Extruder for Feed- and Foodstuffs

Abstract

An extruder for making meat analogue products, where the extruder comprises a product outlet (22), and a longitudinal barrel (8) comprising an inner surface (14) and an outer surface, and where the extruder further comprises heating means for heating at least a part of said inner surface, where said barrel (8) interconnects with said product inlet (5) and outlet (22), where the extruder further comprises a rotor (16) arranged coaxially inside said barrel (8), where said rotor (16) comprises drive means (19) for rotating said rotor (16) in relation to the barrel (8).

Claims

1. Extruder for making meat analogue products, where the extruder comprises a product inlet and a product outlet, and a longitudinal barrel comprising an inner surface and an outer surface, and where the extruder further comprises heating means for heating at least a part of said inner surface, where said barrel interconnects with said product inlet and outlet and defines an interior space, where the extruder further comprises a rotor arranged coaxially inside the interior space of said barrel, where said rotor has a first end and a second end, a length, a radial thickness and an outer surface and an inner surface, where said rotor further comprises drive means for rotating said rotor in relation to the barrel wherein said extruder further comprises a coaxial centre core, having a cylindrical cross section, and extending at least partly in the longitudinal direction of the barrel, where the centre core comprises an outer surface, where said rotor is arranged rotatably in relation to the inner surface of the barrel and in relation to the outer surface of the centre core, where the rotor comprises drive means for direct or indirect transfer of a rotational torque at both ends of said rotor.

2. Extruder according to claim 1, wherein both of the coaxial inner surface of the barrel and the outer surface of the centre core is arranged with a distance to the surfaces of the rotor, where the mentioned distance is between 0 and 3 millimetres, preferably between 0.2 and 1.5 millimetres, and where the distance between the inner surface of the barrel and the outer surface of the centre core is between 2 and 12 millimetres, and preferably between 5 and 7 millimetres, where the extruder further comprises an axial outlet.

3. Extruder according to claim 2, wherein said axial outlet has a ring shaped appearance corresponding to the ring shaped cross sectional area between the barrel and the centre core.

4. Extruder according to claim 1, wherein the centre core comprises heating means for heating at least the outer surface of said centre core.

5. Extruder according to claim 1, wherein the extruder comprises means for rotating said centre core about its longitudinal axis and in relation to said longitudinal barrel.

6. Extruder according to claim 1, wherein the rotor comprises scraping means constituted by at least one vane of the rotor, where the at least one vane of the rotor extends between the first end and the second end of the rotor and along the outer surface of the centre core and along the inner surface of the barrel.

7. Extruder according to claim 1 wherein the rotor comprises a central through-going shaft, where the through-going shaft is rigidly and at least indirectly connected to vanes of said rotor.

8. Extruder according to claim 1, wherein the rotor comprises drive means for rotating said rotor, where the rotor comprises two sets of drive means, a first set at or near one end of the rotor, and a second set at or near a second end of the rotor.

9. Extruder according to claim 1, wherein the rotor comprises a first end part and a second end part and at least one vane extending between said first and second end parts, where at least one of said end parts are releasably connected to the at least one vane, and further comprises mechanical engagement means for connecting said at least one vane to said at least one end part.

10. Extruder according to claim 1, wherein at least the barrel is connected to a mixing housing, and further comprises means for supply of e.g. steam, water and oil into the interior space of the extruder.

11. Extruder according to claim 1, wherein at least the rotor comprises a non-stick coating on at least a part of the rotor.

12. Extruder according to claim 1, wherein a number of extruders are placed next to each other in a block of extruders.

13. Extruder according to claim 1, wherein the extruder further comprises a pre-heating and mixing tank prior to the inlet and a mixing housing.

14. Extruder according to claim 1, wherein the extruder further comprises at least one of the following features arranged after the product outlet: a by-pass, a counter pressure valve, a grilling unit, a cooling unit, a cutting unit.

15. Method for making meat analogue products from an emulsion, where the method comprises operating an extruder according to claim 1 wherein the emulsion is forwarded axially through the extruder in relation to the inner surface of the barrel and in relation to the outer surface of the centre core while also being moved in a tangential direction in relation to said surfaces and heated and thus transformed from an emulsion into a firm product.

16. Method for making meat analogue products from an emulsion according to claim 15, wherein the emulsion is forwarded in the extruder with an adjusted speed allowing the emulsion to build up a specific surface structure/texture at the surfaces of the product sliding against the heated inner surfaces of the barrel and of the centre core.

