SUPPORT MATERIAL FOR THE PREPARATION OF FOODSTUFFS

Abstract: The invention includes methods for treating foodstuffs using support materials. Comprising an elastomeric layer (9), polymer blend layer (8), to layer (7), and polyethylene layer (6).

Description: SUPPORT MATERIAL FOR THE PREPARATION OF FOODSTUFFS Field of the Invention The present invention relates to methods for the treatment of foodstuffs using support materials. Background of the Invention The preparation of foodstuffs, particularly in industrial applications, often involves multiple processing steps such as freezing, storing, thawing and heating. It is important throughout all of these steps that exposure to the environment be kept to a minimum to avoid the possibility of bacterial contamination. It is thus preferable to keep the food in a single support material, such as a container bag, at all times prior to final preparation for consumption. Conventional metnods of handling foodstuffs, however, often involve multiple containers because of limitations in the container materials. For example, polyethylene bags have been successfully used for the storage of foodstuffs, but the food must be removed from the bags prior to heating because of the potential for bag melting and the resulting adherence to the food or incorporation into the food. Consequently, in some applications, foodstuffs such as meat products are stored in polyethylene bags at low temperatures, removed from the bags prior to heating, and then placed into and heated within a suitable temperature-resistant material such as aluminum foil or nylon. In addition to the potential for bacterial contamination when foodstuffs are transferred between containers, many of the container materials amenable to high-temperature cooking applications stick to the food after cooking. For example, the use of nylons and other materials that withstanding cooking temperatures often results in a loss in food yield of 5- 10% or more due to sticking. There is thus a need for a non-toxic material in which foodstuffs can be frozen, stored, thawed and/or heated without removal, and with which the food is substantially non-adherent at both low and high temperatures. Summary of the Invention The present invention relates to methods for treating foodstuffs using support materials. In one exemplary embodiment, the invention is a method for preparing foodstuffs, which includes placing the foodstuffs in contact with a support material; heating the foodstuffs while maintaining contact between the foodstuffs and the support material; and separating the foodstuffs from the support material. The support material of the present invention has one or more layers. In a preferred embodiment, at least one of the one or more layers is an elastomeric polymer layer. In embodiments where the support material has two or more layers, preferably at least one of the layers is an elastomeric polymer layer and at least one of the layers is a polymer or polymer blend layer. One advantage of the present invention is that it provides methods for treating foodstuffs in which the foodstuffs are kept in contact with a single support material throughout all processing steps, thus simplifying the treatment process and minimizing exposure of the foodstuffs to bacteria. Another advantage of the present invention is that it provides methods for treating foodstuffs in which the foodstuffs are contacted by a support material that is resistant to both cold and hot temperatures. Another advantage of the present invention is that it provides methods for treating foodstuffs in which the foodstuffs are contacted by a support material that is substantially non-adherent to the foodstuffs. Yet another advantage of the present invention is that it provides methods for treating foodstuffs in which the foodstuffs are contacted by a support material having sufficient mechanical strength at all applicable temperatures to support and/or contain the foodstuffs. Brief Description of the Drawings Fig. 1 is a cross-sectional view of a support material in accordance with an embodiment of the present invention, which has a support material that is two or more layers; Fig. 2 is a cross-sectional view of a support material in accordance with an embodiment of the present invention, which has a support material that is two or more layers; and Fig. 3 is a cross-sectional view of a support material in accordance with an embodiment of the present invention which has a support material that is two or more layers. Detailed Description The present invention relates to methods for "treating" (i.e., packaging, preparing, encasing, storing, cooking, etc.) foodstuffs using support materials. Preferred methods include placing foodstuffs in contact with a support material; heating the foodstuffs while maintaining contact between the foodstuffs and the support material; and separating the foodstuffs from the support material. Foodstuffs include any substance that can be used or prepared for use as food. Example of foodstuffs include solid foodstuffs such as meat, vegetables, and fruits, and liquid foodstuffs such as soups and sauces. Heating involves raising the temperature above room temperature. Preferably, heating involves raising the temperature of the foodstuffs to greater than about 100°F. More preferably, the temperature is raised to a temperature of greater than about 140°F. Even more preferably the temperature is raised to a temperature of greater than about 212° F to less than