Extrusion die

Abstract

There is provided an extrusion die which finds particular use in extrusion of extrudable products, and a method of producing an extruded product. The extrusion die comprises a conveyor having a receiving surface for receiving and drawing an extrudable material, a co-operative surface spaced over at least a portion of the receiving surface of the conveyor to define a passage between the receiving surface and the co-operative surface, the passage having an inlet side and an outlet side, whereby on operation of the conveyor, the receiving surface of the conveyor within the passage moves from the inlet side to the outlet side of the passage.

Description

EXTRUSION DIEPRIORITY DOCUMENTS

[0001] The present application claims priority from Australian Provisional Patent Application No. 2023903025 titled “EXTRUSION DIE ” and fded on 20 September 2023, the content of which is hereby incorporated by reference in its entirety.TECHNICAE FIELD

[0002] The disclosure generally relates to an extrusion die which finds particular use in extrusion of extrudable products, and a method of producing an extruded product.BACKGROUND

[0003] Recent developments in extrusion have allowed for the production of extruded protein products made from animal derived and / or non-animal derived protein sources that have oriented fibers that are texturally similar to meat. Although taste and texture of such extruded protein products is approaching that of meat, thus far the rate of production has been limited. Thus, there is a need for methods and systems that can be used to produce an extruded protein product having oriented fibers at more commercially acceptable rates.

[0004] Given the growing interest in the production of extruded protein products, considerable effort has gone into developing apparatuses and processes for their production. However, numerous challenges remain in order to provide apparatus and method that allows high throughput whilst producing a high- quality product at minimal cost.

[0005] The disclosure desirably addresses at least one shortcoming of the prior art and / or provides a useful alternative.SUMMARY

[0006] In a first aspect of the disclosure, there is provided an extrusion die comprising: a conveyor having a receiving surface for receiving and drawing an extrudable material; a co-operative surface spaced over at least a portion of the receiving surface of the conveyor to define a passage between the receiving surface and the co-operative surface; the passage having an inlet side and an outlet side, whereby on operation of the conveyor, the receiving surface of the conveyor within the passage moves from the inlet side to the outlet side of the passage.

[0007] In certain embodiments, the extrudable material is drawn directly or indirectly from an extruder, and / or from a distributor that receives extrudable material from the extruder.

[0008] In certain embodiments, the co-operative surface is spaced over the receiving surface at a fixed distance such that the passage has a fixed height from the inlet side to the outlet side.

[0009] In certain embodiments, the co-operative surface is a stationary surface.

[0010] In alternative embodiments, the extrusion die further comprises a second conveyor having a second receiving surface, and wherein the co-operative surface is the second receiving surface. In this alternative embodiment, the second receiving surface is configured to receive and draw the extrudable material.

[0011] In certain embodiments, a conveyor speed of the first conveyor and the second conveyor is independently controllable.

[0012] In certain embodiments, the extrusion die is configured to receive a web of material from at least one extruder over the receiving surface upstream from the inlet side of the passage.

[0013] In certain embodiments, the passage is configured to apply shear force to the extrudable material on conveyance of the extrudable material through the passage.

[0014] In certain embodiments, when in use, the movement of the receiving surface draws the extrudable material into and through the passage of the conveyor, and the receiving surface and / or the co-operative surface are configured to cool the extrudable material in the passage.

[0015] In certain embodiments, the receiving surface of the conveyor and / or the co-operative surface are configured to cool the extrudable material to a temperature of 100 °C or less at the outlet side.

[0016] In certain embodiments, the conveyor is a rotatable drum configured to rotate about a longitudinal axis thereof, and the receiving surface is an exterior surface of the rotatable drum.

[0017] In certain embodiments, the receiving surface has a width that extends in the direction of the longitudinal axis, and the co-operative surface extends over at least the width of the receiving surface. In certain embodiments, the extrusion die is configured to receive a web of the extrudable material over the width of the receiving surface upstream from the inlet side of the passage.

[0018] In certain embodiments, the extrusion die further comprises a stationary outer drum segment that encloses at least a portion of the rotating drum, and the co-operative surface is an internal surface of thestationary outer drum. In certain embodiments, the stationary outer drum segment is in the form of an arc with arc length of from about 90 degrees up to about 270 degrees. More preferably, the arc length is from about 120 degrees to about 240 degrees.

[0019] In certain embodiments, the passage is sized to induce shear stresses in the extrudable material, e.g. to shear align fibrous components within the extrudable material.

[0020] In a second aspect of the disclosure, there is provided an extrusion system comprising: the extrusion die according to the first aspect of the disclosure and / or embodiments and / or forms thereof; the extruder; and a distributor located downstream of the extruder and upstream of the extrusion die, the distributor configured to receive the extrudable material from the extruder and distribute the extrudable material in the form of a uniform or non-uniform stream to the receiving surface.

[0021] In certain embodiments, the extrusion die is configured to draw extrudable material directly or indirectly from an extruder, and / or from a distributor that receives extrudable material from the extruder.

[0022] In certain embodiments, the distributor is configured to cool the extrudable material.

[0023] In certain embodiments, the distributor comprises structure to separate the stream into a plurality of sub-streams.

[0024] In certain embodiments, the distributor comprises one or more passages from an inlet to an outlet thereof, to distribute the extrudable material in the form of one or more streams.

[0025] In certain embodiments, the distributor distributes the extrudable material in the form of a sheet.

[0026] In certain embodiments, the distributor further comprises a static mixer, the static mixer configured to introduce one or more additives into the extrudable material.

[0027] In certain embodiments, the distributor is wedge shaped such that the distributor narrows in height in a direction from the extruder to the extrusion die whilst increasing in width. In an alternative embodiment, the distributor is cone shaped such that the distributor narrows in height and width in a direction from the extruder to the extrusion die.

[0028] In certain embodiments, the extrudable material is a protein composition. In certain embodiments the protein composition is in the form of a protein paste. In forms of the disclosure that include a staticmixer to introduce one or more additives, suitable additives include fat, flavouring agents, nutrients, preservatives, texture modifying agents, and combinations thereof.

[0029] In a third aspect of the disclosure, there is provided a method of forming an extruded product using the extrusion die or system of the first or second aspects of the disclosure and / or embodiments and / or forms thereof, the method comprising: drawing the extrudable material with the conveyor; conveying the extrudable material through the passage to subject the extrudable material to shear forces to shape the extrudable material; cooling the extrudable material within the passage; and discharging the extrudable material from the extrusion at the outlet side of the passage as the extruded product.

[0030] In certain embodiments, the drawing step comprises drawing the extrudable material directly or indirectly from the extruder, and / or from a distributor that receives extrudable material from the extruder.

[0031] In certain embodiments, the extrudable material comprises one or more of: a protein, a carbohydrate, a starch, a gum, a fibrous material, a gelling agent; and / or is a protein composition, a carbohydrate composition, or a starch composition.

[0032] In certain embodiments, the extrudable material is a protein composition.

[0033] In certain embodiments, the protein composition has a protein content of from about 5 wt % up to about 100 wt% based on dry weight of the protein composition. In certain embodiments, the protein composition has an initial moisture content of at least 25 wt% based on the total weight of the protein composition.

[0034] In a fourth aspect of the disclosure, there is provided a method of extruding an extrudable material, the method comprising: drawing the extrudable material with a conveyor; conveying the extrudable material through a passage formed between an exterior surface of the conveyor and a co-operative surface spaced over at least a portion of the exterior surface; operating the exterior surface of the conveyor and / or the co-operative surface to cool the extrudable material in the passage.

[0035] In certain embodiments, the co-operative surface is a stationary surface.

[0036] In alternative embodiments, the co-operative surface is a non-stationary surface. That is, in one or more forms, the co-operative surface is a conveyor surface of a second conveyor.

[0037] In certain embodiments, a conveyor speed of the exterior surface and the co-operative surface is each independently configured.

[0038] In certain embodiments, the extrudable material is drawn directly or indirectly from an extruder and / or from a distributor that receives extrudable material from an extruder.

[0039] In an embodiment, the extrudable material comprises one or more of: a protein , a carbohydrate, a starch, a gum, a fibrous material, a gelling agent; and / or is a protein composition, a carbohydrate composition, or a starch composition.

[0040] In an embodiment, the extrudable material is a protein composition.

[0041] In certain embodiments, the protein composition has a protein content of from about 5 wt % up to about 100 wt% based on dry weight of the protein composition. In certain embodiments, the protein composition has an initial moisture content of at least 25 wt% based on the total weight of the protein composition.

[0042] In certain embodiments, the protein composition is in the form of a protein paste.

[0043] In certain embodiments, the protein composition comprises fibrous protein.

[0044] In certain embodiments, the extrudable material is cooled to a temperature of 100 °C or less.

[0045] In certain embodiments, the conveyor is a rotating drum configured to rotate about a longitudinal axis thereof.

[0046] In certain embodiments, the method comprises rotating the extrudable material through the passage along an arc about the longitudinal axis.

[0047] In certain embodiments, the step of conveying the extrudable material through the passage further comprises subjecting the extrudable material to shear forces. Preferably the shear forces induce shear alignment of fibrous components within the extrudable material.

[0048] In certain embodiments, the extrudable material is cooled during the step of distributing the extrudable material.