17. Use of an extruder for making meat analogue products according to claim 1, wherein the extruder is used for producing e.g. pizza toppings and kebab products, where the product has a firm structure and texture, where the outermost layers of the product has a first structure and texture, and where at least one centre layer has a different structure and texture.

18. Use of an extruder for making meat analogue products according to claim 17, wherein the meat analogue product comprises proteins mainly from meat.

19. Use of an extruder for making meat analogue products according to claim 17, wherein the meat analogue product comprises proteins mainly from vegetables.

20. Use of an extruder for making meat analogue products according to claim 17, wherein the meat analogue product comprises mainly carbohydrates.

Description

DESCRIPTION OF THE DRAWING

[0106] The invention will be described in further detail below by means of non-limiting embodiments with reference to the drawing, in which:

[0107] FIG. 1 shows an example of an extruder having further equipment installed in front of and after the extruder.

[0108] FIG. 2 shows a cross section of an extruder barrel and a centre core with a rotor.

[0109] FIG. 3 shows a centre core and a rotor.

[0110] FIG. 4 shows an example of a centre core with a rotor having helical shaped scraping means.

[0111] FIG. 5 shows an extruder with several sections along the barrel and with a dual drive system at the rotor.

[0112] FIG. 6 shows a rotor with a central through-going shaft for transferring torque.

[0113] FIG. 7 shows a layered meat analogue product.

[0114] FIG. 8 shows a rotor unit comprising a centre core with rotor and two sets of drive means.

[0115] FIG. 9 shows the same rotor unit as seen in FIG. 8, but from a different angle.

[0116] FIG. 10 shows the first end of the rotor unit of FIGS. 8 and 9.

[0117] FIG. 11 shows the second end of the rotor unit of FIGS. 8 and 9.

[0118] FIG. 12 shows cut out details in the first end of a rotor unit.

[0119] FIG. 13 shows cut out details in the second end of a rotor unit.

[0120] In the drawing, the following reference numerals have been used for the designations used in the detailed part of the description:

LIST OF POSITION NUMBERS

[0121] 1 Extruder

[0122] 2 Pre-bin

[0123] 3 Pre-heating/mixing tank

[0124] 4 Stirrer

[0125] 5 Product inlet

[0126] 6 Inlet section

[0127] 7 Pump

[0128] 8 Barrel

[0129] 9 First barrel section

[0130] 10 Second barrel section

[0131] 11 Third barrel section

[0132] 12 Inlets in mixing housing

[0133] 13 Inlets in barrel

[0134] 14 Inner surface in barrel

[0135] 15 Centre core

[0136] 16 Rotor

[0137] 17 Scraping means

[0138] 18 Flights/vanes

[0139] 19 Drive means

[0140] 20 Energy/steam connection to the centre core

[0141] 21 Sensor

[0142] 22 Product outlet

[0143] 23 By-pass valve

[0144] 24 Grilling section

[0145] 25 Cooling section

[0146] 26 Cutting section

[0147] 27 Direction arrow

[0148] 28 Outer surface of centre core

[0149] 29 Ring shaped space in the extruder

[0150] 30 Scraping blade/vane/flight

[0151] 31 Scraping edge

[0152] 32 Stiffener between rotor blades/vanes/flights

[0153] 33 Dual drive system

[0154] 34 Through-going shaft

[0155] 35 Meat analogue product

[0156] 36 Outer layer

[0157] 37 Centre layer

[0158] 38 Rotor unit

[0159] 39 Electric motor

[0160] 40 First set of chain drive

[0161] 41 Second set of chain drive

[0162] 42 First rotor end part

[0163] 43 Second rotor end part

[0164] 44 Mounting flange

[0165] 45 Catch means

[0166] 46 Cut out in vane

DETAILED DESCRIPTION OF THE INVENTION

[0167] FIG. 1 shows an example of an extruder 1 having further equipment installed in front of and after the extruder 1. In front of the extruder 1, a pre-bin 2 is seen where the emulsion/product is stored and from where the product is led to a pre-heating and/or mixing tank 3. Inside the pre-heating/mixing tank 3, a stirrer 4 is seen which stirs the added product and ingredients into a homogeneous emulsion or product. The product is led further into an inlet 5 in the extruder 1 via the inlet section 6. On the inlet line a pump 7 is provided for pumping the product through the extruder 1. The inlet section 6 is connected to the barrel 8 of the extruder 1. The barrel 8 is divided into three sections 9, 10, 11 where different conditions may be present in each section 9, 10, 11.

[0168] Each section 9, 10, 11, or the barrel 8 in general, may comprise one or more sensors for detection of temperature, pressure or other process parameters that could be attractive to detect.

