CN110573028A

CN110573028A - Rotating head extruder, extrusion method and extruded product

Info

Publication number: CN110573028A
Application number: CN201880027928.5A
Authority: CN
Inventors: 乔治·C·莫拉莱斯-阿尔瓦雷斯; V·N·莫含·姚
Original assignee: Freito-Ray North America Co Ltd
Current assignee: Freito-Ray North America Co Ltd; Frito Lay North America Inc
Priority date: 2017-04-28
Filing date: 2018-04-26
Publication date: 2019-12-13
Also published as: EP3592156A1; WO2018200810A1; EP3592156A4; CA3059230A1; MX2019012804A

Abstract

An improved rotary head extruder incorporating an auger system including more than one auger to produce an asymmetric substantially cylindrical extruded product having a density in the range of about 3.0lbs/cu ft to about 6.0lbs/cu ft. A wide variety of fine particles (e.g., powders and dusts) can be successfully introduced into a rotary head extruder and conveyed within the rotary head extruder to a die assembly where the material is cooked to form a hard and dense extrusion die having an irregular asymmetric shape. A transition at the downstream end of the auger allows continuous uniform flow to the die assembly where cooking takes place. By using the apparatus, raw materials other than the commonly used corn flour can be produced while maintaining the desired bulk density, texture and friability of the irregularly extruded product.

Description

Rotating head extruder, extrusion method and extruded product

Cross Reference to Related Applications

This application is a continuation-in-part application of U.S. application serial No. 14/538,532, filed 11/2014, the disclosure of which is incorporated herein by reference in its entirety.

background

Technical Field

The present invention relates generally to an improved rotary head extruder for feeding feedstock that is otherwise difficult to include in certain rotary extruded collet (collet), which are known in the industry as irregular collet.

description of the related Art

During the formation of irregular collet (random collet) products, it has proven difficult to add ingredients other than substantially uniform corn flour (i.e., corn flour with similar particle sizes) or refined flour due to the limitations of rotary head extruders. Figure 1 depicts a popular corn collet, known as irregular corn collet 2, produced by a rotating head extruder. Irregular corn collet 2 includes unique twisted ("irregular") shapes and protrusions and a very desirable crispy texture that can only be produced with a rotating head extruder. The general acceptance in the industry is currently the fact that this type of extruder is not capable of handling materials like powders or non-refined particulate materials. Thus, the extruder recipe for irregular collet includes only corn grits or corn flour and water to form collet 2 in fig. 1. While some other raw materials may be added to slightly alter the direct expanded product, to date, these amounts have not been sufficient to significantly alter the variety or taste of irregular collet products. In addition, the introduction of small particulate materials (e.g., powders or dusts) into a continuous irregular extrusion line often results in plugging and production downtime. Therefore, there is a need for a rotary head extruder that can continuously process additional formulations for continuous batch production. In particular, it is particularly desirable to introduce a raw material other than corn flour into a rotary head extruder and at the same time mimic the attractive properties of irregular corn collet 2, namely taste, appearance, compactness and mouthfeel (or texture). Such non-corn irregular collet products should mimic the organoleptic properties (including mouthfeel and texture) of traditionally produced corn-based shelf-stable and ready-to-eat irregular collets.

Disclosure of Invention

an improved rotary head extruder replaces the single auger commonly used with more than one auger to provide continuous production of irregularly extruded products and achieve high throughput rates. More than one screw or auger is housed within a single barrel of a rotary head extruder. The transition downstream of the single barrel ensures that the delivery to the downstream stator is continuous and uniform, ensuring proper flow of material into the barrel of the extruder for extrusion. The stator is a stationary disc surrounding the output end of the downstream inner section of a single bowl. A rotor (or rotatable disc) is disposed downstream of the stator. The rotatable disk may include a plurality of fingers (fingers) surrounding a protruding nose cone located within a die gap between the stator and the rotor.

the use of a rotary die system of a rotary head extruder with an auger or auger system as described herein for extrusion allows for the successful introduction of feedstock compositions of various fine particle sizes and wide particle size distributions into the rotary head extruder and transport thereof within the rotary head extruder to a die assembly where the material is cooked to form a wide variety of irregularly extruded products.

the irregularly-extruded product contains, in addition to the typically-used corn meal formulation, a formulation with various raw ingredients while maintaining the desired bulk density, texture, and crispness (crunch) of the irregularly-extruded collet product made from corn alone. Other benefits and advantages of the invention will be apparent to those skilled in the art.

Drawings

The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:

Figure 1 depicts typical irregular corn fasters known in the industry.

FIG. 2 depicts a perspective view of a prior art rotary head extruder used in the production of collet.