[0049] In certain embodiments, prior to the step of drawing the extrudable material from the extruder, the method further comprises distributing the extrudable material uniformly or non-uniformly over a width of the conveyor, e.g. in the form of one or more streams.

[0050] In certain embodiments, the method further comprises using a static mixer to mix one or more additives into the extrudable material prior to distributing the protein composition onto the conveyor. Suitable additives, particularly in the context of the extrudable material being an edible material, include fat, flavouring agents, nutrients, preservatives, texture modifying agents, and combinations thereof.

[0051] In a fifth aspect, there is provided an extruded material formed using the method of the third or fourth aspect.

[0052] In yet another aspect of an embodiment of the disclosure, there is provided an extrusion die comprising: a conveyor having a receiving surface for receiving and drawing an extrudable material; a co-operative surface spaced over at least a portion of the receiving surface of the conveyor to define a passage between the receiving surface and the co-operative surface; the passage having an inlet side and an outlet side, whereby on operation of the conveyor, the receiving surface of the conveyor within the passage moves from the inlet side to the outlet side of the passage; and wherein either or both of the receiving surface of the conveyor or the co-operative surface is configured to be cooled.

[0053] In certain embodiments, either or both of the receiving surface of the conveyor or the cooperative surface is configured to be cooled by temperature regulation. The temperature regulation may involve conduction cooling, convection cooling or both.

[0054] Further aspects of the present disclosure and further embodiments of the aspects described in the preceding paragraphs will become apparent from the following description, given by way of example and with reference to the accompanying drawings.BRIEF DESCRIPTION OF DRAWINGS

[0055] Figure 1 is a side view schematic illustrating an extrusion system for preparing a protein product in accordance with one embodiment of the disclosure.

[0056] Figure 2 is a top-down schematic illustrating the distribution of protein onto the extrusion die of the system of Figure 1.

[0057] Figure 3 is an illustration showing three different embodiments (A), (B), and (C) for loading the extrusion die of the disclosure with an extrudable material.

[0058] Figure 4 is a side view schematic illustrating an extrusion system for preparing a protein product in accordance with another embodiment of the disclosure.

[0059] Figure 5 is a side view schematic illustrating an embodiment of the distributor of an extrusion system for preparing a protein product in accordance with another embodiment of the disclosure.

[0060] Figure 6 is a top-down schematic illustrating the distribution of protein onto the extrusion die of the system of Figure 1 and further comprising an embodiment of a partition.

[0061] Figure 7 is a graph comparing the chewiness (A), juiciness (B), hardness (C) and tenderness (D) of extrudates produced using an embodiment of the extrusion die of the disclosure, extrudates using a conventional die and chicken.

[0062] In the following description, like reference characters designate like or corresponding parts throughout the figures.DESCRIPTION OF EMBODIMENTS

[0063] The disclosure broadly relates to an extrusion die for forming an extruded product, and in particular an extruded protein product which may be formed from animal and / or plant-based protein sources. The disclosure also relates to systems and methods including such an extrusion die.

[0064] The inventors have developed an extrusion die which comprises a conveyor to draw an extrudable material from at least one extruder and which forms part of a cooling passage for subsequently cooling subjecting the extrudable material to shear stresses to form an extruded product. In a significant departure from conventional extrusion dies in which the extrudable material is subjected to compressive forces and pressure driven through an extrusion die, the extrusion die of the disclosure draws extrudable material from at least one extruder (eg via distributor) under tension or zero pressure.

[0065] This arrangement has a number of benefits including scalability and improved product quality. In particular, since the extrusion die of the disclosure draws material from the extruder, it can achieve a much higher throughput for a given extrusion pressure. The only pressure required for the extruder is that to overcome the resistance of the distributor. Further, drawing the extrudable material from the extruder (eg via a distributor) places it under tension which advantageously induces shear alignment of any fibrous components in the extrudable material.

[0066] Still further, since the extrudable material is not pressure driven through the extrusion die, the extrusion die is not designed to minimise pressure drop. Instead, extrusion dies of different designs may be used, for example, extrusion dies which can process the extrudable material over large surface areas as compared with convention extrusion dies. This is particularly beneficial since it allows for rapid cooling of the extrudable material and thus increases the throughput / production rate.

[0067] The disclosure is described below in relation to a preferred embodiment thereof, and in particular for processing protein composition in the form of a protein paste. Although the example referred to below refers to protein paste, the skilled person will appreciate that the extrusion die and method can generally be applied to any extrudable material. Preferred extrudable materials are those that comprise a fibres or a fibrous component since, as discussed below, the extrusion die and methods advantageously result in shear alignment of fibres or the fibrous component of the extrudable material. Notwithstanding this, particularly preferred extrudable materials include edible and non-edible materials which include a protein, a carbohydrate, a starch, a gum, a fibrous material, a gelling agent, and the like; or a protein composition, a carbohydrate composition, or a starch composition comprising one or more of the foregoing. In certain embodiments, the extrudable material is a protein composition, such as a protein paste. In other embodiments, the extrudable material is a polymer (eg nylon, polycarbonate, acrylonitrile butadiene styrene), polymer blend (eg acrylonitrile butadiene styrene and polycarbonate, nylon and polybutylene terephthalate, polypropylene and polyethylene, polyamide and polyethylene, or polycarbonate and polybutylene terephthalate), thermoplastic elastomer (eg styrene block copolymers, polyether block amides, polyolefin elastomers, thermoplastic polyurethane, chlorinated polyethylene), fibre reinforced composite (eg glass, carbon fiber or aramid fibre reinforced polypropylene or nylon), or non-woven fabric.

[0068] Figure 1 is a side view schematic illustrating an extrusion system 100 according to an embodiment. Extrusion system 100 comprises an extruder 102 and extrusion die 103 for preparing a protein product in accordance with one embodiment of the disclosure. The extruder 102 with breaker plate 104 provides a source of protein paste 106 to extrusion die 103 via distributor 114. As is shown, distributor 114 is located downstream of the extruder 102 and upstream of the extrusion die 103.

[0069] In this embodiment, extrusion die 103 comprises a conveyor, shown here in the form of a rotatable inner drum 108, and stationary outer drum segment 110. In the present case, the receiving area of rotatable drum 108 provides a receiving surface 116. In this embodiment, the rotatable inner drum 108 has a diameter of 200mm. However, the person skilled in the art would appreciate that the rotatable inner drum 108 could have a different diameter, such as between about 100 mm and about 1000 mm, or between about 200 mm and 600mm. Stationary outer drum segment 110 has a co-operative surface 118 which is spaced over at least a portion of the receiving surface 116 of the rotatable drum 108 to define a passage between the receiving surface 116 and the co-operative surface 118.

[0070] The distributor 114 is configured to receive the protein paste 106 from the extruder 102 and distribute the protein paste 106 to the receiving surface 116 as a uniform or non-uniform stream. During operation, protein paste 106 is discharged from extruder 102 and spread over a receiving surface 116 of rotatable drum 108 via breaker plate 104 and the distributor 114. In other embodiments, protein paste 106 is discharged from extruder 102 and spread over a receiving surface 116 of rotatable drum 108 and the distributor 114, without a breaker plate 104. The person skilled in the art would understand that a breaker plate may be required for certain extrudable materials that may form clumps or agglomerations, such as a protein paste. Protein paste 106 is typically in the form of a composition having a protein content of from about 5 wt% to about 100 wt% on a dry basis, a total moisture content of at least 25 wt%.

[0071] The passage of the illustrated embodiment has an inlet side and an outlet side whereby, on operation of the rotatable drum 108 (being the conveyor) under the control of a suitable drive system, such as a motor (not shown), the receiving surface 116 of the rotatable drum 108 within the passage moves from the inlet side to the outlet side of the passage to draw the protein paste 106 into and through the passage. In certain embodiments, the receiving surface 116 and / or the co-operative surface 118 are configured to cool the extrudable material in the passage, in which case the extrusion die acts as a “cooling die”. In certain embodiments, the receiving surface 116 and / or the co-operative surface 118 may be configured as a temperature-regulated surface for the cooling the protein paste 106 during production of a product from the protein paste 106. After passing through extrusion die 103, the protein product is withdrawn via conveyor belt 112.

[0072] The interaction between the receiving surface 116, the co-operative surface 118 and the protein paste 106 will be described in more detail below.

[0073] In the illustrated embodiment, rotatable drum 108 rotates in the clockwise direction to draw protein paste 106 from extruder 102. That is, in the present case the rotatable drum 108 applies a pulling force which draws protein paste 106 from extruder 102. The applied pulling force will depend on the viscosity and strength of the protein paste 106. For example, the applied pulling force will be higher if the paste 106 is very viscous and strong compared to the applied pulling force required if the protein paste 106 is less viscous and weak. This arrangement marks a distinct contrast with conventional extrusion processes where protein paste is driven through an extrusion die under pressure from the extruder. One issue with conventional systems is that the throughput of these systems is limited by the required pressure.

