from the inside of the mass to the outside thereof, a shredding stage which is downstream of said compression stage and continuously communicates therewith and in which the stodgy mass is shredded and thus fat is moved from the outside of the mass to the inside thereof to make the mass more fluid,-and a vibration stage which is downstream of said shredding stage and continuously communicates therewith and in which the more fluid mass is vibrated and thus converted into a pumpable liquid mass, said compression stage comprising a trough, a rotary shaft extending in and along said trough, and blades mounted on said shaft at intervals therealong and compressing the refined chocolate in said trough, said shredding stage comprising a trough, a rotary shaft extending in and along its trough, and blades mounted on its shaft at intervals therealong, and said vibration stage comprising a trough, a rotary shaft extending in and along its trough, blades mounted on its shaft at intervals therealong and substantially completely submerged in said more fluid mass, and drive means connected to its shaft for rotating its shaft at high speed.

2. Apparatus according to claim 1, and further comprising a blending stage which is downstream of said vibration stage and continuously communicates therewith and in which said pumpable liquid mass is blended with additives while being further conched.

3. Apparatus according to claim 2, and further comprising a final conching stage which is downstream of said blending stage and continuously communicates therewith.

4. Apparatus according to claim 3, wherein said final conching stage comprises a vessel, an inlet of said vessel for the blended mass, an outlet of said vessel for the finally conched mass, and a rotary gate-type blade mounted in said vessel for performing the final conching.

5. Apparatus according to claim 4, wherein said gate-type blade is mounted for rotation about a substantially vertical axis, and said inlet is at a lower level than said outlet.

6. Apparatus according to claim 2, wherein said blending stage comprises a vessel, a first inlet of said vessel for said pumpable liquid mass, a second inlet of said vessel for said additives, and an outlet of said vessel for the blended mass, and a rotary gate-type blade mounted in said vessel for performing the blending.

7. Apparatus according to claim 6, wherein said gate-type blade is mounted for rotation about a substantially vertical axis, and said first inlet is at a lower level than said outlet.

8. Apparatus according to claim 1, wherein said blades of said compression stage are gate-type blades.

9. Apparatus according to claim 1, wherein said compression stage further comprises baffle means in its trough tending to restrict movement of the refined chocolate being compressed.

10. Apparatus according to claim 9, wherein said baffle means comprises sluice means openable to allow complete emptying of the trough of said compression stage.

1 1. Apparatus according to claim 1, wherein said blades of said shredding stage are slightly inclined to axial planes of its shaft, the leading edges of these blades being offset relatively to the respective lagging edges of these blades in the direction of movement of the stodgy mass along the shaft.

12. Apparatus according to claim 11, wherein said blades of said shredding stage are inclined at between 0 and 30 to said axial planes.

13. Apparatus according to claim 1, wherein said blades of said vibration stage are slightly inclined to axial planes of its shaft, and some of these blades along this shaft have their leading edges disposed ahead of their respective lagging edges in the direction of movement of the more fluid mass along the shaft, and the others of these blades have their leading edges disposed rearwardly of their respective lagging edges in this direction of movement.

14. Apparatus according to claim 13, wherein said blades of said vibration stage are inclined at between 0 and 10 to said axial planes of its shaft.

15. Apparatus according to claim 1, wherein said vibration stage further comprises another rotary shaft extending in and along its trough and above its first-mentioned shaft, and other blades mounted on said other rotary shaft and slightly inclined to axial planes of said other rotary shaft such that their lagging edges are offset with respect to their respective leading edges in the direction of movement of the more fluid mass along said other rotary shaft.

16. Apparatus according to claim 1, wherein said vibration stage further comprises baffle means in its trough tending to dam the pumpable liquid mass.

17. Apparatus according to claim 16, wherein said baffle means comprises sluice means openable to allow complete emptying of said trough of said vibration stage.

18. Apparatus according to claim 1, and further comprising recycling means for recycling at least part of said pumpable liquid mass to said refined chocolate.

Claims

1. Chocolate liquifying and conching apparatus, in which the chocolate being liquified and conched advances continuously, the apparatus comprising a compression stage in which refined chocolate is compressed into a stodgy chocolate mass and fat is forced from the inside of the mass to the outside thereof, a shredding stage which is downstream of said compression stage and continuously communicates therewith and in which the stodgy mass is shredded and thus fat is moved from the outside of the mass to the inside thereof to make the mass more fluid, and a vibration stage which is downstream of said shredding stage and continuously communicates therewith and in which the more fluid mass is vibrated and thus converted into a pumpable liquid mass, said compression stage comprising a trough, a rotary shaft extending in and along said trough, and blades mounted on said shaft at intervals therealong and compressing the refined chocolate in said trough, said shredding stage comprising a trough, a rotary shaft extending in and along its trough, and blades mounted on its shaft at intervals therealong, and said vibration stage comprising a trough, a rotary shaft extending in and along its trough, blades mounted on its shaft at intervals therealong and substantially completely submerged in said more fluid mass, and drive means connected to its shaft for rotating its shaft at high speed.

11. Apparatus according to claim 1, wherein said blades of said shredding stage are slightly inclined to axial planes of its shaft, the leading edges of these blades being offset relatively to the respective lagging edges of these blades in the direction of movement of the stodgy mass along the shaft.

12. Apparatus according to claim 11, wherein said blades of said shredding stage are inclined at between 0* and 30* to said axial planes.

14. Apparatus according to claim 13, wherein said blades of said vibration stage are inclined at between 0* and 10* to said axial planes of its shaft.