Fig. 3A depicts a close-up view of the major working components of the rotary head extruder depicted in fig. 2.

FIG. 3B depicts a detailed cross-sectional view of the major working components of the extruder depicted in FIG. 2.

Fig. 4 depicts an exploded view of one embodiment of an improved rotary head extruder.

FIG. 5A depicts a top view of one embodiment of an assembled modified extruder.

Fig. 5B depicts a partial cross-sectional side view of an embodiment of an auger system in an improved rotary head extruder.

Fig. 6A depicts a front view of a downstream end of an auger in one embodiment described herein.

FIG. 6B depicts a perspective view of the downstream end of an embodiment of a transition piece.

Fig. 7 depicts another embodiment of the extruder described herein.

FIG. 8 depicts an irregular extrusion line incorporating one embodiment of the extruder described herein.

Detailed Description

The words and phrases used herein should be understood and interpreted to have a meaning consistent with the understanding of those words and phrases by those skilled in the relevant art. No special definition of a term or phrase, i.e., a definition that is different from the ordinary and customary meaning as understood by those skilled in the art, is intended to be implied by consistent usage of the term or phrase herein. To the extent that a term or phrase is intended to have a special meaning, i.e., a meaning other than that understood by skilled artisans, such a special definition will be expressly set forth in the specification in a definitional manner that directly and unequivocally provides the special definition for the term or phrase. The terms "comprising," "including," "having," and variations thereof mean "including, but not limited to," unless expressly specified otherwise. The term "comprising" when used in the appended claims, original or modified form, is intended to be inclusive or open-ended and does not exclude any additional, unrecited elements, methods, steps or materials. The term "consisting of …" does not include elements, steps or materials other than those specified in the claims. As used herein, "upstream" and "downstream" refer to a position of an object relative to a position of another object with respect to a machine direction, wherein "downstream" refers to a direction of flow of food product material to be extruded through a die system described herein.

To better understand the limitations associated with a rotary head extruder in terms of the corn formulations that it typically uses, and the advantages of the improved extruder and method described herein, it is helpful to discuss a conventional rotary head extruder.

the rotary head extruder uses two discs to cook and gelatinize the corn meal. One disc is rotating and the other is stationary, creating the necessary friction to produce irregular collet. These extruders are high shear, high pressure machines that generate heat in the form of friction over a relatively short period of time. Barrel heating is not applied to a rotating head extruder because the energy used to cook the extrudate is generated by viscous dissipation of mechanical energy. No water addition, heating elements or cooling elements are used to control the temperature in the rotary head extruder. In contrast, rotary head extruders use friction generated in a disc (rather than in an auger or screw zone) to cook the extrudate. There is no mixing on the auger of the rotating head extruder and there is very limited compression; in particular, it is only sufficient to convey the material in the gap region in the charging basket. Instead, the cutters are at the fingers 26 (best shown in fig. 3A) as described below. While the auger region helps to transport the material to the die assembly 10, it does not mix the material and is a poor conveyor for mixing the material and certain raw materials (which include very small raw materials such as powders or flours). Instead, rotary head extruders are limited to refined cereal flour formulations within a very narrow range of particles. Any other object will typically cause an uneven flow along the single auger, which creates a blockage in the extruder flow, resulting in failure and downtime of the extruder. Further, the maximum feed throughput capacity is limited to about 400lbs/hr (pounds per hour) to about 450 lbs/hr.

FIG. 2 shows a perspective view of a typical rotating head extruder used to produce the irregular corn collet 2 depicted in FIG. 1. The pre-wetted corn meal is gravity fed from hopper 4 and fed into extruder 6. The rotating head extruder 6 comprises two main working parts that form collet into its distorted ("irregular") asymmetric shape: a single screw or auger 8 and a rotating die assembly 10. Fig. 3A and 3B show a close-up view and a detailed side view of two main working parts 12 of the extruder 6. Fig. 3A depicts a partial cross-sectional view and a perspective view of the rotor 20. Fig. 3B depicts the mold assembly 10 in a cross-sectional view, wherein the clamp 30 shown in fig. 3A is omitted from fig. 3B for clarity. The auger 8 is housed in a cylindrical housing or bowl 14 and includes an open feed portion 16, as shown in fig. 3A, through which the corn meal passes 16. It should be noted that the open feed portion 16 is slightly rotated in fig. 3A for better describing the auger 8. In practice, the hopper feeds the open feed portion 16 from above. While the barrel 14 is shown in the drawings as being very short for clarity, it will be understood that it is presented for illustrative purposes only and that the length of the barrel is not drawn to scale. The auger 8 conveys and compresses the corn meal to supply it to the rotary die assembly 10 where it is plasticized into a fluidized state in a glass transition process as further described below.

