EP1551233A1

EP1551233A1 - Apparatus and method for exposing comminuted foodstuff to a processing fluid

Info

Publication number: EP1551233A1
Application number: EP03737175A
Authority: EP
Inventors: Eldon Roth
Original assignee: Freezing Machines Inc
Current assignee: Freezing Machines Inc
Priority date: 2002-06-18
Filing date: 2003-06-18
Publication date: 2005-07-13
Also published as: CA2490237A1; WO2003105598A1; CA2490237C; EP1551233A4

Abstract

A contactor apparatus (40) is adapted to expose a comminuted foodstuff (21) such as comminuted meat to a processing fluid such as gaseous or aqueous ammonia or carbon dioxide gas. The contactor apparatus (40) facilitates an even and consistent exposure to the processing fluid throughout the comminuted foodstuff as the foodstuff is pumped through a conduit. In order to produce this desired exposure to the processing fluid, the apparatus shapes the comminuted foodstuff into a relatively thin sheet or stream of material flowing through a contact passage (46). The processing fluid is then applied to this relatively thin sheet or stream of comminuted material from a processing fluid chamber (49). A fluid communication arrangement between the fluid chamber and the contact passage (46) allows the flow of processing fluid into the contact passage (46) and into contact with the sheet of foodstuff flowing through the contact passage (46).

Description

APPARATUS AND METHOD FOR EXPOSING COMMINUTED FOODSTUFF TO A PROCESSING FLUID

TECHNICAL FIELD OF THE INVENTION The invention relates to foodstuff processing and, more particularly, to an apparatus and method for exposing comminuted foodstuffs to a processing fluid such as ammonia gas or aqueous ammonia.

BACKGROUND OF THE INVENTION Certain food processing operations require adding processing fluids to a foodstuff.

U.S. Patent No. 5,871,795, for example, discloses a method using ammonia and/or carbon dioxide to modify the pH of a meat product. The treatment disclosed in U.S. Patent No. 5,871,795 has been shown to decrease pathogenic microbe content in meat products. U.S. Patent No. 6,389,838 also discloses a process in which a pH modifying material such as gaseous or aqueous ammonia is applied to meat products as part of an overall process that includes freezing and physically manipulating the pH modified meat product.

Treatment processes that expose foodstuffs to a processing fluid may require a controlled and consistent application of the processing fluid. Depending upon the treatment process, underexposure may not provide the desired results, while overexposure to the processing fluid may produce undesirable results. In the pH adjustment processes described in U.S. Patent Nos. 5,871,795 and 6,389,838 for example, portions of the meat product being treated maybe overexposed to the pH adjusting fluid while other portions of the meat product may be exposed to very little or none of the pH adjusting fluid. The overexposed portions may absorb sufficient adjusting fluid to affect the taste of the treated product and to produce a residual pH adjusting material odor. Underexposed portions of the meat product may not exhibit the desired pathogenic microbe inhibiting effect.

SUMMARY OF THE INVENTION A contactor or sparger apparatus according to the present invention is adapted to expose a comminuted foodstuff such as comminuted meat to a processing fluid such as gaseous or aqueous ammonia or carbon dioxide gas. The apparatus facilitates an even and consistent exposure to the processing fluid throughout the comminuted foodstuff as the foodstuff is pumped through a conduit, hi order to produce this desired exposure to the processing fluid, the apparatus shapes the comminuted foodstuff into a relatively thin sheet or stream of material flowing through a contact passage. The processing fluid is then applied to this relatively thin sheet or stream of comminuted material from a processing fluid chamber located adjacent to the contact passage. A fluid communication arrangement between the fluid chamber and the contact passage allows the flow of processing fluid into the contact passage and into contact with the sheet or stream of foodstuff flowing through the contact passage.

The contactor apparatus may use various structures to shape the comminuted foodstuff into the desired thin sheet of material, h one preferred form of the apparatus, the contact passage is defined between two substantially parallel and planar contact passage walls which force the comminuted foodstuff into a thin planar sheet of material as it flows through the contactor apparatus. In other embodiments of the invention, the contact passage comprises a narrow cylindrical or other appropriately shaped tube, hi this form of the invention, a number of tubes may run parallel to each other to provide the desired overall flow area.

One preferred form of the apparatus includes a contactor body having an inlet end adapted to receive comminuted foodstuff and an outlet end for passing the comminuted foodstuff on to further processing equipment after the foodstuff has been exposed to the processing fluid. The contact passage is located between the contactor body inlet end and outlet end. A portion of the contactor body inlet generally transitions down from inlet flow dimensions to the dimensions required to produce the desired thin sheet of material in the contact passage. A portion of the contactor body outlet similarly transitions back from the dimensions of the contact passage to the outlet dimensions that are not restricted by the dimensions of the desired thin sheet of material.