[0074] In contrast, in extrusion systems (such as system 100) comprising an extrusion die according to an embodiment of the disclosure, the conveyer (shown in Figure 1 as rotatable drum 108) assists to draw protein paste 106 from extruder 102. As a result, in the present extrusion die, the throughput is lessreliant on increasing pressure within the extruder 102. Instead, throughput can by increased by increasing the speed of rotatable drum 108. In use, the speed of the rotatable drum 108 in the illustrated embodiment is between about 1 rpm and about 5 rpm. Typically, the speed of the rotatable drum 108 will be controlled so as to approximately match the speed at which the protein paste 106 exits the extruder 102. In embodiments, the speed of the rotatable drum 108 may be adjusted to either match the throughput of the extruder 102, or so that the protein paste 106 can be pulled from the extruder 102 without accumulation at an outlet of the distributor 114. This allows higher throughput at much lower extrusion pressures than in comparison with conventional systems which leads to better scalability. For example, in the system 100 shown in Figure 1 throughput can be increased by either increasing the speed of rotatable drum 108 or by increasing the surface area of the receiving surface of rotating drum 108. In conventional systems, it is difficult to scale production by increasing the size of the extrusion die since this increases the pressure drop required to drive protein paste through the extrusion die.

[0075] Further, in view of the above discussion, another advantage of the present disclosure is that the protein paste 106 is not exposed to high compressive pressures used in conventional extrusion dies which may have a deleterious effect on protein paste 106. In contrast, the pulling force can advantageously induce shear alignment of fibres within protein paste 106.

[0076] A further advantage with this arrangement is that the rotational speed of rotatable drum 108 can be varied to alter physical characteristics of the resultant protein extrudate (being the protein product). By way of example, the rotational speed of rotatable drum 108 can be used to control porosity of the protein extrudate produced from protein paste 106. In more detail, the drawing force applied to the protein paste 106 via rotatable drum 108 causes protein paste 106 to be subjected to a pressure drop at the end of paste distributor 114. This pressure drop can be controlled to facilitate balloon-puffing of protein paste 106 wherein a porous structure is created within protein paste 106 through high pressure / temperature water flash off. The magnitude of this pressure drop, and in turn the porosity of the resulting protein extrudate, can be controlled via the rotational speed of rotatable drum 108. Advantageously, with this arrangement, balloon-puffing can be achieved without the injection of additional gasses as per some conventional systems, thus enhancing process flexibility and throughput whilst minimising cost.

[0077] Before continuing further, although Figure 1 illustrates an extrusion system 100 comprising an extrusion die 103 having a stationary surface (being the co-operative surface 118) which cooperates with a receiving surface 116 of a rotatable drum 108 which is driven by a drive system, such as a motor (not shown), the disclosure is not limited to this configuration. Another embodiment of the present disclosure, which will be described in more detail below, provides an extrusion die comprising a passage or channel having a receiving surface and a co-operative surface which are both non-stationary. In such an embodiment, the receiving surface may be a surface having a speed which is controlled by a motor and the co-operative surface may be a surface having a speed which is imparted as a result of adhesion toprotein paste which is being drawn through passage or channel. It is also possible that both the receiving surface and the co-operative surface may comprise a surface having a speed which is controlled by a motor (or respective motors) to establish a required speed and speed differentiation therebetween. In such a case, establishing the required speed and speed differentiation therebetween may involve independent control of the speed of the receiving surface and the co-operative surface.

[0078] In embodiments, the receiving surface 116 and the co-operative surface 118 interact such that the extrudable material is subjected to shear forces as the extrudable material passes through the passage defined therebetween.

[0079] Returning now to the illustrated embodiment in Figure 1, protein paste 106 is drawn by the clockwise rotation of rotatable drum 108 through the passage or channel formed between the receiving surface 116 of rotatable drum 108 and the co-operative surface 118 spaced over the rotatable drum 108, which in this embodiment is a stationary surface of the underside of outer drum segment 110.

[0080] In the present case, the rotatable drum 108 is driven by a suitable drive system, such as a motor (not shown), which is controllable to provide a desired speed. The rotatable drum 108 shown here is configured to rotate about a central axes thereof, and the receiving surface 116 is an exterior surface of the rotatable drum 108. The receiving surface 116 has a width that extends in the direction of the central axes, and the co-operative surface 118 extends over at least the width of the receiving surface.

[0081] The illustrated extrusion die 103 receives a web of protein paste 106 originating from the extruder 102 over the receiving surface 116 from the inlet side of the passage. It will be appreciated that although Figure 1 shows the protein paste 106 as being drawn from a distributor 114 that receives protein paste 106 from the extruder 102, in other embodiments it is possible that the protein paste 106 may be drawn directly from the extruder 102. In other non-illustrated embodiments, the extrusion die is configured to receive a web of material from a plurality of extruders, eg, two or three, over the receiving surface upstream from the inlet side of the passage.

[0082] Rotatable drum 108 is nestled within stationary outer drum segment 110 such that the central axes of rotatable drum 108 and stationary outer drum segment 110 are aligned. In this way, the height of the passage (being the distance between the receiving surface 116 of rotatable drum 108 and stationary outer drum 110) is constant over the arc length of the passage between an inlet and outlet thereof. That is, the co-operative surface 118 is spaced over the receiving surface 116 at a fixed distance such that the passage has a fixed height from the inlet side to the outlet side.

[0083] The passage may be configured to apply shear force to the protein paste 106 on conveyance of the protein paste 106 through the passage. For example, the passage may be sized to induce shear stressesin the protein paste 106. The passage height may be selected to impart shear force to protein paste 106 which promotes the formation of a fibrous structure and / or promotes shear alignment of fibrous components of protein paste 106. A suitable passage height is typically from about 5 mm to about 50 mm, and a suitable passage width is typically from about 20 mm. The passage width may be selected based on the desired width of the protein extrudate. Whilst there is no particular maximum width for the passage, a suitable width may be up to about 500 mm. In this example, the arc length of the passage is about 180 degrees. However, an arc length of from about 90 degrees to about 270 degrees may be useful.

[0084] In embodiments, the stationary outer drum segment 110 is in the form of an arc with arc length of from about 90 degrees up to about 270 degrees. The arc length may also be from about 120 degrees to about 240 degrees.

[0085] Continuing now with reference to Figure 1, in the present case the receiving surface 116 of rotatable drum 108 and the co-operative surface 118 (being an internal facing surface) of stationary outer drum segment 110 are independently configured to operate at a temperature which cools the protein paste 106 during production of the protein product. This arrangement differs from conventional systems where cooling usually occurs within the extruder and / or extrusion die. The arrangement of the disclosure is advantageous since it promotes rapid cooling of protein paste 106 during shear alignment, and again allows for higher throughput. Typically, the protein paste 106 is provided to rotatable drum 108 at temperatures greater than 100 °C, such as at temperatures of up to 180 °C, and protein paste 106 is rapidly cooled to temperatures of 100 °C or less through both steam flash off and cooling surfaces of inner and outer drums. To facilitate cooling of the protein paste 106, in certain embodiments, a temperature of either or both of the receiving surface of the conveyor and / or the co-operative surface is regulated at between about 50°C and about 100°C, such as between about 55°C and about 85°C, or about 60°C and about 80°C. In particular embodiments, a temperature of either or both of the receiving surface of the conveyor and / or the co-operative surface is regulated at about 55 °C, about 60°C, about 65 °C, about 70°C, about 75°C, about 80°C, about 85°C or about 90°C, or any range between these temperatures.

[0086] Although not shown in the embodiment depicted in Figure 1, the receiving surface 116 of the rotatable drum 108 and / or the co-operative surface 118 may be configured to cool the protein paste 106 to a temperature of 100 °C or less at the outlet side, with the actual temperature depending on the production requirements for the protein product.

[0087] For example, for the production of certain protein products, the receiving surface 116 of the conveyor and / or the co-operative surface 118 are configured to cool the protein paste 106 to a temperature of about 85 °C to about 55 °C at the outlet side. For the production of other proteinproducts, the receiving surface 116 of the conveyor and / or the co-operative surface 118 are configured to cool the protein paste 106 to a temperature of about 80 °C to about 60 °C at the outlet side.

[0088] As described above, in certain embodiments the temperature of the receiving surface 116 of the rotatable drum 108 and / or the co-operative surface 118 may be regulated by suitable temperature regulating means to cool the protein paste as it passes through the passage, such as by conduction cooling, convection cooling or both. Examples of suitable temperature regulating means include electric temperature regulation, forced air temperature regulation, ambient air temperature regulation, liquid flow temperature regulation, steam temperature regulation or combinations thereof. One example of a suitable means comprises a jacket fdled with temperature-controlled air, liquid or steam to set or modify the temperature of either or both of the receiving surface 116 of the rotatable table 108 and / or the cooperative surface 118. Another example of a suitable means comprises a resistive element(s) for regulating the temperature of either or both of the receiving surface of the conveyor and / or the cooperative surface using an electrical power source.

[0089] Returning again now to Figure 1, after exiting the passage, the protein extrudate is discharged from rotatable drum 108, onto, for example, conveyor belt 112 for packing. However, the skilled person will appreciate that the use of conveyor belt 112 is optional and other means for removing the protein extrudate, or further processing the protein extrudate, may be employed. It is also possible that the temperature of conveyor belt 112 may also be controlled to further cool the protein extrudate, via conduction cooling, convection cooling or both. Examples of suitable cooling techniques include forced air cooling or blast chilling.