The die assembly 10 comprises two discs of brass alloy: a stator 18 (having a fixed disk) and a rotor 20 (a rotating disk). The gelatinization of the wetted starch material takes place in a concentric chamber between the two plates 18, 20. The stator 18 is an assembly including a stator head section (stator head section)22 and a circular stationary brass plate 24, the stationary brass plate 24 serving as a mold through which a solidified melt flows. The stationary disk 24 has grooves 48, and the grooves 48 assist in the compression of the corn meal when the stator 18 is operated with the rotor 20. The rotor 20 is a rotating disk comprising fingers 26 and a nose cone 28. The nose cone 28 directs the corn meal toward the fingers 26 and helps expel the coagulated corn meal through the small gap between the rotor 18 and the stator 20. The action of the fingers 26 creates the pressure and heat necessary to achieve plasticization of the material at approximately 260 ° F to 320 ° F (127 ℃ to 160 ℃). Specifically, the fingers 26 force the corn meal back into the grooves of the stator head 24, causing friction and compression of the corn meal in the gap between the stator 18 and the rotor 20. The brass faces 32 on the rotor 20 also contribute to heat and compression. Thus, irregular extrusion may be characterized by a thermo-mechanical transformation of the feedstock caused by metal-metal interactions of the die assembly 10.

During irregular extrusion, several things occur in the die assembly 10. First, the corn meal is subjected to high shear rates and pressures, which generate most of the heat used to cook the corn. Thus, unlike other extruders, most cooking occurs in the rotating die assembly 10 of the rotating head extruder. As mentioned above, no added water or external heat is present in the extruder for temperature control. Second, the rapid pressure loss causes the superheated water in the corn mass to turn into steam, puffing the cooked corn as it exits the die assembly. Third, the flow of corn between a rotating disk 20 and a stationary disk 18 distorts the expanded corn causing portions thereof to distort and fold, thereby forming the product feature shown in FIG. 1. The irregular collet exits the rotary head extruder circumferentially outward from the gap between the stator and rotor on a radial path from the center of the finger in the general direction of the straight arrow depicted in fig. 3A. The cutter blades in the cutter assembly then sever the canyon 2 created by the expansion process of the stator-rotor interaction. This process is completely unique, providing non-systematized, irregularly shaped collet and unique texture in its brittleness, producing some homemade (homemade) effects.

Typical prior art corn meal sizes for rotary head extruders include, for example, a particle size distribution wherein no more than 2.5% of the particles may be less than 300 microns. On the other hand, the extruder described herein can successfully process any food mass having a particle size distribution comprising more than about 5% to 10% of particles smaller than 300 microns. While other extruders may provide greater flexibility in the components described herein, only a rotating head extruder may perform irregular extrusion and produce irregular collet 2 with a unique shape and a bulk density of about 3.0lbs/cu ft (pounds per cubic foot) to about 6.0lbs/cu ft, or more preferably about 4.0lbs/cu ft to about 5.25lbs/cu ft, as collet 2 exits the extruder.

Figure 4 shows an exploded view of the components of an improved rotary head extruder according to one embodiment of the present invention. The rotary head extruder includes a hopper 16, much like the hopper of the rotary head extruder of fig. 3 described above, through which hopper 16 the raw material enters the barrel 14. For example, the material may be introduced through a hopper or other hopper device. Within the barrel 14 is an auger system that includes more than one auger 42a, 42B, also depicted in fig. 5A and 5B. As best shown in fig. 5A and 5B, the transition piece 40 surrounds the ends of the augers 42a, 42B. The transition piece 40 fits compactly within the stator head 22. In one embodiment, the distance between the outer surface of the auger and the inner wall of the barrel 14 may be between about 0.1mm to about 0.150 mm. In one embodiment, the distance between the outer surface of the auger and the inner surface of the barrel, or the opening therebetween, is between about 0.1mm and about 0.25 mm. In one embodiment, the thread (flight) rising from the bottom of the auger will stop at least 0.1mm from the wall. In embodiments including two augers as shown in fig. 5A and 5B, the internal shape of the transition piece 40 provides an internal flow path 44 to the wider end. In the present embodiment, a figure-8 shape is shown at the upstream end of the internal flow path 44 (as shown in fig. 6A). An internal flow path 44 surrounds the end of each auger 42a, 42B, the internal shape having an 8-shape at its bottom or upstream end, the 8-shape diverging to a wider annular downstream end, as shown in fig. 6B. Fig. 7 is a top view of another embodiment of an extruder described herein, which includes three screws located within barrel 14.