The method of the invention includes forming or producing the flowing sheet of comminuted foodstuff and then exposing the flowing sheet of material to the processing fluid in at least one of the major surfaces of the sheet, hi the preferred form of the invention, the transverse dimension of the flowing sheet of material is generally equal to a dimension of the foodstuff pieces making up the comminuted foodstuff. The processing fluid may enter the sheet of material through one or both of the opposing surfaces used to form the sheet. Alternatively to forming a sheet of foodstuff, the method may include forming a number of narrow streams of foodstuff. This form of the invention includes exposing the foodstuff in the narrow streams to the processing fluid through the walls of the structures forming the narrow streams. The invention is particularly suited for comminuted foodstuffs such as meat or meat products, including beef, pork, lamb, and other red meats. The comminuted foodstuff may also include or be made up of poultry or sea foods. Comminuted foodstuffs that may be treated according to the present method may also include various additives or fillers. As used in this disclosure and the following claims, a "coimriinuted" material comprises generally a material that has been cut into relatively smaller pieces from one or more relatively larger pieces. The meat product being treated may be originally comminuted by any suitable device such as grinder or bowl chopper, or by manual trimming or cutting. Some forms of the invention may also incorporate a grinding element for comminuting the foodstuff as it enters the process fluid contacting passage or passages. A sparging device within the scope of the present invention may be configured with two or more separate fluid chambers defined in the sparger body. Each separate fluid chamber may include a separate fluid communication device with each sparger passage. The different fluid chambers may be used to add different processing fluids to the foodstuff as it flows through the sparger passages. Including multiple fluid chambers in the sparging device according to the invention allows different processing fluids to be quickly and efficiently added to the foodstuff in rapid succession.

These and other advantages and features of the invention will be apparent from the following description of the preferred embodiments, considered along with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a somewhat diagrammatic side view of a treatment system incorporating a contactor apparatus embodying the principles of the invention, partially broken away to show the interior of the contactor apparatus. Figure 2 is a view in perspective of a contactor apparatus embodying the principles of the invention.

Figure 3 is a view in section taken along line 3-3 in Figure 2. Figure 4 is an enlarged view in section showing a portion of the insert in Figure 3.

Figure 5 is a right end view of the alternate contactor apparatus shown in Figure 2.

Figure 6 is a view in section similar to Figure 3, but showing an alternate fluid communication arrangement according to the invention. Figure 7 is a right end view of a sparging screen embodying the principles of the invention.

Figure 8 is a section view taken along line 8-8 in Figure 7.

Figure 9 is a right end view of a sparging device embodying the principles of the invention having a multiple stage sparging screen. Figure 10 is a longitudinal section view taken along line 10-10 in Figure 9.

DESCRIPTION OF PREFERRED EMBODIMENTS Figure 1 illustrates one preferred form of treatment system 10 employing a contactor or sparger device 15 embodying the principles of the invention. Treatment system 10 includes an initial comminuting device 11 and a further comminuting device 12.

Also, treatment system 10 includes a metering device 14 for directing the foodstuff through contactor apparatus 15.

Both of the comminuting devices 11 and 12 in this treatment system comprise grinders such as the Model No. 1109 grinder by Weiler & Company, Inc. Grinder 11 receives relatively large pieces of foodstuff such as meat product 20 and produces an initial or original comminuted meat product 21. The grinder plate associated with grinder 11 may include openings having a maximum dimension preferably between approximately two (2) inches and three-eighths (3/8) of an inch, h a more preferred form of the system, the grinder plate openings in grinder 11 have a maximum dimension of between one-half (V.) of an inch to three-eighths (3/8) of an inch. The maximum dimension of the openings in the grinder plate generally determines the maximum dimension of the comminuted material exiting the grinder.

It will be appreciated that the original comminuted product 21 exiting grinder 11 is made up of a plurality of discrete pieces arranged together in a continuous mass. Individual pieces are represented in the drawings at reference numeral 25. Since these individual pieces are mixed together with other discrete pieces, they are not necessarily visible individually from the collective mass of material. However, the discrete pieces 25 are shown for purposes of explaining the operation of the invention. hi treatment system 10, grinder 12 receives the original comminuted meat product after the material has been exposed to a processing fluid such as gaseous or aqueous ammonia in the contactor apparatus 15. Grinder 12 further comminutes the original comminuted material and may include a grinder plate having openings smaller than the openings in the grinder plate associated with grinder 11. For example, grinder 12 may include a grinder plate having openings with a maximum dimension of no greater than three-sixteenths (3/16) of an inch and preferably about one-eighth (1/8) of an inch. Alternatively, the grinder plate associated with grinder 12 may have the same size openings as grinder 11 and still perform some comminuting, h any event, the further comminuted material 22 exits grinder 12 and is collected for packaging or for transport to further processing equipment. Figure 1 shows the further comminuted material 22 being collected in a receiving tub 23. In the treatment system 10 shown in Figure 1, metering device 14 comprises a suitable positive displacement metering device. Metering device 14 receives the comminuted foodstuff 21 in collection chute 27 and then meters the comminuted foodstuff through processing fluid contactor 15 as indicated by the flow direction shown at arrow F. Other forms of the treatment system may use other means for forcing the comminuted foodstuff into and through contactor 15. The particular metering or pumping device will include a motor for driving the device with sufficient power to force the comminuted foodstuff through contactor 15 and the conduits leading to and from the contactor.

