This invention relates to meat processing operations and equipment. More particularly, the invention relates to methods and apparatus for producing a carbon monoxide treated comminuted meat product.
It has long been known that carbon monoxide may be used to produce a bright red color in a meat product. U.S. Pat. No. 4,522,835 to Woodruff et al. discloses a process of treating meat products with carbon monoxide gas to modify the color at the surface of the meat product.
It has also been proposed to use carbon monoxide gas as a preservative in meat products. U.S. Pat. No. 6,270,829 to Shaklai discloses a process where raw meat is exposed to carbon monoxide gas for a sufficient period to saturate the meat with carbon monoxide to inhibit microbial activity in the meat product. The Shaklai patent also discloses that the carbon monoxide saturation in the meat product produces a color change throughout the meat product.
Carbon monoxide gas has also been used in an injection material to treat meat products. U.S. Pat. No. 3,119,696 to Williams discloses injecting meat with a water and gas combination for the purpose of improving the tenderness of the meat. The Williams patent discloses that the gas is included in the water/gas treatment material to help facilitate absorption of the water fraction into the meat. The Williams patent also discloses that carbon monoxide may be included in the gas portion of the water/gas combination in order to modify the color of the meat in the interior of the meat product.
The change in color from carbon monoxide treatment results from the reaction of carbon monoxide with hemoglobin and myoglobin in meat products to form carboxyhemoglobin and carboxymyoglobin respectively. The microbial activity inhibiting effect of carbon monoxide in meat products is at least in part produced by reducing the oxygen content in the meat product. This reduction in oxygen content creates an unsuitable environment for aerobic microbes. Carbon monoxide treatment may also inhibit the growth and propagation of anaerobic microbes as well.
Despite the benefits, there remain certain problems associated with treating meat products with carbon monoxide. One problem with treating uncooked meats with carbon monoxide is that the treatment may affect the color of the product after the meat begins to spoil and after cooking. In particular, prior art carbon monoxide treatments may produce a bright red color that persists in the uncooked meat even after the meat begins to spoil due to microbial activity in the meat. Thus, prior art carbon monoxide treatments may mask spoilage in a meat product. Also, prior art carbon monoxide treatments may leave the uncooked meat with a bright red color that remains in the meat even after the meat is cooked. This unnatural red color in the cooked meat product occurs throughout the product where the entire product is saturated with carbon monoxide. Even where only the surface of the meat product is saturated with carbon monoxide, the surface of the cooked meat product may have an unnatural red color and the meat may not brown properly. Thus, although the carbon monoxide treated, uncooked meat product may have an appearance that is desirable to consumers, the color in the uncooked meat product may mask spoilage and the color remaining in the cooked meat product may be unacceptable to consumers.
The present invention provides methods for producing a carbon monoxide-treated comminuted meat product while reducing or eliminating the problems associated with spoilage masking and unnatural color in the uncooked and cooked meat products. It is noted that the term “meat product” is used here and throughout this disclosure and the accompanying claims to refer to meat alone, including lean portions, fat, and related materials of beef, pork, poultry, or seafood, and to refer to meat that has been mixed with, or includes, additives such as flavorings, extenders, tenderizing agents, and other materials.
One preferred method embodying the principles of the invention includes applying a treatment material containing carbon monoxide to an initial meat product to produce an intermediate meat product. Once the treatment material containing carbon monoxide is applied to the initial meat product to produce the intermediate product, the intermediate meat product is comminuted to produce a final comminuted meat product.
The treatment material containing carbon monoxide may be any liquid or gaseous material containing carbon monoxide either in gaseous form or in solution in a carrier liquid. A treatment material containing carbon monoxide within the scope of the invention may include any suitable material in addition to carbon monoxide, and any additional materials may be in gaseous or liquid form. One preferred treatment material containing carbon monoxide comprises a suitable carrier liquid having carbon monoxide in solution. More particularly, one preferred treatment material containing carbon monoxide comprises a solution of water and carbon monoxide.