Referring back to fig. 5A, in one embodiment, the improved rotary head extruder comprises: an auger system and a die assembly 10. The auger system includes more than one rotatable auger 42a, 42b located within a single barrel 14, and a transition piece 40 at the downstream end of the rotatable augers 42a, 42b, the transition piece having a figure-8 opening, the figure-8 opening including a funnel-shaped flow path. The die assembly 10 includes or consists of a stator 18 and a rotor 20 with a die gap between the stator 18 and the rotor 20, wherein the stator includes a stationary disk 24 surrounding the output end of the transition piece and the rotor 20 is a rotatable disk downstream of the stator. The rotatable disk includes a plurality of fingers 26 surrounding a protruding nose cone 28 of the rotatable disk located within the die gap. A single bowl 14 is provided at the end of a shaft controlled by a gear box (not shown) and is movably arranged such that the fingers 26 surround the downstream ends of the two augers 42a, 42b when the extruder is operated to perform irregular extrusion of food product material. It should be noted that one of the fingers 26 in fig. 5A is only partially shown to better depict the nose cone 28. In one embodiment, each of the fingers 26 has approximately the same length and circumferentially surrounds the nose cone and at least a portion of the downstream ends of the two augers 42a, 42 b.

In one embodiment, each of the two augers 42a, 42b is disposed equidistantly on the nose cone 28 and on opposite sides of the nose cone. Each of the augers 42a, 42b includes a generally cylindrical shank (shank) having an outer circumference providing a generally helical screw thread configuration, wherein the augers and their respective screw thread configurations are sufficiently close to intermesh. In one embodiment, the threads are equally spaced along the length of the auger and the diameter of each auger is consistent throughout its length. In one embodiment, the two augers are positioned in close proximity to each other such that the threads of one auger pass through the channel of the other auger to engage the one auger with the other auger. That is, in one embodiment, the two augers are conjugate, each having substantially the same screw thread configuration (i.e., substantially the same or consistent threads in size, number, angle, and shape). The conjugate augers as shown in fig. 5A and 5B fit compactly within a single barrel so that the extruded material passes around the outer portion of the collective auger assembly with little or no passage between the augers. In another embodiment, the augers may be nonconjugated so long as material is delivered to the die assembly to allow for a channel around each auger.

In one embodiment, fig. 5A and 5B depict the stator 18 and rotor 20 with a small die gap therebetween that exists during operation of a rotary head extruder. In one embodiment, the die gap is between about 1.25mm to about 2.54 mm. As previously described with respect to the rotary head extruders of the prior art, cooked and expanded or puffed product will exit the extruder circumferentially outward from the die gap. The cutting system then cuts the puffed product into a plurality of snack food sized portions.

Fig. 5B depicts an internal flow path 44 between an outer surface of auger 42a, 42B and a wall of bowl 14, according to one embodiment. Inner flow path 44 closely surrounds the ends of both augers 42a, 42b, forming a figure-8 opening toward bowl 14 at the most upstream end of transition piece 40 (as best shown in fig. 6). The opening remains constant for a length along the downstream end of the auger and then expands in a funnel shape widening out at the exit end of the material to be plasticized within the disc. That is, in one embodiment, the length of the internal flow path gradually widens in a funnel or conical shape at its downstream end. A single barrel 14 houses two augers 42a, 42b and extends horizontally along at least half of its connection to the transition piece 40 and into the figure-8 shape of the flow path 44. Although the transition portion 40 is depicted as a separate component in the drawings, it may also be an integral part of the stator head 22 adjacent the downstream end of the auger.

Returning to the embodiment of fig. 5A and 5B, the stator 18 includes a stator head 22 having an inner groove 46 at its outlet end. The stator grooves 46 are depicted as slightly exaggerated in length for clarity. The inner grooves are preferably disposed horizontally and circumferentially spaced around the circular opening. In addition, the inner recess 46 should be substantially aligned at its downstream end with a recess 48 of the holding disk 24, the holding disk 24 surrounding the outlet end of the stator head 22. In one embodiment, the mounting plate 24 comprises or consists of bronze. Other metals are also possible as long as friction is still generated in operation. At the upstream end, the inner groove 46 is in contact with the downstream end of the transition piece 40 and the inner flow path 44, the shape having a slope that extends outwardly to contact the inner groove 46. Thus, in one embodiment, the internal flow path 44 includes a funnel shape with a wide end facing the groove 46 of the stator 18. In one embodiment, the slope of the inner portion of the transition piece 40 begins at a location behind the auger or at the downstream tip of the auger to contact the inner groove 46 of the stator head 22. In one embodiment, the slope is less than about 75 degrees. In one embodiment, the slope is less than about 65 degrees. In one embodiment, the slope is less than about 60 degrees. The slope should generally allow for a smooth transition and continuous flow of extrudate to the die assembly. In one embodiment, the stator head 22 surrounds an inner portion 44, the inner portion 44 providing a quick transition or short-slope end portion between the two auger ends and the stator 18. As perhaps best shown in fig. 5B, the transition piece 40 includes an upstream portion having a substantially constant or equal thickness along its length. The equal thickness upstream bar (stem) portion spans at least half of the length of the transition piece 40. The downstream end of the transition piece 40 has a funnel-like shape that expands obliquely at its most downstream end to a mouth with a wider opening. The inner portion provides a smooth flow of material to the mold assembly 10 where it will ultimately be cooked and expanded. The rotor 20 has its own motor drive (not shown) to control the speed and rotation of the rotor during extrusion.