The treatment process performed by system 10 and the operation of contactor 15 may now be described with reference to Figures 1 through 3. Referring to Figure 1, meat 20 is ground or otherwise comminuted to form the original comminuted meat product 21.

This comminuted meat product is collected in metering device chute 27 and forced by metering device 14 through processing fluid contactor 15. hi processing fluid contactor 15, at least a portion of the comminuted meat product 21 is exposed to the processing fluid such as aqueous or gaseous ammonia. The meat product passes from contactor 15 to grinder 12 where the material is preferably further comminuted. The further comminuted meat product 22 is expelled from device 12 and collected for packaging or for further processing. The foodstuffs maybe processed according to the invention in a wide temperature range. For example, meat may be maintained at a temperature above 32 °F for both the process fluid contacting step and the further comminuting step, h any event, the meat product temperature should be high enough that some liquid component remains in the meat product during the further comminuting step.

Figures 2 through 6 show one preferred type of contactor or sparger device that may be employed as the device diagrammatically shown at reference numeral 15 in Figure 1. The perspective view of Figure 2 shows the general structure of a contactor device 40 while Figures 3 and 6 show two fluid communication variations within this general structure. The end view shown in Figure 5 is substantially identical in both alternate forms of invention shown in Figures 3 and 6.

Contactor 40 includes generally a contactor body formed by two components 41 and 42 and includes a foodstuff flow passage from a first end of the contactor body to a second end. The foodstuff flow passage in this form of the invention includes a first end or inlet end portion shown generally at reference numeral 44 and a second end or outlet end portion shown generally at reference numeral 45. These end portions 44 and 45 of the foodstuff flow passage are separated by a contact passage shown generally at reference numeral 46. As shown best in Figures 3 and 6, contact passage 46 is actually formed through a separate insert mounted within the contactor body. This insert is shown at reference numeral 48 in Figure 3, and 48' in Figure 6. The fluid communication arrangement in this form of the invention is associated with this insert as will be described further below. In both alternatives of the invention shown in Figures 3 and 6, a processing fluid chamber 49 is included in the contactor body. Processing fluid chamber 49 comprises an annular area encompassing the respective insert 48 or 48', and the insert separates fluid chamber 49 from contact passage 46.

The two end components 41 and 42 are flanged together with a flange connection shown generally at reference numeral 51. The illustrated form of contactor 40 also includes a flange 52 at one end for connecting the device to a suitable conduit, and a threaded connector 53 at the opposite end for connecting the opposite end to a suitable conduit. Although flange and threaded connectors are shown in the illustrated embodiment, it will be appreciated that the invention is by no means limited to these types of connectors. Also, although the two-piece arrangement (components 41 and 42) shown in the figures is preferred for its durability, ease of construction, and ease of assembly and disassembly, the invention is not limited to this two-piece contactor body.

It will be noted particularly from the section views of Figures 3 and 6 that the first and second end portions, 44 and 45 respectively, of the foodstuff flow passage generally define flow areas. The minimum transverse dimension of each end portion flow area reduces down from a relatively large transverse dimension at the outer ends of the flow passage to a relatively smaller minimum transverse dimension in a flow area defined by contact passage 46. As shown best in the end view of Figure 6, the preferred contact passage 46 forms an elongated oval in transverse cross section. Contact passage 46 is thus defined between two narrowly spaced opposing surfaces or contact passage walls indicated by reference numerals 56 and 57. These two surfaces 56 and 57 are both generally planar and extend parallel to each other. When a comminuted foodstuff is forced to flow through the contactor 40, the foodstuff is forced into contact passage 46 where it forms a thin planar sheet of material. The sheet of material has a relatively small minimum transverse dimension, preferably on the order of a dimension of the pieces of material making up the comminuted foodstuff being treated or less. When the transverse dimension is less that the size of the pieces of material making up the comminuted foodstuff, the foodstuff pieces spread out laterally in order to travel through the contact passage.

Process fluid chamber 49 in the forms of the invention shown in Figures 2 through 6 comprises an annular area machined or otherwise formed in components 41 and 42 around the area that receives insert 48 or 48'. This annular area is shown divided by ribs 60 into separate longitudinally spaced apart chambers 61 in communication with each other through rib openings 62. Ribs 60 help support the respective insert 48 or 48' in the desired position. Processing fluid may enter chamber 61 through a processing fluid passage 64 formed in contactor body inlet component 41. Processing fluid passage 64 may also be associated with a suitable connection 65 for connecting to a processing fluid supply conduit (not shown) for supplying processing fluid to contactor 40.

The fluid communication arrangement in the fonn of the invention shown in Figure 3 includes a number of the small openings 67 drilled or otherwise formed through the material of insert 48 separating contact passage 46 and processing fluid chamber 49. These openings 67 preferably have a small transverse dimension no greater than about 0.10 inches for processing comminuted meats, and are illustrated in the enlarged section view of Figure 4. Although openings 67 may be any size that allows the desired processing fluid contact with the foodstuff, the small openings are preferred because they allow processing fluid to flow from processing fluid chamber 49 into contact passage 46 to effect the desired contact with the foodstuff, but help prevent the foodstuff from flowing from the contact passage into the processing fluid chamber. It will also be appreciated that the processing fluid pressure maintained in chamber 49 also prevents foodstuffs from inadvertently flowing through openings 67 from contact passage 46 into processing fluid chamber 49. hi the preferred form of the invention, a large number of the openings 67 are spaced apart across the entire width of each contact passage wall 56 and 57 in each chamber 61. Openings 67 are also preferably included in both lateral ends of contact passage 46.