Some preferred methods according to the present invention further include applying a pH modifying material to the initial meat product or intermediate meat product. The pH modifying material may be applied as either a pre-treatment before applying the carbon monoxide-bearing treatment material, as part of the treatment material containing carbon monoxide, or as a post-treatment after applying the treatment material containing carbon monoxide. Preferred pH modifying materials include ammonia-based pH modifying materials such as ammonia gas and ammonium hydroxide solution, and carbon dioxide-based pH modifying materials such as carbon dioxide gas and carbonic acid solutions.
The initial meat product to which the present invention is applied may be whole animal carcasses or whole portions of an animal carcass such as a half or quarter. An initial meat product within the scope of the invention may also comprise a more highly processed meat such as bone-in or boneless cuts of meat such as bone-in or boneless steaks or roasts, or filets.
The designation “intermediate meat product” is used in this disclosure and the accompanying claims as simply one way to refer to meat products to which the treatment material containing carbon monoxide has been applied, as distinguished from meat that has not yet received any carbon monoxide treatment. Also, the terms “apply” and “applied” when used in connection with a treatment with any treatment material are intended to encompass any manner in which the particular treatment material may be applied. For example, a treatment material may be applied according to the invention by placing the treatment material in contact with a surface of the meat product to be treated or by injecting the treatment below the surface of a meat product via an injection conduit. Treatment materials may also be applied by surface application and by injection concurrently, or as discrete steps.
The comminution of the intermediate meat product may be accomplished in any suitable fashion within the scope of the present invention, either in a single comminution step or as multiple distinct steps. For example, where the initial meat product is a whole carcass or a half or quarter, the comminution may include first conducting trimming operations and then deboning, and then the trimmings or deboned meat, or both, may be further comminuted using a suitable comminuting device such as a meat grinder or bowl chopper. As another example, where the initial meat product has already been deboned, the intermediate meat product produced by the application of treatment material containing carbon monoxide may simply be comminuted by passing the intermediate meat product through a grinder or chopping the intermediate meat product in a bowl chopper. Regardless of the manner in which the intermediate meat product is comminuted, the comminution preferably produces a product made up primarily of meat product pieces measuring less than approximately two inches along their longest side, that is, having a major dimension of less than approximately two inches.
Treatments according to the present invention preferably result in a comminuted meat product having a carbon monoxide saturation of less than complete, that is, less than 100% saturation. As used in this document, complete or 100% carbon monoxide saturation in a meat product refers the case where all of the available hemoglobin and myoglobin in the meat product has been reacted with carbon monoxide to produce carboxyhemoglobin and carboxymyoglobin respectively. It will be noted that this does not necessarily mean that all hemoglobin and all myoglobin has been reacted since some hemoglobin and myoglobin in a meat product may reside in a state in which the reaction with carbon monoxide may not occur and may thus not be available to react with the carbon monoxide. Carbon monoxide saturation levels less than complete saturation may be described in this disclosure and the following claims as a percentage relative to complete saturation. For example, as used in this disclosure and the accompanying claims, 50% carbon monoxide saturation means that one-half of the available hemoglobin and myoglobin in the meat product has been converted to carboxyhemoglobin and carboxymyoglobin, respectively.
Carbon monoxide treatment according to the invention is particularly beneficial when combined with pH modifying treatments because it believed that the carbon monoxide affects the manner in which pH modifying materials are absorbed into the meat products. In particular, it is believed that the carboxy forms of hemoglobin and myoglobin formed from carbon monoxide treatment do not allow certain constituents in the pH modifying material to be absorbed with the hemoglobin and myoglobin. These constituents of the pH modifying material are beneficially absorbed elsewhere in the meat product. It is also believed that when pH modifying material is used together with carbon monoxide, the pH modifying material may help reduce the effect of the carbon monoxide on the color of the meat product and/or help make the color change less permanent. Thus, carbon monoxide treatments according to the present invention may produce the desired microbe inhibiting effect without unduly maintaining the red color in the treated product which might mask spoilage or affect the appearance of the cooked product.
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.