By successfully incorporating the described auger system into an extruder that is still capable of irregular extrusion processes, the transfer of fine or particulate material inside the extruder to the rotating die is improved, allowing for positive displacement. The rotating head extruder described herein improves the stability of the overall process and creates a robust irregular extrusion system that can accept a wide variety of raw material types for producing a variety of irregular fastnesses. In one embodiment, during irregular extrusion, the augers 42a, 42b may be rotated independently but in the same direction (actuated by separate power sources or drive gears) to provide a meshing effect with each other to transport material between the walls of the individual barrels and the augers. In one embodiment, the auger is connected via a gear box. As depicted in fig. 5A and 5B, in one embodiment, the augers are disposed horizontally within a single barrel, adjacent to each other and substantially parallel (i.e., in the same horizontal plane). However, in one embodiment, the augers 42a, 42b may also be arranged vertically, or one above the other. In one embodiment, the auger will rotate at a speed of about 100rpm (revolutions per minute) to about 500 rpm. In another embodiment, both augers will rotate at a speed of about 200rpm to about 350 rpm. In yet another embodiment, both augers will rotate at a speed of about 300rpm to about 320 rpm.

The auger system is self-cleaning and tightly intermeshed, transferring material by virtue of its co-rotating mechanism through a positive displacement action, which makes the process more independent of the nature and composition of the feedstock. Overcomes the transfer limitation caused by the composition of the raw material (such as fiber, oily particles, small particles or other components acting as lubricant) which is difficult to convey, and improves the conveying property. The rotary head extruder described herein does not require the addition of water, heating elements, and cooling elements. The energy used to cook the extrudate is generated by the friction of the die assembly. There are no holes or openings in the stator or rotor and the irregularities exit the rotating head extruder out in a circular direction from the gap between the stator and rotor.

The extruder described herein can successfully handle continuous irregular extrusion of different materials and different sized materials. For example, corn flours having a wide range of particle sizes have been successfully tested, including those that have previously presented challenges due to the very different particle sizes of corn flours. In one embodiment, food pieces comprising a particle size distribution of between about 200 microns to about 900 microns may be fed into the rotary head extruder of the present invention. In this embodiment, up to or about 80% by weight of the particle size distribution may include a fine particle size of about 400 microns. In other embodiments, the particles may range from about 200 microns to about 1200 microns, alternatively, about 50% of the particles may have a size distribution of up to or about 400 microns. Other examples and illustrations of raw materials that can be successfully extruded are provided below.

According to another aspect of the invention is an irregular extrusion method comprising the steps of: feeding the feedstock into a single barrel comprising more than one auger; transporting feedstock through a single barrel and a transition piece toward a die assembly, the transition piece having a flow path beginning at a downstream end of the auger and diverging to a wide output end, the die assembly including a stator, a rotatable disk downstream of the stator, and a die gap between the stator and the rotatable disk, wherein the stator includes a stationary head downstream of the auger and a stationary disk surrounding the output end of the transition piece, the wide output end of the transition piece communicating with the stationary disk.

In one embodiment, the rotatable disk includes a plurality of fingers that surround a protruding nose cone of the rotatable disk located within the die gap. In one embodiment, the feedstock passes through an inner portion before reaching the rotating die assembly.

As in the embodiment depicted in fig. 5A and 5B, the nose cone 28 of the rotor protrudes inwardly with its tip facing the stator so that the nose cone 28 is disposed within the die gap. The single barrel housing containing the auger system may be configured to establish the die gap between the stator and rotor. In some embodiments, the die gap may be about 1.35mm to about 1.8 mm. The step of positioning brings the single barrel with its auger so that the fingers of the rotatable disc surround at least a portion of the downstream end of the auger. In one embodiment, the fingers may also surround the downstream end of the auger, or in one embodiment, the fingers may be located about 2mm to about 6mm near the downstream end. The feeding step comprises a feed rate of about 200lbs/hr to about 600lbs/hr of feedstock. In one embodiment, the feeding step comprises a feed rate of about 400lbs/hr to about 550 lbs/hr. In one embodiment, the feeding step comprises a feed rate of 450lbs/hr or greater.