The alternate form of the invention shown in Figure 6 employs a porous and permeable material for the insert 48' in place of the solid and machined insert 48 shown in Figures 3 and 4. This material is permeable to the processing fluid and thus allows the processing fluid to flow from processing fluid chamber 49 into contact passage 46 under a suitable driving pressure differential between the processing fluid chamber and contact passage. However, the openings that produce the desired permeability are preferably small enough to inhibit foodstuff from flowing from contact passage 46 into processing fluid chamber 49. Ceramics and sintered materials or any other suitable material having the desired permeability to the processing fluid may be used to form insert 48'. Composite inserts made up of solid material and permeable material sections may also be employed within the scope of the invention.

In both the discrete opening form of the fluid communication arrangement shown in Figures 3 and 4, and the permeable material fluid communication arrangement shown in Figure 8, the openings provide fluid communication from chamber 49 to contact passage 46. That is, the openings at least allow processing fluid to pass from chamber 49 to contact passage 46 given the appropriate pressure in chamber 49. The openings that provide the fluid communication maybe sized and shaped to inhibit flow of foodstuff from contact passage 46 to chamber 49, but it is not required. Rather, the pressure in chamber 49 may be controlled to prevent foodstuff from flowing into the openings making up the fluid communication arrangement.

Whether the sheet of material is planar as in contactor 40 or annular/cylindrical as in contactor 15, or some other shape, the thin sheet of foodstuff may be exposed to the processing fluid in an even and consistent manner. That is, the relatively thin sheet of foodstuff material maybe exposed on both sides or major surfaces to the processing fluid. Where the spacing between the opposing surfaces of the contact passage is approximately equal to a dimension of foodstuff pieces maldng up the comminuted foodstuff, applying the processing fluid to the thin sheet generally ensures that each piece of the foodstuff is directly exposed to the processing fluid. This is to be contrasted with the situation in which a processing fluid is simply injected into a foodstuff flowing through a large conduit, hi that case the processing fluid is inherently applied unevenly with some pieces directly exposed and other pieces exposed only indirectly. Figures 7 through 10 illustrate forms of the present invention which include a number of contact passages configured as passages through a sparging screen. Referring to Figure 8, a sparging screen 80 embodying the principles of the invention includes a screen body made up of a first or inlet side component 81 and a second or outlet side component 82. A number of screen passages, each shown generally by reference numeral 84, extend through the sparging screen body from a first side 87 of the screen body to a second side 88 of the screen body. As shown best in Figure 7, a number of screen passages 84 are spaced apart across the entire area of the disk-shaped screen body. The illustrated arrangement of screen passages 84 includes an outer set of passages shown generally at reference numeral 90 and an inner set of passages shown at reference numeral 91. Each set 90 and 91 is made up of a number of pairs 92 of generally radially aligned screen passages 84, with each pair at a different angular orientation about a center point 93 of the screen body.

As shown best in Figure 8, sparging screen 80 also includes a fluid chamber 95 formed within the screen body. In this form of the invention, fluid chamber 95 is defined between the opposing surfaces of first side component 81 and second side component 82. Fluid chamber 95 may be formed between the two components 81 and 82 by areas machined or otherwise formed in one or both of the opposing surfaces. Fluid chamber 95 is in fluid communication with an imier ring 97 associated with inner screen passage set 91 and an outer ring 98 associated with outer screen passage set 90. Both the inner ring 97 and outer ring 98 are connected to a feed passage 100 formed in first side component 81 and terminating at an inlet port 101 formed in the first side component. Inlet port 101 comprises a fitting for connecting with a suitable processing fluid supply conduit (not shown). The combination of feed passage 100, and inner and outer rings, 97 and 98 respectively, provide fluid communication from inlet port 101 to fluid chamber 95.

The sparging screen 80 shown in Figures 7 and 8 includes a fluid communication device associated with each screen passage 84. This fluid communication device makes up the fluid communication arrangement in this form of the invention and, as best shown in the section view of Figure 8, comprises a cylindrical sleeve 104 captured between first side component 81 and second side component 82. The sides of the respective sleeve 104 separate the area of fluid chamber 95 from the area of the respective screen passage. Thus, each sleeve 104 actually defines a central portion of the respective screen passage 84, with the remainder of the respective screen passage being defined by an opening 107 formed in first side component 81 and an opening 108 formed in second side component 82. In some forms of the invention the material making up sleeve 104 may include small openings extending transversely from the outer surface of the cylindrical shape to the inner surface. Other forms of the invention may utilize sleeves 104 made up of a porous and permeable material. In either case, the openings in each sleeve 104 provide fluid communication from fluid chamber 95 to the respective screen passage 84.