Referring to
It should be noted that some of the process steps shown in
Where a preparation step is included as shown at process block 101 in
Pre-treatments and post-treatments as shown at process blocks 102 and 104 may include numerous different types of treatments within the scope of the present invention. For example, one preferred post-treatment includes applying a pH decreasing material such as carbon dioxide gas or weak carbonic acid solution to the meat product. A pH decreasing material may also be applied to the meat product as a pre-treatment. Other pre or post-treatments may include adding pure water or brines, adding flavorings, or adjusting the temperature of the highly comminuted meat product. One preferred form of the invention includes a vacuum or flushing step as a post-treatment to remove excess treatment material containing carbon monoxide prior to the comminuting step shown at process block 105 in
The comminuting step shown at process block 105 in
The step of applying a vacuum or applying a flushing medium to the treated meat product as shown at process block 106 in
Any suitable packaging or freezing and packaging may be employed as indicated at process block 107. For example, an initial meat product that has been treated with a treatment material containing carbon monoxide and then comminuted may be packaged in a traditional chub package. Alternatively, meat products that have been treated according to the invention may be packaged in any suitable modified atmosphere package. Where the product is frozen, it may first be formed into sheets, patties, or other suitable shapes and then frozen by a suitable freezing device. Alternatively, a meat product that has been treated according to the present invention may be frozen in the form of a sheet and then cut into chips which are then packaged in a suitable manner.
The treatment material containing carbon monoxide may be applied in substantially any suitable manner at process block 103 in
The apparatus used to apply the treatment material containing carbon monoxide may vary depending upon the nature of the initial meat product to which the treatment material is applied. For deboned meat products, the treatment material containing carbon monoxide may be injected into the interior of the meat product using a suitable injection system with one or more injection needles/conduits.
Although some preferred forms of the invention utilize a carbon monoxide treatment material in which substantially all of the carbon monoxide is held in solution in a carrier liquid, some carbon monoxide in such a carbon monoxide treatment material may also be in the form of a gas suspended in the carrier liquid or as a gas atomizing/vaporizing the carrier liquid. Also, carbon monoxide may be applied as a gas. Whether the carbon monoxide is applied as a gas or in solution, or both in solution and in gas form, the carbon monoxide may be from any suitable source. For example, carbon monoxide may be supplied from a cylinder containing commercially produced pure carbon monoxide, or may be supplied from a food grade smoke generator. Regardless of the form or source of carbon monoxide applied to the highly comminuted meat product, the total carbon monoxide content in the carbon monoxide-bearing material applied as indicated at process block 103 in
The desired carbon monoxide saturation level in the treated meat product may vary with the nature of the meat product being treated. In some meat products, such as those that have or will have added seasonings, carbon monoxide saturation may approach 100% saturation. In lightly seasoned or unseasoned meat products, such as plain ground beef for example, the desired carbon monoxide saturation according to the invention remains below 100% saturation, and preferably less than approximately 95%. Carbon monoxide saturation levels at approximately 70%, 60%, 50%, and 40% may also be used according to the invention. Again, depending upon the meat product being treated, the desired carbon monoxide saturation level may range from approximately 5% to 95% saturation. It should also be noted that the desired carbon monoxide saturation level in the treated meat product may vary with the amount of liquid added to the meat product. For example, a meat product treated according to the invention with added liquid content at 20% by weight with the meat may allow a higher desired carbon monoxide saturation level than at an added liquid content at 5% by weight with the meat. In any event, the carbon monoxide saturation level in the meat product treated according to the present invention should include a carbon monoxide saturation level or content low enough for the particular comminuted meat product to allow the meat product to brown properly in the course of cooking and to show visible signs of spoilage in the meat product when the product spoils due to bacterial activity.