Feedstocks comprising from about 1.0% to about 18% moisture are typically useful in rotary head extruders as described herein to form irregularly extruded products. In one embodiment, the method may include the step of pre-wetting or pre-hydrating the raw materials for introduction into the rotary head extruder. In one embodiment, the feedstock comprises an initial moisture content of about 11% to about 12.5%. The feedstock may be pre-hydrated to a moisture content of about 14.5% to about 18% by weight. In one embodiment, the raw materials are pre-hydrated to a moisture content of about 16.9% by weight in the bucket. In one embodiment, the method may include the step of pre-mixing the ingredients, which may include mixing one type of ingredient with water or other water-wetted ingredients prior to introducing the ingredients into the modified rotary head extruder. In this way, for example, different materials may be wetted to the same approximate moisture level.

During the extrusion process, and possibly more specifically, the conveying step, the augers rotate together and intermesh (whether independent of each other) in the same direction and/or speed (whether in a clock or counter-clockwise direction). In one embodiment including two augers, a double-tooth (twin shot) gearbox may be used to rotate both augers simultaneously, or a single gearbox may be used in which one motor moves both shafts. In one embodiment, each auger may include its own gearbox for co-rotating independently of each other at the same speed. In one embodiment, the delivering step may include an auger speed of about 100rpm to 400 rpm. Typically, once the single barrel and rotor are positioned to set the gap, the die gap remains constant during extrusion, with only small adjustments, if necessary, in the range of ± 0.5 mm. The temperature of the stator head may range between about 260F to about 320F. In some embodiments, the rotor speed may be adjusted to about 250rpm to about 600 rpm.

The method further includes the step of expanding the feedstock into a food product having a bulk density of between about 3.0lbs/cu ft to 11lbs/cu ft (more preferably between about 3.0lbs/cu ft to 6.5lbs/cu ft). In one embodiment, the expanded and puffed food product has a bulk density of between about 4.5lbs/cu ft to about 5.0lbs/cu ft. The cutting step may also be used to cut the expanded and puffed food product to a desired size.

By way of example, fig. 8 depicts an irregular extrusion processing line that may incorporate a rotating head extruder as described herein. In short, as shown in fig. 8, in the first step of the irregular extrusion line, the mixer 60 adds moisture as it mixes the raw materials. The mixer may be vertical, as shown in fig. 8, or horizontal (not shown). The material is then transferred to a bucket elevator 42 which lifts the material to the hopper 64 of the rotary head extruder. Next, extrusion was performed using a rotating brass disc to form a hard, dense extruded product, as previously described. The product is then conveyed to a fines drum (finestock) 68, which drum 68 removes small fines from the product prior to dewatering. The product then passes through a vibratory feeder 70 to provide a uniform feed to a fryer 72 (e.g., a rotary fryer) that reduces moisture and adds oil to the extruded product. Next, an additional vibratory feeder 74 transfers the product to a coating drum 76 where the oil, flavoring and salt are mixed. The product may then be tumbled in a seasoning drum 57, wherein seasoning is applied to the surface of irregular collet.

It should be noted that although fig. 8 depicts a process for producing fried irregular corn collet, this illustration is not meant to limit the scope of the present embodiment. In one embodiment, the rotary head extruder described herein may be incorporated into a fried corn collet line for producing fried corn collet. In one embodiment, the rotary head extruder described herein may be incorporated into a baked corn collet line for producing baked corn collet.

Suitable feedstocks for extrusion using the rotary head extruders described herein are comprised of fine discrete particles without agglomeration. That is, the modified extruder can be successfully used with unbound, non-agglomerated particles (e.g., powder or powder). In one embodiment, the feedstock is a discrete ground or milled food product of refined particle size; optionally within the particle size distribution described above. As used herein, non-agglomerated particulate or non-agglomerated food material refers to a ground or ground individual food material that is separated from other food materials and not combined therewith to cause an increase in its size.