[0090] In the present case, the receiving surface 116 of rotatable drum 108 and the internal facing surface of stationary outer drum segment 110 are each formed of a material having a high thermal conductivity. In the illustrated embodiment, the receiving surface 116 of rotatable drum 108 and the internal facing surface of stationary outer drum segment 110 are each formed of a stainless steel. However, it will be appreciated that either or both of the receiving surface 116 of the rotatable drum 108 or the co-operative surface 118 may be formed of any suitable material having a high thermal conductivity. Other examples of suitable thermally conductive materials include, e.g., a metal or non- metal, such as copper, boron nitride, silicon carbide, polyetherimide or poly ethersulfone. The thermally conductive material may also be coated, for example, with a food-safe polymer.

[0091] In Figure 1, the receiving surface 116 of rotating drum 108 and the co-operative surface 118 of stationary outer drum segment 110 each have a surface texture or finish which imparts a desired shear alignment of the protein paste. The person skilled in the art could readily modify the surface texture or finish to achieve a desired level of adhesion to thereby modify the shear alignment. In the present case, the receiving surface 116 of rotatable drum 108 and the co-operative surface 118 of stationary outer drumsegment 110 are a polished stainless steel. However, the receiving surface 116 of the conveyor and the co-operative surface 118 may be configured to provide different surface textures or finishes.

[0092] Figure 2 shows the use of distributor 114 to spread protein paste 106 over a large surface area. This is useful since the drawing force provided by rotatable drum 108 allows higher throughput of protein paste 106. More broadly, the extrusion die 103 may be configured to draw protein paste 106 (ref. Figure 1) directly or indirectly from the extruder 102, and / or from a distributor 114 that receives extrudable material from the extruder 102. The distributor 114 may be configured to cool the extrudable material. For example, the distributor 114 may be configured to cool the extrudable material to, eg, 150, 140, 130, 120, 115, 110, 105, 100, 95, 90, 85, 80, 75, or 70 °C, or any temperatures in between.

[0093] In the present case, distributor 114 provides a substantially uniform flow of protein paste 106 to rotatable drum 108. However, it is possible that a distributor 114 which provides a non-uniform flow of protein paste 106 to rotatable drum 108 could be used e.g., by splitting protein paste 106 into two or more sub-streams.

[0094] In some embodiments, distributor 114 is configured to pre-align portions of streams or substreams of protein paste 106 to facilitate texturisation. The provision of a differentiated flow field within the passage may assist in the formation of a fibrous protein structure and can thus be used to improve the texture of manufactured meat or meat-like products.

[0095] In other non-illustrated embodiments, the distributor 114 comprises a structure which separates the stream into a plurality of sub-streams. For example, the distributor 114 may comprise one or more passages from an inlet to an outlet thereof, which distribute the protein paste 106 in the form of one or more streams. It is also possible that the distributor 114 may be configured to distribute the protein paste 106 in the form of a sheet. The thickness of the sheet can be 5 mm to 50 mm and the sheet can then be cut or stamped to mimic whole cut meat.

[0096] As shown in Figures 1 and 2, distributor 114 attaches at a first end thereof to an outlet of extruder 102 and at a second end thereof to rotatable drum 108 at the inlet to the passage.

[0097] The distributor 114 shown here has a wedge shaped form which narrows in height whilst increasing in width from extruder 102 to extrusion die 103. The effect of this is that protein paste 106 is formed into a thin sheet which is drawn from distributor 114 via rotation of rotatable drum 108. As discussed above, distributor 114 may be configured to provide protein paste 106 in the form of a single sheet or in the form of plural sub-streams.

[0098] Where the distributor 114 is configured to provide protein paste 106 as plural sub-streams, the sub-streams may be in the form of sheets, threads, strands, of the protein paste 106. It will thus be appreciated that the distributor 114 may have a single channel or passage passing from the inlet and outlet thereof to provide protein paste 106 as a single stream or, alternatively, the distributor 114 may include multiple channels, which are created by mechanical means or by introducing a different stream of materials, such as fat or flavoured gels, or passages passing from the inlet to the outlet thereof to provide protein paste 106 in multiple sub-streams.

[0099] In an alternative embodiment, distributor 114 is cone shaped such that it both narrows in height and width from extruder 102 to extrusion die 103. The effect of this is that protein paste 106 is formed into a strand or filament which is drawn from distributor 114 via rotation of drum 108.

[0100] In some embodiments, distributor 114 includes a static mixer (not illustrated). The static mixer can be configured to partially or completely mix an additive into protein paste 106. A non-limiting disclosure of additives includes fat, flavouring agents, nutrients, preservatives, texture modifying agents, and the like and combinations thereof.

[0101] The distributor 114 may have an internal surface having a surface texture or finish which imparts a desired stable flow of the protein paste 106. As would be appreciated by the person skilled in the art, a rough surface texture may increase friction and / or cause pressure build up and sudden pressure release. The person skilled in the art could readily modify the surface texture or finish to achieve a desired level of flow. In certain embodiments, the internal surface of the distributor 114 is formed of a polished stainless steel.

[0102] Figures 3A-3C illustrate different configurations for loading of the rotatable drum 108 shown in Figure 1 and Figure 2 with protein paste 106. In Figure 3A, rotatable drum 108 receives protein paste 106 tangentially to the receiving surface 116, before rotating protein paste 106 through the passage formed between the receiving surface 116 of rotatable drum 108 and the stationary co-operative surface 118 on the underside of outer drum segment 110 about an arc of about 180 degrees.

[0103] In Figure 3B, rotatable drum 108 receives protein paste 106 normally to the receiving surface 116, before rotating protein paste 106 through the passage about an arc of about 180 degrees.

[0104] In Figure 3C, rotatable drum 108 receives protein paste 106 normally to the receiving surface 116, before rotating protein paste 106 through the passage about an arc of about 270 degrees.

[0105] Figure 4 is a side view schematic illustrating an extrusion system according to another embodiment of the present disclosure. The extrusion system shown here comprises an extruder 102 andextrusion die 400 for preparing a protein product in accordance with an embodiment of the disclosure. The extruder 102 with breaker plate 104 provides a source of protein paste 106 to the extrusion die 400. For simplicity, extruder 102, breaker plate 104, and protein paste 106 are the same as illustrated in the embodiment of Figure 1. However, the skilled person will appreciate that different extruder, breaker plate, and extrudable material could be used.

[0106] In the embodiment in Figure 4, extrusion die 400 comprises first conveyor 402 and second conveyor 404 with a channel formed therebetween. First conveyor 402 and second conveyor 404 each have corresponding first and second receiving surfaces 406, 408 for drawing protein paste 106 from extruder 102 through the channel under controllable shear and cooling conditions to an outlet to provide an extruded product at an outlet of the channel. As such, in this embodiment the extrusion die 400 has a second conveyor 404 having a second receiving surface 408 which co-operates with the first receiving surface 406 and which is a non-stationary surface. In the present case, the first conveyor 402 is a lower conveying belt and the first receiving surface 406 is a surface of the first conveying belt 402 which is driven by a motor (not shown). The second conveyor 404 is an upper conveying belt having a receiving surface 408 (which is a co-operative surface) in the form of a surface of the second conveying belt which overlies the first receiving surface 406 and which, in the illustrated embodiment, is not driven but is free to rotate.

[0107] First conveyor 402 and second conveyor 404 may be configured to be operated and / or controlled independently such that each conveyor 402, 404 may be operated at a different speed. In this way, the speed of the upper conveying belt and the lower conveying belt can be controlled independently so as to create a desired differentiated speed between receiving surfaces 406, 408 to generate controllable shearing of protein paste 106 between receiving surfaces 406, 408. In this embodiment, the desired differentiated speed is established by setting the speed of the first conveyer to 2 metres / minute and the speed of the second conveyor 404 to 1 metre / minute. Typically, the speed of the first conveyor 402 will approximately match the speed at which the protein paste 106 exits the extruder 102 via the distributor 114. In embodiments, the speed of the first conveyor 402 may be adjusted to either match the throughput of the extruder 102 (eg via the distributor 114), or so that the protein paste 106 can be pulled from the extruder 102 (eg via the distributor 114) without accumulation at an outlet of the distributor 114. In certain embodiments, the speed of the first conveyor is between 0.5 and 5 metres per minute. In certain embodiments, the speed of the second conveyor is between 0.25 and 5 metres per minute.

[0108] The use of differentiated conveyance speed may be beneficial since applying differentiated conveyance speed between the first and second receiving surfaces 406, 408 can be used to control the shear forces applied to the extrudable material. The differentiated speed may be established by driving one conveyor using a suitable motor and allowing the other conveyor to “idle”. In certainembodiments, the speed of the idling conveyor is determined by the adhesion of the protein paste to the respective receiving surfaces 404, 408 and the tensile force applied to the protein paste.

[0109] In the illustrated embodiment, it is the first conveyor 402 which is driven by a suitable motor and the second conveyor 404 which is passively “dragged” by the protein paste. In this arrangement, adhesion of the protein paste to the receiving surface 408 of the second conveyor 404 determines the speed of the second conveyor 404. However, in certain embodiments, it is possible that both the first conveyor 402 and the second conveyor 404 are driven by a suitable motor which is controlled to provide the differentiated conveyance speed between the first conveyor 402 and the second conveyor 404 to receive and draw the extrudable material into the passage or channel.