The two side components 81 and 82 of screen 80 shown in Figure 8 may be held together in any suitable fashion in a sparging device embodying the principles of the present invention. For example, the two side components 81 and 82 maybe sandwiched between flanges (not shown) in a sparging device or may otherwise be bolted together.

The illustrated disk-shaped screen 80 made up of side components 81 and 82 is especially adapted to be used as a grinder plate in a grinder device. Thus, screen 80 includes a central opening 110 for accommodating a spindle associated with the grinding device.

Referring to Figures 9 and 10 a multiple-stage sparging device 120 embodying the principles of the invention includes a sparger body or screen body 121 having multiple fluid chambers for adding different processing fluids to a foodstuff passing through sparger or screen passages 124 in the sparger body. Referring particularly to Figure 10, this form of the invention includes two different fluid chambers, a first fluid chamber indicated generally at reference numeral 127 and a second fluid chamber indicated generally at reference numeral 128. Sparger device body 121 is connected to an inlet chamber 130 through which foodstuff may be introduced to the various sparger passages 124 and forced through the passages. In the form of the invention shown in Figures 9 and 10, sparger body 121 includes an inlet side component 132, an intermediate component 133, and an outlet side component 134. Intermediate component 133 is sandwiched between inlet side component 132 and outlet side component 134. First fluid chamber 127 is defined between the facing surfaces of inlet side component 132 and intennediate component 133, while second fluid chamber

128 is defined between the facing surfaces of intennediate component 133 and outlet side component 134. Sparger screen body 121 in this form of the invention also includes a scraper plate 135 interposed between inlet side component 132 and inlet chamber 130. This scraper plate 135 provides a surface against which a scraper blade or grinder blade may work as will be described further below.

It will be appreciated especially from the section view of Figure 10 that inlet side component 132, intermediate component 133, outlet side component 134, and scraper plate 135 each include transverse openings that align to either make up part of the respective sparger passage 124 or make room for the respective sparger passage, h particular, scraper plate 135 includes transverse openings 137, inlet side component 132 includes openings

138, intermediate component 133 includes openings 139, and outlet side component 134 includes openings 140. The bulk of each sparger passage 124 in the form of the invention shown in Figures 9 and 10 is defined by a sleeve or insert 142 captured in the sparger body 121 between scraper plate 135 and outlet component 134. Each sleeve 142 fits in a recess defined by openings 138, 139, and 140.

The particular sleeve 142 shown in Figure 10 comprises a single component having a generally uniform cylindrical inner surface 143 formed through solid material sections 144, 145, and 146, and two porous and permeable material sections 147 and 148. Porous and permeable material section 147 aligns with first fluid chamber 127 while porous and permeable material section 148 aligns with second fluid chamber 128. Thus, the porous and permeable material 147 provides a fluid communication device for communicating fluid from fluid chamber 127 to sparger passage 124 and porous and permeable material 148 provides a fluid communication device for communicating fluid from second fluid chamber 128 to the sparger passage. As with the sleeve 104 shown in the embodiment of Figures 7 and 8, the fluid communication device in this multiple-stage form of the invention may alternatively include small openings drilled or otherwise formed through the sleeve material from the outside surface of the cylindrical shape to the inside surface. Each fluid chamber 127 and 128 formed in sparger body 121 may be used to add a different processing fluid to the foodstuff as the foodstuff is forced through sparger passages 124. Thus, each fluid chamber 127 and 128 is associated with a different processing fluid inlet or feed structure for feeding a desired processing fluid into the respective fluid chamber. The feed structures shown in Figure 10 include a first inlet passage 151 associated with first fluid chamber 127 and a second inlet passage 152 associated with second fluid chamber 128. First inlet passage 151 extends through inlet side component 132 from a fitting 153 formed in an exterior surface of the inlet side component to an interior surface defining a portion of first fluid chamber 127. Similarly, second inlet passage 152 extends through outlet side component 134 from an exterior fitting 154 to an interior surface defining a portion of second fluid chamber 128.