Extruded collet snack foods produced by the extrusion described herein include a matrix portion comprised of non-agglomerated food matter including a first food material; bulk density ranges from about 3.0lbs/cu ft to about 6.0lbs/cu ft; the water content is less than 3%. In one embodiment, the non-agglomerated food material comprises a second food material different from the first food material. In other words, the second food material comprises different nutritional components than the first food material. In one embodiment, the first food material comprises yellow corn meal or whole grain corn meal. In some embodiments, the non-agglomerated food material comprises one or more of cereal flour, corn flour, and legume flour. In one embodiment, the non-agglomerated food material comprises discrete hydrated milled or ground components including, but not limited to, flour or powder. In some embodiments, the first food material comprises corn flour and the second food material comprises any flour derived from beans or tubers. In certain embodiments, the non-agglomerated food material includes a third food material that is different in its nutritional composition from the first and second food materials. In some embodiments, a fourth food material different from the first and second food materials is present in the non-agglomerated food material of the base portion. Any number of additional food pieces in non-agglomerated form may be present within the matrix portion. The base portion of the collet may include, for example, one or more of: whole grain corn flour, rice, whole grain flour, rice peas, brown rice, wheat, whole wheat, peas, black beans, flat beans, potatoes, sorghum, millet, lentils, and other grain legumes or tubers, whether in the form of a powder, or other particulate form.

The invention will now be further illustrated with reference to the following examples, which should be construed as non-limiting. It should be appreciated by those of ordinary skill in the art that the techniques disclosed in the examples which follow represent techniques discovered by the inventor to function well in the practice of the invention, and thus constitute exemplary modes for its practice. Those of ordinary skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention.

Example 1 Whole grain blend

The whole grain corn flour and yellow corn flour are mixed to make a whole grain blend for extrusion and molding of whole grain irregular collet. A mixture containing about 55% whole grain corn meal and about 45% standard corn meal is introduced into a mixer and 4% to 7% water is added to the mixer. The mixture is mixed to wet out the whole grain mixture until it reaches a moisture content of about 15% to 18%. This particular corn meal has a particle size distribution between 100 microns and 700 microns, with up to 58% of the corn meal having a particle size of about 425 microns. The moisture content in the bucket was determined to be about 15.9%. The rotor position or gap is set at about 1.52mm and the stator head temperature is recorded at about 146 ℃. The auger speed was initially set at about 228rpm and the rotor had a rotor speed of about 500 rpm. The product rate was measured to be approximately 467 lbs/min and the resulting bulk density of the expanded puffed product was approximately 4.75lbs/cu ft.

Example 2 Rice flour blend 1

Mixing rice flour, yellow corn flour and yellow pea flour to obtain rice flour mixture for extruding and molding irregular rice flour. The mixture includes about 60% rice flour, about 30% corn flour, and about 10% yellow pea flour. The mixture was introduced into a mixer and 7% water was added. The mixture was mixed to wet the whole grain mixture until it reached a moisture content of about 17.5%. The rotor position or gap was set to about 1.60mm, the stator head temperature was recorded to about 132 ℃, the auger speed was initially set to about 275rpm, and the rotor had a rotor speed of about 530 rpm. The product rate was measured to be about 400 pounds per minute and the bulk density of the expanded puffed product subsequently obtained was about 5.5lbs/cu ft.

Example 3 Rice flour blend 2

Rice flour, yellow corn flour, and yellow pea flour are mixed to make a rice flour blend for extrusion and molding of irregular rice flour. The mixture includes about 55% rice flour, 30% whole grain corn flour, and 15% yellow pea flour. The mixture was introduced into a mixer and 7% water was added. The mixture is mixed to wet out the whole grain blend until it reaches a moisture content of about 17%. The rotor position or gap was set to about 1.60mm, the stator head temperature was recorded to about 139 ℃, the auger speed was initially set to about 275rpm, and the rotor had a rotor speed of about 530 rpm. The product rate was measured to be about 390 lbs/min and the resulting bulk density of the expanded puffed product was about 5.2lbs/cu ft.

All percentages are by weight unless otherwise disclosed. All percentages, parts and ratios used herein refer to percent, parts or ratios of the total weight unless otherwise specified. Unless specifically stated otherwise herein, the terms "a", "an" and "the" are not limited to one of the elements, but mean "at least one" unless otherwise indicated. The term "about" as used herein refers to the exact value indicated as well as values within statistical variations or measurement error.

The use of any and all examples, or exemplary language (e.g., "such as") provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. Unless defined otherwise, all technical and scientific terms and abbreviations used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

The methods illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein. In some embodiments, the methods described herein may suitably comprise or consist of the disclosed steps or features alone. In other words, the formulation can include or consist of the disclosed components only.