[0110] As with the embodiment illustrated in Figure 1, in this embodiment, the corresponding first and second receiving surfaces 406, 408 are configured to cool the protein paste as it passes through the passage or channel. In this embodiment, the cooling comprises exposure of the first and second receiving surfaces 406, 408 to ambient conditions. However, in other embodiments, the corresponding first and second receiving surfaces 406, 408 may be each independently configured to be cooled by a suitable temperature regulating means. Examples of suitable temperature regulating means are described elsewhere in this disclosure. The temperatures may be as described elsewhere in this disclosure.

[0111] In the present case, extrusion die 400 (or extrusion system) also includes first and second carriers 410, 412 (being an upper and lower carrier respectively) to introduce or apply a film 414 to the external surfaces of protein paste 106 as the protein paste enters the passage. In this way, the extruded product exits the passage encased or sealed in a packaged form which minimises potential for contamination. Although in the present case there are first and second carriers 410, 412 which introduce or apply a film 414 to the external surfaces of protein paste 106 as the protein paste enters the passage, in other arrangements it is possible that one or more carriers may introduce or apply a film to an external surface of the protein paste as the protein paste exits the passage. The person skilled in the art could readily select a suitable material for the film, such as polyester, polypropylene, polyethylene terephthalate glycol, or silicone. The film could be laminated or coated to enhance moisture or oxygen resistance.

[0112] Figure 5 is a side view schematic illustrating an embodiment of a distributor 114 suitable for use with an extrusion system according to an embodiment of the disclosure. The distributor 114 shown here has a restriction 502 to modify the pressure of the protein paste 106 within the distributor 114.

[0113] The pressure of the protein paste 106 is higher upstream of the restriction and is lower downstream of the restriction 502. A direction of flow is indicated by the arrow in Figure 5. The effect ofthe restriction 502 is to generate a sudden pressure drop to facilitate expansion within the distributor. The sudden decrease in pressure decreases the solubility of gases, such as steam. The result is the formation of gas bubbles 504 within the protein paste 106. A person skilled in the art could readily adjust the size of the restriction 502, and the remaining channel within the distributor 114, to control excessive steam flash off and modify texture (eg, form gas bubbles 504, also known as “balloon-puffing” of the protein paste to create a porous structure through high pressure / temperature water flash off).

[0114] In other non-illustrated embodiments, the distributor has substantially straight walls or tapered walls without a restriction. In these embodiments, a sudden decrease in pressure may be achieved by a sudden increase in cross section areas between the distributor outlet and the inlet of the extrusion die passage. This may have the same effect of decreasing the solubility of gases, such as steam, and result in the formation of gas bubbles.

[0115] Figure 6 is a top-down schematic illustrating a distribution of a protein paste 106 onto the extrusion die of the system 100 of Figure 1 and further comprising a partition 602 and adjuster 604.

[0116] The partition 602 shown here is adjustably positioned between the receiving surface 116 and the co-operative surface 118 to limit a width of the passage. In the present case, by suitable adjustment of the adjuster 604, the position of the partition 602 is adjustable co-axially with the central axes of the rotatable drum 108. Partition 602 is configured to limit the width of the receiving surface 116 and hence the passage or channel formed between the receiving surface 116 and the co-operative surface 118. In the illustrated embodiment, the adjuster 604 is a threaded rod. In alternative embodiments, the adjuster 604 may take any suitable form that allows the position of the partition to be adjusted, such as a hydraulic ram, gear mechanism or rack and pinion.

[0117] By allowing the position of the partition 602 to be adjusted and set by an adjuster (or adjustment means) the width of the passage may be selected or set to provide a desired width of the protein paste 106. As mentioned elsewhere herein, a suitable passage width is typically from about 20 mm. Whilst there is no particular maximum width for the passage, a suitable width may be up to about 500 mm.

[0118] Before continuing further it is to be appreciated that although the partition 602 is illustrated with reference to Figure 6 and the system 100 of Figure 1, the partition 602 may be applied to other embodiments to achieve the same effects. For example, and with reference to the first and second conveying belts illustrated in Figure 4, the extrusion die 400 may comprise a partition between the receiving surface and the co-operative surface of the belts to limit a width of the passage. In other nonillustrated embodiments, the extrusion die may comprise a plurality of partitions with at least one of the partition fixed or independently adjustable.

[0119] Embodiments of the present disclosure also provide a method of forming an extruded product using an extrusion die or system according to an embodiment. In general terms, a method according to an embodiment comprises drawing the extrudable material with a conveyor; conveying the extrudable material through the passage to subject the extrudable material to shear forces to shape the extrudable material, cooling the extrudable material within the passage, and discharging the extrudable material from the extrusion at the outlet side of the passage as the extruded product.

[0120] In certain embodiments, the extrudable material is heated in the extruder to a temperature between about 115 °C and about 170 °C. In certain embodiments, the extrudable material is heated in the extruder to a temperature between about 120 °C and 160 °C. The temperature could be readily adjusted by the person skilled in the art based on the desired characteristics of the extruded product.

[0121] In certain embodiments, the drawing step comprises drawing the extrudable material directly or indirectly from the extruder, and / or from a distributor that receives extrudable material from the extruder.

[0122] The extrudable material may comprise one or more of: a protein, a carbohydrate, a starch, a gum, a fibrous material, a gelling agent; and / or is a protein composition, a carbohydrate composition, or a starch composition. In certain embodiments, the extrudable material is a protein composition. In certain embodiments, the protein composition is in the form of a protein paste. In certain embodiments, the protein composition comprises fibrous protein. In certain embodiments, the protein composition has a protein content of from about 5 wt % up to about 100 wt% based on dry weight of the protein composition. In certain embodiments, the protein composition has a protein content of from about 50 wt % up to about 100 wt% based on dry weight of the protein composition, or about 60 wt % up to about 100 wt% based on dry weight of the protein composition, about 70 wt % up to about 100 wt% based on dry weight of the protein composition or about 70 wt % up to about 80 wt% based on dry weight of the protein composition. In certain embodiments, the protein composition has an initial moisture content of at least 25 wt% based on the total weight of the protein composition. In certain embodiments, the initial moisture content is about 50 wt% up to about 85 wt% based on the total weight of the protein composition, or about 60 wt% up to about 80 wt% based on the total weight of the protein composition. In certain embodiments, the initial moisture content is about 60 wt% up to about 70 wt% based on the total weight of the protein composition. As would be understood by the person skilled in the art, the above references to “protein composition” include other extrudable material disclosed herein.

[0123] In certain embodiments, the extrudable material is cooled in the passage to a temperature of 100 °C or less at the outlet side. In certain embodiments, the extrudable material is cooled in the passage to a temperature of about 85 °C to about 55 °C at the outlet side. In certain embodiments, theextrudable material is cooled in the passage to a temperature of about 80 °C to about 60 °C at the outlet side.

[0124] In other embodiments, the extrudable material is a polymer (eg nylon, polycarbonate, acrylonitrile butadiene styrene), polymer blend (eg acrylonitrile butadiene styrene and polycarbonate, nylon and polybutylene terephthalate, polypropylene and polyethylene, polyamide and polyethylene, or polycarbonate and polybutylene terephthalate), thermoplastic elastomer (eg styrene block copolymers, polyether block amides, polyolefin elastomers, thermoplastic polyurethane, chlorinated polyethylene), fibre reinforced composite (eg glass, carbon fiber or aramid fibre reinforced polypropylene or nylon), or non-woven fabric. In these embodiments, the extrudable material is cooled in the passage to a temperature below a melting point of the extrudable material, for example, between about 1 °C and about 100 °C below the melting point, or about 1 °C and 50 °C below the melting point. As the person skilled in the art would appreciate, this allows the extruded material to cool down and solidify. The person skilled in the art could determine an appropriate temperature based on the extrudable material and the desired properties, eg, a higher cooling die temperature increases crystallinity, reduces flexibility, increases strength and hardness, and improves dimensional stability, whereas a lower cooling die temperature decreases crystallinity, increases flexibility, reduces strength and hardness, and increases shrinkage and warping.

[0125] Yet another aspect of an embodiment of the present disclosure provides a method of extruding an extrudable material, the method comprising drawing the extrudable material with a conveyor, conveying the extrudable material through a passage formed between an exterior surface of the conveyor and a co-operative surface spaced over at least a portion of the exterior surface, and regulating the exterior surface of the conveyor and / or the co-operative surface to cool the extrudable material in the passage.

[0126] In certain embodiments, the co-operative surface is a stationary surface. In alternative embodiments, the co-operative surface is a non-stationary surface. That is, in one or more forms, the cooperative surface is a conveyor surface of a second conveyor. In certain embodiments, a conveyor speed of the exterior surface and the co-operative surface is each independently configured. In certain embodiments, the conveyor speed of the co-operative surface is determined by a passive drag of the extrudable material.

[0127] In certain embodiments, the extrudable material is drawn directly or indirectly from an extruder and / or from a distributor that receives extrudable material from an extruder.