As shown in Figure 10, inlet chamber 130 is in communication with a foodstuff inlet port 156 through which foodstuff may be introduced into the inlet chamber. A pressure auger 158 may be associated with inlet chamber 130. Auger 158 is driven about an auger axis 159 by a suitable driving arrangement (not shown) to force the foodstuff from inlet chamber 130 into sparger passages 124. Also, inlet chamber 130 may house a scraper blade assembly 160 mounted at the end of auger 158 and adapted to rotate with the auger. As best shown in Figure 9, the illustrated scraper blade 160 comprises a single elongated element. Other forms of the invention may include scrapers having several radial extending blade elements. In any case, the scraper periodically passes over scraper plate openings 137 to sever material against the entrance edge of these openings. This cutting action is analogous to the cutting action at the plate of a meat grinding device. It will be noted that the orientation of scraper 160 shown in Figures 9 and 10 is such that the section view of Figure 10 coincides with the longitudinal axis of the scraper. Thus, the section view of Figure 10 shows the scraper 160 completely filling the area defined by inlet chamber 130. It will be appreciated from Figure 9 however that scraper 160 occupies only a small portion of the inlet chamber so that the foodstuff to be treated may enter chamber 130 through inlet port 156 and then flow from chamber 130 into each of the sparger passages 124 extending through sparger body 121. Although the forms of the invention shown in Figures 7 through 10 are preferred forms of the invention, those skilled in the art will appreciate that many variations in these devices are possible within the scope of the present invention as defined in the accompanying claims. For example, a sparging device embodying the principles of the invention may or may not include cutting elements for scraping an inlet surface to the sparger passages, such as the upper surface of plate 135 in Figure 10. In particular, a finely ground or otherwise comminuted foodstuff may not require any cutting action at the inlet to the sparger passages. Also, numerous different arrangements other than an auger may be used to force the foodstuff through the sparger passages, hi particular, in the arrangement shown in Figures 9 and 10, the foodstuff may be pumped into inlet chamber 130 through foodstuff inlet port 156 with sufficient force to drive the foodstuff through sparger passages 124. Those skilled in the art will appreciate that many different arrangements may be used to connect the various components of the screen body. The components may be sandwiched between flanges formed on other components, or the components may themselves include bolt holes to accommodate bolts or other connectors for connecting the components together in the positions illustrated particularly in Figures 8 and 10. Many different sealing arrangements may also be used to seal between the various facing surfaces of a screen body embodying the principles of the invention. For example, Figure 10 shows O-rings 162 providing a seal between the facing surfaces of inlet side component 132, intermediate component 133, outlet side component 134, and scraper plate 135. Figure 10 also shows O-rings 163 associated with the solid material sections of sleeves 142. These sealing arrangements are shown only for purposes of example and are not intended to limit the scope of the invention as defined in the following claims.

The sparger or screen passages 84 and 124 shown in the two illustrated embodiments of the invention are preferably relatively small in diameter. For example, each passage may have a diameter of around one-half inch or less, although larger diameters are possible within the scope of the invention. The use of relatively small diameter sparger passages facilitates better contact between the processing fluid and the foodstuff passing through the sparger passages. Also, length of the areas provided for processing fluid communication to the sparger passages may vary widely within the scope of the invention. Figure 8, for example shows a relatively short sleeve 104, while the porous and permeable sections 147 and 148 shown in Figure 10 are relatively long.

Generally, the longer the area provided for fluid communication between the respective chamber and the sparger passage, the more processing fluid that can be sparged into the foodstuff.

The form of the invention shown in Figure 10 includes openings 140 in outlet side component 134 that taper narrower toward their respective outlet end. This taper is included to provide increased resistance to the flow of foodstuff through passages 124.

The increased resistance results in higher pressures within flow passages 124. This increased pressure allows the processing fluid to be sparged into the foodstuff through chambers 127 and 128 at a higher pressure. The higher sparging pressure maybe advantageous for certain foodstuffs and certain processing fluids, hi other forms of the invention, the length and diameter of passages 124 may be such that the passages themselves provide sufficient resistance to flow to produce the desired back pressure.

The above described preferred embodiments are intended to illustrate the principles of the invention, but not to limit the scope of the invention. Various other embodiments and modifications to these preferred embodiments may be made by those skilled in the art without departing from the scope of the following claims. For example, the invention is not limited by specific materials for the various contactor components. Generally, the contactor body components may be formed from stainless steel, however, any material suitable for food handling may be used provided the material has suitable strength and other material characteristics. Porous and permeable material used in the fluid communication arrangement may comprise any suitable material. Also, the invention is not limited to a contact passage minimum transverse dimension equal to a dimension of the foodstuff pieces being treated. A single layer or line of foodstuff pieces passing through the contact passage is preferred for the reasons described above, but is not required.

Claims

CLAIMS:

1. An apparatus for exposing comminuted foodstuffs to a fluid, the apparatus including: (a) a contactor body including a foodstuff flow passage extending from a contactor body inlet end to a contactor body outlet end;

(b) a foodstuff inlet comprising a portion of the foodstuff flow passage through the contactor body, the foodstuff inlet defining an inlet flow area;

(c) a contact passage comprising a portion of the foodstuff flow passage through the contactor body, the contact passage defining a contact flow area between two substantially planar and parallel contact passage walls and having a minimum transverse dimension smaller than a minimum transverse dimension of the inlet flow area;

(d) a fluid chamber associated with the contactor body; and (e) a fluid communication arrangement providing fluid communication between the fluid chamber and the contact passage.

2. The apparatus of Claim 1 wherein the fluid communication arrangement provides fluid communication between the fluid chamber and the contact passage through both of the substantially planar contact passage walls.

3. The apparatus of Claim 1 wherein the fluid communication arrangement comprises a number of discrete openings extending from the fluid chamber to the contact passage.

The apparatus of Claim 3 wherein the discrete openings have a maximum transverse dimension large enough for enabling a fluid in the fluid chamber to flow into the contact passage to effect a desired contact with the foodstuff in the contact passage, and small enough for inhibiting the foodstuff from flowing therethrough.

5. The apparatus of Claim 1 wherein the fluid communication arrangement comprises a porous and permeable material interposed between the volume of the fluid chamber and the contact passage.