[0169] The inlet section 6 has inlets 12 for e.g. steam, water and oil which are led into the inlet section 6 and into the product inside the interior of the extruder 1. The barrel 8 also has inlets 13 for indirect supply of e.g. steam in order to heat up the inner surface 14 of the barrel 8.

[0170] Centrally in the barrel 8, a centre core 15 is seen depicted with a rotor 16 arranged around a stationary centre core 15, where the rotor 16 comprises scraping means 17, in the shape of a helical screw conveyor, with flights/vanes 18. The rotor 16 is rotated by means of the drive means 19 arranged at the end of the mixing housing 6. The centre core 15 is energised with e.g. steam via a connection 20.

[0171] Further down the line of the apparatus seen in FIG. 1, there is arranged a sensor 21 e.g. a temperature and/or pressure sensor at the product outlet 22 and a by-pass valve 23 that allows for a product to be bypassed until e.g. a specific temperature is measured at the sensor 21. Even further down the line, a grilling section 24 is arranged and can be used to apply a desired grill effect on the product before cooling it in a cooling section 25. The product can be led through the grilling section 24 and the cooling section 25 with or without any process taking place and into a cutting section 26, where the product can be cut into pieces of a desired size.

[0172] FIG. 2 shows a cross section of an extruder barrel 8 and a centre core 15 with a rotor 16. The rotor 16 rotates in the direction of the arrows 27 about a stationary centre core 15 and in relation to the stationary barrel 8. The centre core may in another embodiment of the invention be rotatable in one or both directions and with a fixed or with a variable rotational speed. The inner surface 14 of the barrel 8 and the outer surface 28 of the centre core 15 are heated and thus an emulsion of e.g. protein and fats will be processed to have a given structure/texture when forced through the ring shaped space 29 of the extruder 1. The rotor 16 is here seen as comprising two straight rectangular vanes 18, where the vanes constitute scraping means 17 having an inner and an outer scraping edge 31 for scraping the product from the inner surface 14 and the outer surface 28. It is thus the vanes 18 of the rotor 16, without any further means, that act as scraping means 17, where the scraping means 17 and scraping edges 31 actually are not in contact with the heated surface 28 or surfaces 14, 28 of the extruder 1, but operates in the vicinity of these surfaces 14, 28 according to the tolerances mentioned above.

[0173] In FIG. 3, the centre core 15 and a rotor 16, as seen in FIG. 2, are seen again but here without the barrel 8. The rotor 16 is arranged to be rotatable around the centre core 15 in order to allow the vanes 18 of the rotor 16 to act as scraping means 17 in order to scrape product from the heated surfaces 14, 28here only the outer surface 28 of the centre core 15 is seen. The end of the centre core 15 can be driven by a not shown motor, either directly or indirectly via a chain, a gear or a belt drive.

[0174] FIG. 4 shows an example of a centre core 15 with a rotor 16 having helically shaped scraping means 17. The scraping means 17 comprises several scraping blades/vanes/flights 30 and, at one end of the rotor 16, means is arranged for engagement with the drive means 19 seen in FIG. 1 and in FIG. 5. The scraping blades/vanes/flights 30 have a rather low flight height and the thickness will typically be between 2 and 12 millimetres, more preferably between 5 and 7 millimetres, and the width of the scraping blades/vanes/flights 30 will typically be between 10 to 60 millimetres. The thickness and the width can however be designed with other dimensions than mentioned.

[0175] In this figure, it can also be seen that the individual scraping blades/vanes/flights 30 are interconnected with stiffeners 32 between the individual blades/vanes/flights of the rotor 16 that allow a higher torque to be applied without overloading and deforming the rotor 16. Here three sets of stiffeners 32 are arranged along the rotor 16.

[0176] FIG. 5 shows an extruder 1 with a barrel 8 consisting of several barrel sections 9, 10, 11 along the length of the barrel 8 and with a dual drive system 33 at the ends of the rotor 16. The dual drive means are synchronised and operated via the drive means 19.

[0177] Connections 13 for steam, heated water or oil, or any other source of energy is connected to the barrel 8 and also to the centre core 15 via the connection 20. The barrel 8 has a product inlet 5 and a product outlet 22.