[0128] The extrudable material may comprise one or more of: a protein, a carbohydrate, a starch, a gum, a fibrous material, a gelling agent; and / or is a protein composition, a carbohydratecomposition, or a starch composition. In certain embodiments, the extrudable material is a protein composition. In certain embodiments, the protein composition is in the form of a protein paste. In certain embodiments, the protein composition comprises fibrous protein. In certain embodiments, the protein composition has a protein content of from about 5 wt % up to about 100 wt% based on dry weight of the protein composition. In certain embodiments, the protein composition has a protein content of from about 50 wt % up to about 100 wt% based on dry weight of the protein composition, or about 60 wt % up to about 100 wt% based on dry weight of the protein composition, about 70 wt % up to about 100 wt% based on dry weight of the protein composition or about 70 wt % up to about 80 wt% based on dry weight of the protein composition. In certain embodiments, the protein composition has an initial moisture content of at least 25 wt% based on the total weight of the protein composition. In certain embodiments, the initial moisture content is about 50 wt% up to about 85 wt% based on the total weight of the protein composition, or about 60 wt% up to about 80 wt% based on the total weight of the protein composition. In certain embodiments, the initial moisture content is about 60 wt% up to about 70 wt% based on the total weight of the protein composition. As would be understood by the person skilled in the art, the above references to “protein composition” include other extrudable material disclosed herein.

[0129] In certain embodiments, the conveyor is a rotatable drum configured to rotate about a longitudinal axis thereof. In certain embodiments, the method comprises rotating the extrudable material through the passage along an arc about the longitudinal axis to subject the extrudable material to shear forces to shape the extrudable material.

[0130] In certain embodiments, the conveyor is a conveying belt and the co-operative surface is a surface of a second conveying belt.

[0131] In certain embodiments, the step of conveying the extrudable material through the passage further comprises subjecting the extrudable material to shear forces. In certain embodiments, the shear forces induce shear alignment of fibrous components within the extrudable material. In certain embodiments, the method comprises operating the first and second conveying belts at different speeds to impart shear forces on the extrudable material as it is conveyed through the passage. In certain embodiments, the method comprises operating the first and second conveying belts at the same speed. In certain embodiments, a conveyor speed of the first conveying belt is independently controlled. In certain embodiments, a conveyor speed of the second conveying belt is independently controlled. The different speeds may be determined by driving one conveying belt and allowing the other conveyor to “idle”. As such, the speed of the idling conveyor is determined by the adhesion of the protein paste to the respective receiving surfaces and the tensile force applied to the protein paste (eg the second conveying belt is passively dragged by the protein paste).

[0132] In certain embodiments, the extrudable material is cooled during the step of distributing the extrudable material. The cooling using the distributor may be as described elsewhere herein.

[0133] In certain embodiments, prior to the step of drawing the extrudable material from the extruder, the method further comprises distributing the extrudable material uniformly or non-uniformly over a width of the conveyor, e.g. in the form of one or more streams, which are created by mechanical means or by injecting different materials, such as fat or gels. The distributing of the extrudable material may be as described elsewhere herein, for example, with reference to the first or second aspect.

[0134] In certain embodiments, the method further comprises using a static mixer to mix one or more additives into the extrudable material prior to distributing the protein composition onto the conveyor. Suitable additives, particularly in the context of the extrudable material being an edible material, include fat, flavouring agents, nutrients, preservatives, texture modifying agents, and combinations thereof.

[0135] In certain embodiments, the operating the exterior surface of the conveyor and / or the cooperative surface to cool the extrudable material in the passage comprises adjusting or maintaining a temperature of the exterior surface of the conveyor and / or the co-operative surface to cool the extrudable material to a temperature of 100 °C or less at an outlet side, or 85 °C to 55 °C at the outlet side or to about 80 °C to about 60 °C at the outlet side. As such, in certain embodiments, the extrudable material is cooled in the passage to a temperature of 100 °C or less at the outlet side. In certain embodiments, the extrudable material is cooled in the passage to a temperature of about 85 °C to about 55 °C at the outlet side. In certain embodiments, the extrudable material is cooled in the passage to a temperature of about 80 °C to about 60 °C at the outlet side.

[0136] In certain embodiments, the extruded material has a protein content of from about 5 wt % up to about 100 wt% based on dry weight of the extruded material. In certain embodiments, the extruded material has a protein content of from about 50 wt % up to about 100 wt% based on dry weight of the extruded material, or about 60 wt % up to about 100 wt% based on dry weight of the extruded material, about 70 wt % up to about 100 wt% based on dry weight of the extruded material or about 70 wt % up to about 80 wt% based on dry weight of the extruded material.

[0137] In certain embodiments, the extruded material comprises one or more of: a protein, a carbohydrate, a starch, a gum, a fibrous material, a gelling agent; and / or is a protein composition, a carbohydrate composition, or a starch composition. In certain embodiments, the extruded material is a protein composition. In certain embodiments, the extruded material comprises a fibrous protein. In certain embodiments, the extruded material has a fibrous texture. In certain embodiments, the extrudedmaterial is a meat substitute or meat alternative, snack, breakfast cereal, energy bar, pet food, dietary supplement or functional food.

[0138] The understanding of terms and features used herein from any given embodiment or aspect may be used to inform the understanding of the same or equivalent terms and features in other embodiments and aspects.EXAMPLESExample 1

[0139] Lab-scale extrusion trials were carried out using different prototypes of the cooling die. A number of different plant proteins were tried and proved successful. They were soy protein, chickpea protein, mung bean protein and lupin protein.

[0140] Materials

[0141] Soy protein isolate: The soy protein isolate was purchased from ADM (PROFAM 975, Isolated soy protein 266-974, Decatur, IL 62525, USA). The soy protein isolate had a protein content of >90% and was highly soluble, functional and dispersible. It is recommended to be used for processed meats, emulsified meats, sausage-type meats and extrusion by the supplier. Soy protein concentrate: the soy protein concentrate was ADM Arcon SM (ADM 266405). The soy protein concentrate had a protein content of 70% on a moisture-free basis and a fiber content of 20%. The ADM Arcon SM has a very low flavour profile, high protein solubility and superior fat emulsifiability and is suitable for emulsified and injection meat systems based on the supplier’s information. Soy flour: The soy flour (defatted) was also sourced from ADM. Soy flour had protein content of around 50%, carbohydrate around 36% and fiber around 15%. Mung bean protein: The mung bean protein was from Green Boy (GMSCP-80B-2301242) and had a protein content of >80%. Lupin protein isolate: The lupin protein isolate was prepared inhouse. The powder had a protein content of around 79%. Lupin flour: Lupin flour was ground from dehulled lupin seeds with a protein content of 40%, fibre of 31% and carbohydrate of 43%. Chickpea protein: The chickpea protein isolate, chickpea protein concentrate and chickpea flour were purchased from Yantai T. Full Biotech Co. Ltd. Green Boy Group B.V. (BP 230089). The chickpea protein isolate had a protein content of 80%. The chickpea flour had a protein content of 24%, fibre of 7.6% and carbohydrate of 60%. The chickpea protein concentrate had a protein content of 54.4%, carbohydrate of 32.9%, and fibre of 29.6%.

[0142] Methods

[0143] Lab extruder: The lab scale extrusion trials were conducted using a twin screw extruder according to the following general method. Specific conditions are noted further below. The twin screw extruder was equipped with 32 mm diameter co-rotating twin screws with L / D of 22 (The screws were configured with 295 mm forward conveying section (consisted of 4x30 mm pitch and 7x25 mm pitch forward conveying screws), 74 mm mixing section (consisted of 4x 12 mm pitch forward conveying screws with 4x5 mm notches and 3x8.8 mm kneading blocks), 160 mm forward conveying section (consisted of 8x20 mm pitch forward conveying screws), 53 mm mixing section (consisted of 6x8.8 mm pitch kneading blocks), and 90 mm metering section (consisted of 6x 15 mm pitch forward conveying screws elements)) running at 400 rpm (range 400-5 OOrpm), and four temperature control barrels which were set at 20, 50 150 and 160 °C. Water was fed using a piston pump running at full speed to deliver 9.2 L / h of water. Dry powder was fed by a volumetric screw feeder and the output was adjusted to give an overall moisture content of the melt of 50-70% MC.

[0144] Cooling die: Various embodiments of the cooling die were developed. An embodiment of the cooling die comprised a temperature-regulated outer surface (ie the stationary co-operating surface) via a water jacket. A further embodiment comprised a streamlined melt distributor immediately upstream of the cooling die. A further embodiment comprised a streamlined melt distributor with a restriction to reduce pressure and throughput. A further embodiment comprised a belt-driven die, with a driven lower belt and an undriven upper belt. The adhesion of the melt between the belts determined the speed of the upper belt. A further embodiment comprised an arrangement to co-extrude the extrudate with a plastic film to provide a packaged extrudate. A carrier introduced the film to the upper surface of the melt as it entered the passage between the upper and lower belts, such that the extrudate was covered in the plastic film.

[0145] Experimental conditions

[0146] An embodiment of the cooling die was developed with a temperature-regulated outer surface (ie stationary co-operating surface) via a water jacket.

[0147] Trial 1: Material: Soy protein isolate + 10% water added to improve the feed flowability. Extrusion condition: T: 20, 50, 150, 160C; Dry feed: 6.3kg / h. Water feed: 9.2kg / h. Screw speed ~400rpm. Estimated -65% overall moisture content. Pressure: ~6bar.

[0148] Trial 2: Material: Arcon SM; Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 6.3kg / h (10% water added to powder in advance). Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated -65% moisture content. Pressure: 3bar (no oil); 1.5-2bar (after 5% oil added to the powder).