The resulting pH in a comminuted meat product that has been treated with carbon monoxide and an ammonia-based pH increasing material according to the present invention may range from 5.6 to 8.0 or higher. Good results have been produced where the carbon monoxide/pH treated meat product had a final pH of 6.5 to 6.7 as well as where the treated product had a pH of 7.4. The pH of an ammonium hydroxide solution applied to the meat product may range from 8.5 to 11.6 or more. It should also be noted that the desired pH of an ammonium hydroxide solution comprising the ammonia-based pH increasing material applied at process block 103 in
Where the ammonia-based pH increasing material comprises ammonium hydroxide solution and is applied separately before applying carbon monoxide, or where a pre-treatment application of water is employed in the process illustrated in
Where treatment material containing carbon monoxide is applied in a gas mixture at process block 103 in
Some preferred forms of the invention may perform the pre-treatment and/or post-treatment steps in rapid succession with the carbon monoxide and ammonia-based material treatment step shown at block 103 in
Treatment system 200 also includes an ammonia gas supply 210 that directs ammonia gas to mixing device 201 through connecting line 211. A suitable pressure regulator 212 is included in line 211 to control the flow of ammonia gas to mixing device 201. Mixing device 201 receives carbon monoxide gas, ammonia gas, and the carrier liquid, water for example, and mixes the materials or allows the materials to mix to produce a suitable treatment fluid containing the desired carbon monoxide content and ammonia content. This combined treatment fluid is directed through line 215 to be applied to an initial meat product.
A carbon monoxide application device (also referred to herein as a “CO application device”) 218 is included in treatment system 200 to receive the treatment fluid containing carbon monoxide and ammonia through line 215 and to apply the treatment fluid to an initial meat product supplied to, or contained in, the CO application device. The treatment system 200 shown in
It will be appreciated that the diagrammatic representation of
Mixer 201 may be any suitable device or combination of devices for receiving the carrier liquid, carbon monoxide, and ammonia gas and mixing the materials together to produce the desired carbon monoxide/ammonia-based material treatment fluid. For example, mixer 201 may be a sparging device or multiple sparging devices for adding the carbon monoxide gas and ammonia gas to the carrier liquid. Alternatively, mixer 201 may include one or more devices in which the carbon monoxide and ammonia-base treatment material are added to the carrier liquid through a permeable or semipermeable membrane as the carrier liquid flows through the device or devices. In any case, where the carbon monoxide and ammonia are added to the carrier liquid separately, the ammonia is preferably applied to the carrier liquid first and then the carbon monoxide. This may help reduce the carbon monoxide gas in the resulting treatment material which may be advantageous for some implementations of the invention.
CO application device 218 shown in
In forms of the invention intended to treat large initial meat products having a smallest dimension well over two inches, CO application device 218 preferably includes an injection system having one or more injection conduits to inject the treatment material containing carbon monoxide into the interior of the meat product in addition to perhaps applying the treatment material to the surface of the initial meat product. Further details of a suitable injection device will be described below with reference to
The grinder 222 shown in
There may be a benefit to allowing a certain minimum amount of time to elapse between the application of carbon monoxide-bearing treatment material according to the invention and the time that the treated meat product is comminuted at grinder 222. It is believed that the storage time allows the added materials to better distribute and equilibrate through the meat product. To accommodate a suitable storage time there may be a storage facility interposed between CO application device 218 and grinder 222. Any storage of the carbon monoxide treated meat is preferably done under a controlled atmosphere at a suitable storage temperature.
The example treatment system 200 shown in
Packaging system 228 may be any packaging system suitable for the carbon monoxide-treated, comminuted meat product produced according to the present invention. For example, packaging system 228 may be a chub packaging device, or a modified atmosphere packaging device. It is also possible to package the comminuted meat product in standard trays without any modified atmosphere.
Injection system 300 shown in
Each treatment station 301, 302, and 303 shown in
The injection pressures suitable for use in injecting a treatment material containing carbon monoxide, pre-treatment material, and post-treatment material according to the present invention generally coincide with those pressures used for injecting brines into meat products as known in the prior art. The injection pressures may vary depending upon the temperature and nature of the meat being treated, the size of injection conduits employed, the exit openings in the injection conduits, and the amount of material to be added to the meat product. Where the initial meat product is made up of beef steaks at 35 degrees Fahrenheit, for example, 2.5 bars is a suitable pressure for injecting material to produce a content of added solution at 10% by weight with the meat, and 3.5 bars is a suitable pressure for injecting material to produce a content of added solution at 20% by weight with the meat. Lower injection pressures are also possible within the scope of the invention, depending upon the nature of the injection device.