[0178] The stationary or rotatable centre core 15 and the barrel 8 have dimensions that create a rather narrow ring shaped space along the extruder 1, in which the rotor 16 is arranged with helical shaped scraping means 17 having a number of scraping blades/vanes/flights 30. A rotor 16 like the one seen in FIG. 5 can be used to partly urge the product from the product inlet 5 to the product outlet 22, but the rotor 16 can also be rotated in a counter acting direction, and thus used to create a counter pressure that in some applications can be useful. It is of course necessary with another energy source for forcing the product through the extruder 1at least if the rotor 16 is rotating in a counter direction or if the rotor 16 has straight scraping blades/vanes/flights 30. In this figure the product outlet 22 is seen as an annular shaped opening between the barrel 8 and the centre core 15. The product leaves the extruder 1 via this product outlet 22 and then falls into a container or onto a conveyornot shown.

[0179] FIG. 6 shows a rotor 16 with a central through-going shaft 34 for transferring torque. The rotor 16 has helically shaped scraping means 17 with flights/vanes 18 as also seen in FIG. 4. The central through-going shaft 34 extends from one end to the other end and is connected to the scraping means 17, which comprises several scraping blades/vanes/flights 30, at the ends in order to function as a torque shaft. This allows for a more shallow construction of the scraping means 17 as they do not have to carry the full torque during the extrusion process as the central through-going shaft may take up a considerable or even the main part of the torque applied to the rotor 16.

[0180] FIG. 7 shows a meat analogue product 35 produced using an extruder 1 and a method as described above. The product 35 has a layered structure comprising two outer layers 36 and a centre layer 37. The outer layers 36 are denser and the centre layer 37 is more open and loose in the structure/texture. This layered structure is possible to create due to the technique of the extruder described above, and the main issue is that the product is moved in relation to the barrel 8 as well as in relation to the centre core 15, and that this takes place in a rather narrow ring shaped interior having suitable temperature and other suitable conditions such as e.g. moisture content. This structure and the texture of the product 35 is very meat-like and serves as an example of a protein rich product 35, made from non-meat proteins, fats and carbohydrates. Also products made from meat proteins may obtain the same structure and texture.

[0181] FIG. 8 shows a rotor unit 38 comprising a centre core 15 with rotor 16 and two sets of drive means 19. The drive means are driven by an electric motor 39, but could as well be driven by any other type of motor. The electric motor 39 is here connected to the drive means by a first set of chain drive 40 and a second set of chain drive 41. Here chain drives 40, 41 are used, but belt, direct drive or gear drives or other types of drives could be used as well.

[0182] The first set of chain drive 40 drives the first rotor end part 42 and the second set of chain drive 41 drives the second rotor end part 43. In the area between the electric motor 39 and the chain drives 40, 41 a mounting flange 44 is seen, which is used to fasten the rotor unit 38 to the barrel of the extruder in order to make the extruder a complete and operable unit. Along the centre core 15 one vane 18 is seen.

[0183] FIG. 9 shows the same rotor unit as seen in FIG. 8, but from a different angle, where the first end part 42 and the second end part 43 and the one vane 18 is seen extending between said first and second end parts 42, 43. At the first rotor end part 42, the vane 18 is releasably arranged between catch means 45 in the shape of two protrusionsone on each side of the vane 18. At the second rotor end part 43 the vane 18 is also engaged via catch means 45, but here the catch means comprises only one protrusion which engages a cut out 46 in the end of the vane 18.

[0184] FIG. 10 shows the first end of the rotor unit 38 as seen in FIGS. 8 and 9, but here in an enlarged view, where the mentioned details are seen more detailed. At the lower side of the centre core 15 a second vane 18 is seen. This second vane 18 is installed and shaped like the already mentioned vane 18. This means that both of the first and second rotor end parts 42, 43 are designed having two sets of catch means 45 and it is also possible to have rotor end parts 42, 43 comprising more than two sets of catch means 45. Said catch means 45 may be identical or different shaped in order to receive vanes 18 having a corresponding shaped end.

[0185] FIG. 11 shows the second end of the rotor unit 38 as seen in FIGS. 8 and 9, but here in an enlarged view, where the mentioned details are seen more detailed. At this end of the rotor unit 38 a bolt end 47 is seen which allows the second rotor end part 43 to be uninstalled, replaced by another having different catch means 45 or loosened in order to dismount the vanes 18 of the rotor 16.

[0186] FIG. 12 shows a first end of the rotor unit 38, where there is a cut out in the drawing along the centre core 15 and rotor 16. In the centre of the centre core 15 a through-going shaft 34 is seen. Here the through-going shaft 34 serves two purposes, namely to provide steam to the interior of the centre core 15 via openings along the shaft, but also to transfer rotational torque from the drive means 19 to the second rotor end part 43, which also is seen in FIG. 13 where the second rotor end part 43 is seen.