While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention. The inventors expect skilled practitioners to practice the variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, all modifications and equivalents of the subject matter recited in the claims appended hereto are intended to be included within the scope of the claims as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

the claims (modification according to treaty clause 19)

1. A rotating head extruder comprising:

An auger system comprising two or more rotatable augers within a single barrel, and a transition piece at a downstream end of the auger system;

A die assembly comprising a stator, a rotatable disk, and a die gap between the stator and the rotatable disk, the stator comprising a stator head located at the downstream end of the auger system, and a fixed disk surrounding an outlet end of the stator head and located downstream of the single barrel, and the rotatable disk being located downstream of the fixed disk, wherein the transition piece is located within the stator head and begins at a location behind the downstream end of the rotatable auger and diverges to a wider opening in communication with the fixed disk.

2. The rotating head extruder of claim 1, wherein the die gap is about 1.35mm to about 2.54mm during operation of the extruder.

3. The rotary head extruder of claim 1, wherein the stator head comprises an inner groove in communication with the transition piece.

(deletion)

5. The rotary head extruder of claim 1, wherein the augers rotate simultaneously.

6. The rotary head extruder of claim 1, wherein the auger rotates at a speed of about 100rpm to about 500 rpm.

7. The rotary head extruder of claim 1, wherein the auger is disposed horizontally within the single barrel.

8. An extrusion process comprising the steps of:

Feeding feedstock into a single barrel of a rotary head extruder, the single barrel comprising two or more augers located within the single barrel;

Transporting feedstock through the single barrel and through a transition piece toward a die assembly, the transition piece having a flow path beginning adjacent a downstream end of the auger and diverging to a wide output end, the die assembly including a stator, a rotatable disk downstream of the stator, and a die gap between the stator and the rotatable disk, wherein the stator includes a stationary head downstream of the auger and a stationary disk surrounding the output end of the transition piece, the wide output end of the transition piece being in communication with the stationary disk.

9. The method of claim 8, wherein the feeding step comprises a feed rate of about 200lbs/hr to about 600 lbs/hr.

10. The method of claim 8, wherein the feedstock has an in-barrel moisture content of about 14% to about 20%.

11. The method of claim 8, wherein the feedstock is comprised of fine discrete particles that are free of agglomeration.

12. The method of claim 11, wherein the feedstock comprises one or more of: whole grain corn flour, rice, whole grain flour, rice peas, brown rice, wheat, wholewheat, peas, black beans, panned beans, potatoes, and other grain legumes or tubers.

13. The method of claim 11, wherein the feedstock comprises corn meal.

14. The method of claim 8, including the step of expanding the feedstock within the mold assembly into a food product having a bulk density of 3.0 to 6.0lbs/cu ft.

15. The method of claim 8, wherein the food product has a final moisture content of less than about 3%.

16. The method of claim 8, wherein the temperature at the stator head is about 260 ° F to about 320 ° F.

17. A product made by the method of claim 8.

18. an extruded collet snack food product comprising:

A matrix portion comprised of a non-agglomerated food material, said non-agglomerated food material comprising a first food material;

A bulk density ranging from about 3.0lbs/cu ft to about 6.0lbs/cu ft; and

A moisture content of less than about 3%,

Wherein the extruded collet snack food product is manufactured by the rotating head extruder of claim 1.

19. The extruded collet snack food product of claim 18, wherein the non-agglomerated food material comprises a second food material different from the first food material.

20. The extruded collet snack food product of claim 18, wherein the first food material comprises yellow corn meal or whole grain corn meal.

21. The extruded collet snack food product of claim 19, wherein the first food material comprises yellow corn meal and the second food material comprises whole grain corn meal.

22. The extruded collet snack food product of claim 19, wherein the non-agglomerated food matter comprises a third food matter that is different from the first and second food matter.

23. the extruded collet snack food product of claim 19, wherein the non-agglomerated food matter comprises one or more of: cereal flour, corn flour and legume flour.

24. The extruded collet snack food product of claim 18, wherein the non-agglomerated food matter comprises a milled or ground component.

25. The rotary head extruder of claim 1, wherein the auger is conjugate.

Claims

1. A rotating head extruder comprising:

An auger system comprising more than one rotatable auger located within a single barrel, and a transition piece at a downstream end of the auger system;

4. The rotary head extruder of claim 1, wherein the auger system comprises more than two augers located within the single barrel located upstream of the transition piece.

8. An extrusion process comprising the steps of:

Feeding feedstock into a single barrel of a rotary head extruder, the single barrel including more than one auger located within the single barrel;

13. The method of claim 11, wherein the feedstock comprises corn meal.

17. A product made by the method of claim 8.

18. An extruded collet snack food product comprising:

A bulk density ranging from about 3.0lbs/cu ft to about 6.0lbs/cu ft; and

a moisture content of less than about 3%,