6. The apparatus of Claim 1 wherein the contact passage minimum transverse dimension is substantially equal to a dimension of the pieces of material making up the comminuted foodstuff.

7. An apparatus for exposing comminuted foodstuffs to a fluid, the apparatus including:

(a) a contactor body including a foodstuff flow passage;

(b) a contact passage comprising a portion of the foodstuff flow passage through the contactor body, the contact passage being defined between opposing contact passage walls; and (c) a fluid communication arrangement providing fluid coimnunication through the contactor body to the contact passage. i

8. The apparatus of Claim 7 further including a fluid chamber within the contactor body and located outside of the contact passage, and wherein the contact passage is defined between two substantially planar and parallel contact passage walls.

9. The apparatus of Claim 8 wherein the fluid communication arrangement provides fluid communication between the fluid chamber and the contact passage through both of the substantially planar contact passage walls.

10. The apparatus of Claim 7 wherein the fluid communication arrangement comprises a number of discrete openings extending into the contact passage.

11. The apparatus of Claim 10 wherein the discrete openings have a maximum transverse dimension large enough for enabling a fluid in the fluid chamber to flow into the contact passage to effect a desired contact with the foodstuff in the contact passage, and small enough for inhibiting the foodstuff from flowing therethrough.

12. The apparatus of Claim 7 wherein the fluid communication arrangement comprises a porous and permeable material interposed between a fluid chamber and the contact passage.

13. An apparatus for exposing comminuted foodstuffs to a fluid, the apparatus including:

(a) a contactor body including a foodstuff flow passage;

(b) a contact passage comprising a portion of the foodstuff flow passage through the contactor body, the contact passage being defined between two opposing and substantially planar contact passage walls spaced apart by a contact passage dimension;

(c) an inlet end section having an inlet flow area reducing from an inlet dimension to the contact passage dimension;

(d) an outlet end section having an outlet flow area reducing from an outlet dimension to the contact passage dimension;

(e) a fluid chamber included in the contactor body adjacent to the contact passage; and

(f) a fluid communication arrangement providing fluid communication between the fluid chamber and the contact passage.

14. The apparatus of Claim 13 wherein the fluid communication arrangement comprises a number of discrete openings extending from the fluid chamber to the contact passage.

15. The apparatus of Claim 14 wherein the discrete openings have a maximum transverse dimension large enough for enabling a fluid in the fluid chamber to flow into the contact passage to effect a desired contact with the foodstuff in the contact passage, and small enough for inhibiting the foodstuff from flowing therethrough.

16. The apparatus of Claim 13 wherein the fluid communication arrangement comprises a porous and permeable material interposed between the volume of the fluid chamber and the contact passage.

17. A method for exposing a comminuted foodstuff to a processing fluid, the method including the steps of:

(a) producing a substantially planar flowing sheet of the comminuted foodstuff, the flowing sheet having a minimum transverse dimension determined by the size of the pieces of material making up the comminuted foodstuff; and

(b) enabling the processing fluid to contact the flowing sheet of the comminuted foodstuff within one of the major surfaces of the flowing sheet of material.

18. The method of Claim 17 wherein the minimum transverse dimension of the flowing sheet of comminuted foodstuff is substantially equal to a dimension of the pieces of material making up the comminuted foodstuff.

19. The method of Claim 17 wherein the step of enabling the processing fluid to contact the flowing sheet of comminuted foodstuff includes directing the processing fluid through a number of discrete openings extending through one of two opposing surfaces that define a flow area for the sheet of comminuted foodstuff.

20. The method of Claim 17 wherein the step of enabling the processing fluid to contact the flowing sheet of comminuted foodstuff includes directing the processing fluid through a porous and penneable material included in one of two opposing surfaces that define a flow area for the sheet of comminuted foodstuff.

21. The method of Claim 17 wherein the step of enabling the processing fluid to contact the flowing sheet of comminuted foodstuff includes directing the processing fluid through openings in both of two opposing surfaces that define a flow area for the sheet of comminuted foodstuff.

22. The method of Claim 21 further including the step of supplying the processing fluid from a processing fluid chamber having a portion adjacent to one of two opposing surfaces that define a flow area for the sheet of comminuted foodstuff and a portion adjacent to the other one of the two opposing surfaces that define the flow area for the sheet of comminuted foodstuff.

23. A sparging screen including: (a) a number of screen passages extending transversely through a screen body from a first side of the screen body to a second side of the screen body;

(b) a first fluid chamber within the screen body; and

(c) a first fluid communication device positioned in the screen body between the first fluid chamber and a respective one of the screen passages at a location between the first side of the screen body and the second side of the screen body, the first fluid communication device providing fluid communication from the first fluid chamber to the area defined by the respective screen passage.

24. The sparging screen of Claim 23 further including a fluid inlet passage formed in the screen body and extending from an exterior surface of the screen body to the first fluid chamber.

25. The sparging screen of Claim 23 wherein the screen body includes a first side component and a second side component, the first side component including a first portion of each screen passage and the second side component including a second portion of each screen passage, the first side component aligning with the second side component so that the first portion of each respective screen passage aligns with the second portion of each screen passage.