[0149] Trial 3: Material: Mung bean protein (80% protein). Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 6.3kg / h (10% water added to powder in advance). Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated -65% moisture content.

[0150] Trial 4: Lupin protein isolate. Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 6.3kg / h (10% water added to powder in advance). Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated -65% moisture content.

[0151] Trial 5: Soy flour. Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 6.3kg / h (10% water added to powder in advance). Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated -65% moisture content.

[0152] Trial 6: Lupin flour. Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 6.3kg / h (10% water added to powder in advance). Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated -65% moisture content.

[0153] Trial 7: Lupin protein isolate + lupin flour. Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 6.3kg / h (10% water added to powder in advance). Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated -65% moisture content.

[0154] Trial 8: Chickpea flour. Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 6.3kg / h (10% water added to powder in advance). Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated -65% moisture content.

[0155] Trial 9: Chickpea protein concentrate. Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 6.3kg / h (10% water added to powder in advance). Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated -65% moisture content.

[0156] Trial 10: Chickpea protein isolate. Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 6.3kg / h (10% water added to powder in advance). Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated -65% moisture content.

[0157] Trial 11: Using embodiment of a streamlined melt distributor immediately upstream of the cooling die. Materials: Soy protein concentrate (Arcon SM). Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 4-6 kg / h. Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated moisture content: 60% - 70%.

[0158] Trial 12: Using embodiment of a streamlined melt distributor with a restriction to reduce pressure and throughput. Materials: Soy protein concentrate (Arcon SM). Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 4-6 kg / h. Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated moisture content: 60% - 70%.

[0159] Trial 13: Using embodiment of belt-driven die, with a driven lower belt and an undriven upper belt. Materials: Soy protein concentrate (Arcon SM). Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 4-6 kg / h. Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated moisture content: 60% - 70%.

[0160] Trial 14: Using embodiment comprising an arrangement to co-extrude the extrudate with a plastic film to provide a packaged extrudate. Materials: Soy protein concentrate (Arcon SM). Extrusion condition: T: 20, 50, 150, 160°C. Dry Feed: 4-6 kg / h. Screw Speed: ~400rpm. Water: 9.2kg / h. Estimated moisture content: 60% - 70%.

[0161] Results

[0162] Trial 1 observations: The extrudates had a chewy or rubbery texture.

[0163] Trial 2 observations: The extrudates comprised a loose fibrous chicken breast-like texture. The die pressure was around 3 bar without oil addition and 1.5-2 bar with 5% oil added to the powder.

[0164] Trial 3 observations: The extrudates formed a good fibrous structure.

[0165] Trial 4 observations: The extrudates formed a less fibrous structure than trial 3.

[0166] Trial 5: observations: The extrudate of soy flour was non-fibrous.

[0167] Trial 6 observations: Extrudate of lupin flour was non-fibrous.

[0168] Trial 7 observations: The texture of the extrudate produced using a blend of lupin protein isolate and lupin flour improved slightly over lupin flour but still non-fibrous.

[0169] Trial 8 observations: A non-fibrous structured extrudate was produced using chickpea flour.

[0170] Trial 9 observations: The extrudate produced using chickpea protein concentrate was non-fibrous.

[0171] Trial 10 observations: Some fibrous structure was produced in the chickpea protein isolate extrudate.

[0172] We observed from trials 1-10 that the surface of the paste passage of the distributor was not smooth which caused an un-stable flow of the melt and occasional pressure build-up within the melt distributor and sudden pressure release. A further embodiment of the distributor was developed, which was designed to streamline the melt passage and control the pressure release. This was used in trial 11, in which we observed smooth and stable delivery of the melt and no pressure built up in the melt distributor and pressure surging. .

[0173] A further embodiment of the streamlined melt distributor with a restriction was then developed to create a sudden pressure drop. The restriction may serve multiple purposes, such as texture modification (eg, balloon-puffing of the melt to create a porous structure through high pressure / temperature water flash off). This was used in trial 12, in which we observed smooth and stable delivery of the melt with steam bubbles led to the generation of porous extrudates.

[0174] A further embodiment comprised a belt-driven die, with a driven lower belt and an undriven upper belt. The adhesion of the melt between the belts determined the speed of the upper belt. As such, the upper belt was passively dragged by the melt. This was used in trial 13, in which we observed fibrous textured extrudates smoothly coming through the belt-driven die.

[0175] A further embodiment comprised an arrangement to co-extrude the extrudate with a plastic film to provide a packaged extrudate. This was used in trial 13, in which we observed that the extrudate exiting the die was sandwiched between the film and the lower belt. The extrudate maintained the expected fibrous texture.Example 2

[0176] A pilot scale extrusion trial was carried out using a drum embodiment of the cooling die with temperature control. The aim of the pilot scale trials was to: 1) Test how the cooling die could cope with the high throughput of the pilot scale extruder; 2) Test whether the cooling die was able to make extrudates with a range of textures e.g. from “soft” to “hard”; 3) Test whether the cooling die could generate a “porous / loose” textured meat analogue; and 4) Identify any advantages of the cooling die relative to a conventional cooling die.

[0177] Methods

[0178] Materials: Soy protein concentrate (ADM 266405 Arcon SM, ADM)

[0179] The pilot scale extrusion trials were conducted in a Clextral EV32 twin screw extruder according to the following general method. There are six barrels in the Clextral extruder. The barrel temperature can be set and controlled. The conditions included: T(l): 30, 50, 80, 110, 140, 120°C; T(2): 30, 50, 80, 110, 120, 105°C; T(3): 30, 50, 80, 115, 130, 105°C; T(4): 30, 50, 80, 110(115), 130, 110°C; T(5): 40, 60, 100, 130, 130, 110°C; or T(6): 50, 80, 100, 130, 120, 95°C. For each extrusion run, the six barrels were running at the set temperature, eg. Extrusion condition 1 - T(l): barrel 1 was set at 30°C, barrel 2 set at 50°C, barrel 3 at 80°C, barrel 4 at 110°C, barrel 5 at 140°C and barrel 6 at 120°C. T(2) - T(6) are different temperature settings. The screw speed was 400, 500 or 600 rpm. Water feed: 10 - 50 kg / h. Dry powder feed: 10 to 30 kg / h. Cooling die temperature: 60 °C & 80 °C. Specific conditions are noted in Table 1 below.TABLE 1: EXTRUSION CONDITIONS

[0180] Results

[0181] Sample 1 - 6 (70%MC): Good light fibrous structure formed.

[0182] Sample 7 - 9 (65%MC): Reducing the moisture content made extrudates harder and darker. But still formed a good light fibrous structure.

[0183] Sample 10-14 (63%MC): Further reducing the moisture content to 63% made extrudates harder and darker. But still formed a good darker fibrous structure.

[0184] Sample 15-19 (63%MC): Increasing the cooling die temperature from 60°C to 70°C, made the extrudate more fibrous.

[0185] Sample 20-24 (63%MC): Reducing the extruder temperature to 120°C and the exit temperature to close to 100°C reduced the pressure surging and steam flash-off. The extrudate was less fibrous.

[0186] Sample 25-27 (70%MC): At this low temperature, the extrudate turned “mushy” and less fibrous when MC increased to 70%.

[0187] Sample 28-31 (70%MC): Increasing the extrusion temperature. T: 30, 50, 80, 115, 130, 105 °C. The extrudate was softer and fibrous, forming a balanced fibrous texture with tenderness.

[0188] Sample 32-34 (63%MC): At the same temperature but reducing the MC% the hardness of the extrudate increased.

[0189] Sample 35 (62.7% MC): Increasing the Screw Speed (SS) from 400rpm to 500 rpm made the extrudate darker.

[0190] Sample 36 (70% MC): Increasing the moisture content made the extrudate lighter. The fibrous structure was maintained.

[0191] Sample 37 (63%MC): A porous & fibrous structure was formed by the steam flash-off, but the pressure was surging. It was a challenge to overcome the pressure surging with non-streamlined melt distributors. The pressure surging disappeared after the modification by streamlining the melt distributor.

[0192] The results are summarised in Table 2 (below), which show the cooling die was able to operate at a wide range of moisture content (MC%) and generate extrudate with “soft” to “hard”, and “light” to “dark” fibrous textures. As such, the cooling die was able to generate different meat analogues. A “Porous / loose” textured meat analogue was able to be generated through steam flash-off.TABLE 2: SUMMARY OF PILOT SCALE EXTRUSION RESULTSExample 3

[0193] A pilot scale trial was carried out to compare a conventional cooling die with a drum embodiment of the cooling die with temperature control.

[0194] Methods

[0195] Extrusion was performed using the conditions for Sample 1-6 from Example 2. The cooling die was set to 60 or 80 °C. The distributor feeding the melt to the cooling die had an opening of 10 mm x 20 mm. The conventional cooling die had a length of 450 mm and an opening of 10 mm x 20 mm.

[0196] Results

[0197] The maximum throughput of the conventional cooling die was 20 kg / h (melt) with the die pressure at 20 bar (measured at the end of extruder screw and at the start of the cooling die). In contrast, with the drum embodiment of the cooling die, for the same throughput of 20 kg / h (melt), the die pressure was only 5 bar. If the die pressure was increased to 11 bar, then the throughput of the drum embodiment of the cooling die increased to 80kg / h (melt). As such, the drum embodiment of the cooling die of the disclosure had 3-4 times the throughput than that of conventional cooling die with similar sized opening.