It will be appreciated that the meat product 308 being treated in injection system 300 shown
An injection conduit 305 used to inject the carbon monoxide-bearing treatment material and other materials into the volume of a meat product according to the present invention may include any suitable conduit or needle suitable for penetrating the surface of the meat product so that the desired treatment material may be injected into the volume of the meat product. Preferred forms of the invention utilize elongated injection conduits with a sharp distal end for piercing the surface of the meat product and preferably a number of injection passages spaced apart along the length of the injection conduit that penetrates into the interior of the meat product. Rather than discrete injection openings, one or more areas of porous and permeable material such as a plastic, ceramic, or cintered metal may be included along the length of the injection conduit 305 to provide one or more areas through which the treatment material may flow from the conduit into the volume of the meat product being treated. Some forms of the invention may include injection conduits that include porous and permeable material along their entire length with an axial passage extending there through and with a solid distal portion to provide a sharp tip. Still other forms of the invention may include injection conduits of different lengths and with injection flow passages positioned at different penetration depths in the volume of the meat product. These and any other suitable arrangement of injection conduits may be used to distribute the treatment material containing carbon monoxide and other liquids or fluids into the volume of the meat product to ensure the desired carbon monoxide treatment and distribution according to the present invention.
The present invention encompasses numerous variations on the injection system shown in
In preferred forms of the invention, the different injection points for the CO treatment material and for the pre-treatment and post-treatment materials are spaced apart on approximately one-eighth (⅛) of an inch to one (1) inch centers across the meat product being treated. Generally, the closer the spacing the better, subject to physical limitations of the injection conduits and the impact of the injection conduits on the meat. Where injection conduits are inserted at different points to provide the desired injection coverage, the different insertion points are also spaced apart between one-eighth-(⅛) of an inch to one (1) inch. Any suitable needle or injection conduit may be used in the present invention. The outer diameter of preferred needles or injection conduits may range from 2 to 6 millimeters or more. Also, where the meat product being treated may include bones, the injection system may include an arrangement for enabling an injection conduit 305 to be axially displaced in the event it is pressed into a bone in the meat product.
As used herein, whether in the above description or the following claims, the terms “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” and the like are to be understood to be open-ended, that is, to mean including but not limited to. Only the transitional phrases “consisting of” and “consisting essentially of,” respectively, shall be closed or semi-closed transitional phrases, as set forth, with respect to claims, in the United States Patent Office Manual of Patent Examining Procedures (Eighth Edition, August 2001 as revised May 2004), Section 2111.03.
Use of ordinal terms such as “first,” “second,” “third,” etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed. Such ordinal terms are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term).
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.
This application is a continuation-in-part of U.S. patent application Ser. No. 11/502,841, filed Aug. 11, 2006, and entitled “Method for Treating Meat Products With Carbon Monoxide,” which is a continuation of U.S. patent application Ser. No. 10/795,000, filed Mar. 5, 2004, and entitled “Method and Apparatus for Treating Meat Products With Carbon Monoxide.” The benefit of these prior applications is hereby claimed in the present application pursuant to 35 U.S.C. §120. This application also claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application Ser. No. 60/736,631, filed Nov. 15, 2005, and entitled “Method and Apparatus for Treating Meat Products With a Treatment Liquid Containing Carbon Monoxide.” The entire content of each of these prior applications is incorporated herein by this reference.
Number | Date | Country | |
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60736631 | Nov 2005 | US |
Number | Date | Country | |
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Parent | 10795000 | Mar 2004 | US |
Child | 11502841 | Aug 2006 | US |
Number | Date | Country | |
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Parent | 11502841 | Aug 2006 | US |
Child | 11510418 | Aug 2006 | US |