26. The sparging screen of Claim 25 wherein the first fluid chamber is formed at an interface between the first side component and the second side component.

27. The sparging screen of Claim 26 wherein the first fluid communication device comprises a section of porous and permeable material interposed between the respective screen passage and the first fluid chamber.

28. The sparging screen of Claim 25 wherein the first fluid communication device includes at least one sparging passage extending from the first fluid chamber to the respective screen passage.

29. The sparging screen of Claim 23 further including:

(a) a second fluid chamber within the screen body separate from the first fluid chamber; and

(b) a second fluid communication device positioned in the screen body between the second fluid chamber and the respective one of the screen passages at a location between the first side of the screen body and the second side of the screen body, the second fluid communication device providing fluid communication from the second fluid chamber to the area defined by the respective screen passage.

30. The sparging screen of Claim 23 wherein:

(a) the first side of the screen body is substantially circular in shape and the screen passages are spaced apart across the first side of the screen body; and

(b) the sparging screen includes for each screen passage a respective first fluid communication device positioned in the screen body between the first fluid chamber and the respective screen passage at a location between the first side of the screen body and the second side of the screen body, each first fluid communication device providing fluid communication from the first fluid chamber to the area defined by the respective screen passage.

31. A sparging device including:

(a) an inlet chamber;

(b) a number of sparger passages, each sparger passage extending from a respective passage inlet in communication with the inlet chamber to a respective passage outlet; (c) a first fluid chamber defining a first chamber area through which at least one respective sparger passage extends; and (d) a first fluid communication device associated with each sparger passage extending through the first chamber area, the respective first fluid communication device enabling fluid communication between the first fluid chamber and an interior of the respective sparger passage.

32. The sparging device of Claim 31 further including:

(a) a second fluid chamber defining a second chamber area through which at least one respective sparger passage extends, the second chamber area being separate from the first chamber area; and (b) a second fluid communication device associated with each sparger passage extending through the second chamber area, the respective second fluid communication device enabling fluid communication between the second fluid chamber and an interior of the respective sparger passage.

33. The sparging device of Claim 32 further including:

(a) an inlet side component having a number of openings formed therein;

(b) an intermediate component having a number of openings formed therein, the intermediate component openings aligning with the openings formed in the inlet side component when the intermediate component is placed with the inlet side component in an operating position; and

(c) an outlet side component having a number of openings formed therein, the outlet side component openings aligning with the openings formed in the intermediate component when the intermediate component is placed with the outlet side component in an operating position, and (d) wherein the first fluid chamber is defined at an interface between the inlet side component and the intermediate component, and the second fluid chamber is defined at an interface between the intermediate component and the outlet side component.

34. The sparging device of Claim 33 wherein each sparger passage is defined by a respective sparger sleeve mounted in a respective sleeve receiving opening, each sleeve receiving opening being made up of a respective inlet side component opening, a respective intermediate component opening, and a respective outlet side component opening.

35. The sparging device of Claim 34 wherein each first fluid communication device associated with a respective sparger passage and each second fluid communication device associated with a respective sparger passage is formed in the respective sparger sleeve.

36. The sparging device of Claim 35 wherein each sparger sleeve includes: (a) a first porous and permeable material section aligning with the first fluid chamber; and (b) a second porous and permeable material section aligning with the second fluid chamber.

37. The sparging device of Claim 32 further including a pressure application device associated with the inlet chamber for forcing material from the inlet chamber through the sparger passages.

38. The sparging device of Claim 32 further including: (a) a scraper plate adjacent to the inlet chamber, the scraper plate having a number of plate opemngs, each plate opening aligning with a different one of the sparger passages; and (b) a scraper blade mounted in the inlet chamber in position to scape across plate openings of the scraper plate to sever material between a blade edge associated with the scraper blade and a respective scraper plate opening edge associated with each scraper plate opening.

39. A method for adding a fluid to a foodstuff, the method including the steps of:

(a) directing the foodstuff through a number of sparger passages from an inlet end of each respective passage to an outlet end of each respective passage; (b) applying a first fluid to the foodstuff in two or more sparger passages at a point between the inlet end and outlet end of the respective sparger passages; and

(c) applying a second fluid to the foodstuff in two or more sparger passages at a point between the inlet end and outlet end of the respective sparger passages.

40. The method of Claim 39 wherein the step of directing the foodstuff through the sparger passages includes forcing the foodstuff into the inlet ends of the respective sparger passages with an auger.

41. The method of Claim 39 further including the step of periodically moving a cutting element over a cutting surface associated with the inlet end of each respective sparger passage.

42. The method of Claim 41 wherein the step of periodically moving the cutting element over the cutting surface is performed with a blade connected to an auger.

43. The method of Claim 42 wherein the first fluid and the second fluid are each applied to the foodstuff through a respective porous and permeable material making up a portion of the respective sparger passage.

44. The method of Claim 39 wherein the first fluid and the second fluid are each applied to the foodstuff through a different set of transverse openings formed in the respective sparger passage.

45. The method of Claim 39 wherein the first fluid and second fluid are applied to the foodstuff in the same respective sparger passages.