[0198] Notably, the operation window (the range of throughput and MC% range) of the conventional cooling die was much narrower than the new cooling die with the similar sized opening. Textural sensory evaluation was conducted to compare the textural attributes (e.g. “chewiness”, “hardness”, “juiciness” and “tenderness”) of the extrudates made using the new cooling die with that made using conventional cooling die and the true chicken meat. The results in Figure 7 showed the extrudates made using a drum embodiment of the cooling die were significantly less “chewy” (Figure 7A), less “hard” (Figure 7C) than those made using the conventional cooling die and true chicken meat. The extrudates made using a drum embodiment of the cooling die were also more “tender” (Figure 7D) and “juicy” (Figure 7B) than those made using the conventional die and had similar “tenderness” (Figure 7D) and “juiciness” (Figure 7B) to true chicken meat.Example 4

[0199] A pilot scale trial was carried out to with an embodiment of the drum cooling die with a partition to restrict the width of the passage between the rotating outer surface of the drum and the stationary co-operating surface.

[0200] Methods

[0201] Extrusion was performed using the conditions for Example 2. The cooling die was set to 80 °C. The distributor feeding the melt to the cooling die had an opening of 5 mm x 35 mm. The height and width of the passage defined by the partition was 10 mm and 40 mm respectively.

[0202] Results

[0203] The partition successfully restricted the width of the passage and the resulting extrudate. The extrudate had the expected fibrous texture and the range of hardness as observed in example 2.

[0204] The position of the partition may be adjusted according to the width of the distributor to adjust the width of the extrudate.Example 5

[0205] A pilot scale extrusion trial was carried out using a belt-driven embodiment of the cooling die with temperature control.

[0206] Methods

[0207] Extrusion was performed using the conditions for Example 2.

[0208] The belt-driven cooling die comprised a driven lower belt and an undriven upper belt. The adhesion of the melt between the belts determined the speed of the upper belt. As such, the upper belt was passively dragged by the melt.

[0209] Results

[0210] The belt-driven cooling die was easy to handle the maximum throughput of the Clextral extruder. The extrudate had the expected fibrous structure and the range of hardness as observed in example 2.

[0211] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that such prior art forms part of the common general knowledge.

[0212] It will be understood that the terms “comprise” and “include” and any of their derivatives (e.g. comprises, comprising, includes, including) as used in this specification, and the claims that follow, is to be taken to be inclusive of features to which the term refers, and is not meant to exclude the presence of any additional features unless otherwise stated or implied.

[0213] In some cases, a single embodiment may, for succinctness and / or to assist in understanding the scope of the disclosure, combine multiple features. It is to be understood that in such a case, these multiple features may be provided separately (in separate embodiments), or in any other suitable combination. Alternatively, where separate features are described in separate embodiments, these separate features may be combined into a single embodiment unless otherwise stated or implied. This also applies to the claims which can be recombined in any combination. That is a claim may be amended to include a feature defined in any other claim. Further a phrase referring to “at least one of’ a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover: a, b, c, a-b, a-c, b-c, and a-b-c.

[0214] It will be appreciated by those skilled in the art that the disclosure is not restricted in its use to the particular application or applications described. Neither is the present disclosure restricted in its preferred embodiment with regard to the particular elements and / or features described or depicted herein. It will be appreciated that the disclosure is not limited to the embodiment or embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope as set forth and defined by the following claims.

Claims

CLAIMS1. An extrusion die comprising: a conveyor having a receiving surface for receiving and drawing an extrudable material; a co-operative surface spaced over at least a portion of the receiving surface of the conveyor to define a passage between the receiving surface and the co-operative surface; the passage having an inlet side and an outlet side, whereby on operation of the conveyor, the receiving surface of the conveyor within the passage moves from the inlet side to the outlet side of the passage.

2. The extrusion die of claim 1, wherein the co-operative surface is spaced over the receiving surface at a fixed distance such that the passage has a fixed height from the inlet side to the outlet side.

3. The extrusion die of any one of the preceding claims, wherein the extrusion die is configured to receive a web of the extrudable material from at least one extruder over the receiving surface at the inlet side of the passage.

4. The extrusion die of any one of the preceding claims, wherein, in use, the movement of the receiving surface draws the extrudable material into and through the passage of the conveyor, and wherein the receiving surface and / or the co-operative surface are configured to cool the extrudable material in the passage.

5. The extrusion die of claim 4, wherein the receiving surface of the conveyor and / or the cooperative surface are configured to cool the extrudable material to a temperature of 100 °C or less at the outlet side.

6. The extrusion die of claim 5, wherein the receiving surface of the conveyor and / or the cooperative surface are configured to cool the extrudable material to a temperature of about 85 °C to about 55 °C at the outlet side.

7. The extrusion die of any one of the preceding claims, wherein the conveyor is a rotatable drum configured to rotate about a longitudinal axis thereof, and the receiving surface is an exterior surface of the rotatable drum.

8. The extrusion die of claim 7, wherein the receiving surface has a width that extends in the direction of the longitudinal axis, and the co-operative surface extends over at least the width of the receiving surface.

9. The extrusion die of claim 7 or 8, wherein the extrusion die further comprises a stationary outer drum segment that encloses at least a portion of the rotating drum, and the co-operative surface is an internal stationary surface of the stationary outer drum.

10. The extrusion die of claim 9, wherein the stationary outer drum segment is in the form of an arc with arc length of from about 90 degrees up to about 270 degrees.

11. The extrusion die of any one of the preceding claims, wherein the conveyor is a conveying belt, and the receiving surface is a surface of the conveying belt.

12. The extrusion die of claim 11, wherein the extrusion die further comprises a second conveying belt, and the co-operative surface is a surface of the second conveying belt.

13. The extrusion die of claim 12, wherein the first and second conveying belts are configured to draw the extrudable material at different speeds.

14. The extrusion die of any one of the preceding claims, further comprising a partition between the receiving surface and the co-operative surface to limit a width of the passage.

15. An extrusion system comprising: the extrusion die of any one of the preceding claims; the extruder; and a distributor located downstream of the extruder and upstream of the extrusion die, the distributor configured to receive the extrudable material from the extruder and distribute the extrudable material in the form of a uniform or non-uniform stream to the receiving surface of the conveyor.

16. The system of claim 15, wherein the distributor comprises a structure to separate the stream into a plurality of sub-streams.

17. The system of claim 15 or 16, wherein the distributor further comprises a static mixer, the static mixer configured to introduce one or more additives into the extrudable material.

18. The system of any one of claims 15 to 17, wherein the distributor comprises a restriction to reduce a pressure of the extrudable material downstream of the restriction.

19. The system of any one of claims 15 to 18, wherein the system further comprises first and second carriers to introduce a film to the external surfaces of the extrudable material.

20. A method of forming an extruded product using the extrusion die of any one of the preceding claims, the method comprising: drawing the extrudable material with the conveyor; conveying the extrudable material through the passage to subject the extrudable material to shear forces to shape the extrudable material; cooling the extrudable material within the passage; and discharging the extrudable material from the extrusion at the outlet side of the passage as the extruded product.

21. The method of claim 20, wherein the extrudable material is a protein composition.

22. A method of extruding an extrudable material composition, the method comprising: drawing the extrudable material with a conveyor; conveying the extrudable material through a passage formed between an exterior surface of the conveyor and a co-operative surface spaced over at least a portion of the exterior surface; operating the exterior surface of the conveyor and / or the co-operative surface to cool the extrudable material in the passage.

23. The method of claim 22, wherein the extrudable material comprises one or more of: a protein, a carbohydrate, a starch, a gum, a fibrous material, a gelling agent; and / or is a protein composition, a carbohydrate composition, or a starch composition.

24. The method of claim 22 or 23, wherein the extrudable material is a protein composition: having a protein content of from about 5 wt % up to about 100 wt% based on dry weight of the protein composition and / or an initial moisture content of at least 25 wt% based on the total weight of the protein composition.

25. The method of claim 24, wherein the initial moisture content is 50-75 wt% based on the total weight of the protein composition.

26. The method of claim 24, wherein the initial moisture content is 60-70 wt% based on the total weight of the protein composition.

27. The method of any one of claims 22 to 26, wherein the extrudable material is cooled to a temperature of 100 °C or less.

28. The method of claim 27, wherein the extrudable material is cooled to a temperature of 85 °C to 55 °C.

29. The method of any one of claims 22 to 28, wherein the conveyor is a rotating drum configured to rotate about a longitudinal axis thereof.

30. The method of claim 29, wherein the method comprises rotating the extrudable material through the passage along an arc about the longitudinal axis to subject the extrudable material to shear forces to shape the extrudable material.

31. The method of any one of claims 22 to 28, wherein the conveyor is a conveying belt and the cooperative surface is a surface of a second conveying belt.

32. The method of claim 29, wherein the method comprises operating the first and second conveying belts at different speeds to impart shear forces on the extrudable material as it is conveyed through the passage.

33. An extruded material formed using the method of any one of claims 20 to 32.

34. An extruded material according to claim 33, wherein the extruded material is an extruded protein product.

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