about 410° F. Most preferably the temperature is raised to a temperature of greater than about 300°F to less than about 410°F. Heating may be accomplished in several ways known to those skilled in the art. For instance, heating may be accomplished by placing the foodstuffs in boiling water or heating in a microwave oven or a conventional oven. In an embodiment of the present invention, the foodstuffs are at a temperature above room temperature prior to being placed in contact with said support material. In this embodiment, the foodstuffs are preferably at a temperature greater than about 100°F when placed into contact with the support material. The method of treating foodstuffs may further include storing the foodstuffs after placing the foodstuffs in contact with the support material. In one embodiment, storing the foodstuffs is accomplished by freezing. In this embodiment, the foodstuffs are thawed after being frozen. Preferred support materials include elastomeric support materials characterized by high strength and temperature resistance, and which are substantially non-adherent to foodstuffs to thereby result in the complete or near-complete release of foods after heating. As used herein, "support material" refers to any structure that facilitates food storage and/or preparation, such as films, sheets, bags, containers, and the like. The preferred support material of the invention is in the form of a sealed bag, which has the ability to house foodstuffs throughout food treatment processes such as freezing, storage, thawing and heating. Suitable bags are optionally gussetted or clipped. As an example, a gussetted bag measuring about 22 x 7.5 x 3.25 inches made from a 0.002 inch-thick film is suitable for housing a 10 pound quantity of meat. Support materials of the present invention include materials having at least one layer, at least one of which preferably includes an elastomeric polymer layer having at least one suitable elastomeric polymer. Non-limiting examples of suitable elastomeric polymers include those based on polyether esters, polyester esters, polyether gylcols, elastomeric copolymers, and polyamide elastomers preferably based on nylon 6 or nylon 12, and mixtures and copolymers thereof. Specific examples include acrylonitrile-butadiene copolymers, brominated isobutylene-isoprene copolymers, butadiene-acrylonitrile-ethylene glycol dimethacrylate copolymers, butadiene-acrylonitrile-methacrylic acid copolymer, butadiene- styrene-methacrylic acid copolymer. chloroprene polymers, chlorotrifluoroethylene, vinylidene fluoride copolymer, di (4-methylbenzoyl) peroxide, ethylene-propylene copolymer elastomers, ethylene-propylene- dicyciopentadiene copolymers, ethylene-propylene-1 ,4-hexadiene copolymers, hydrogenated butadiene/acrylonitrile copolymers, isobutylene- isoprene copolymers, polyamide/polyether block copolymers, polybutadiene, polyester elastomers, polyisoprene, polyurethane resins, silicone basic polymer, styrene-butadiene copolymer, vinylidene fluoride- hexafluoropropyiene copolymers, and vinylidene fluoride- hexafluoropropylene-tetrafluoroethylene copolymers. Preferred elastomeric polymer layers of the invention include layers containing polyester elastomers, such as HYTREL ® (butylene/poly(alkylene ether) phthalate available from DuPont Co.) and ARNITEL ® (a polyester elastomer available from DSM Co.), and nylon elastomers such as GRILON ® (EMS Co.). In other embodiments of the present invention the support material includes at least two layers. Preferably, at least one layer is an elastomeric polymer layer as described above, and at least one layer is a polymer or polymer blend layer. The polymer or polymer blend layer preferably provides a barrier to oxygen and/or moisture. Examples of suitable polymers for use in such a layer include polymers and copolymers of nylon, polyester, ethylene, vinyl alcohol, polyvinylidene chloride, ethylene vinyl acetate, and other polymers that act as functional barriers. In a preferred embodiment, the polymer or polymer blend layer is Nylon 6 or a polymer blend with Nylon 6. In one embodiment of the present invention where the support material includes at least two layers, an elastomeric polymer layer and a polymer or polymer blend layer are attached to one another either directly or indirectly. Such an attachment may be a direct attachment, or the layers may be attached to one another by a tie layer or adhesive there-between. Suitable tie layers include for example, Ethyl vinyl alcohol or an ethylene copolymer. Fig. 1 shows the polymer or polymer blend layer 1 and the elastomeric blend layer 2 being directly attached to one another. Fig. 2 shows a polymer or polymer blend layer 3 attached to an elastomeric polymer layer 5 via a tie layer 4 formed there-between. The adherence of the polymer or polymer blend layer and the elastomeric polymer layer is a factor controlling whether or not tie layers, adhesives or the like are needed in order to attach the layers to one another. Given suitable adherence between the layers, the layers can simply be co-extruded, laminated or attached to one another by other suitable methods. Suitable materials for use as tie layers in the present invention include polyethylene copolymers, ester based polymers, polyether based polymers, glycol base polymers, ethylene vinyl acetate, ethylene vinyl alcohol, polyvinylidene chloride and other materials providing the desired adhesion properties. Alternatively, suitable adhesive materials, such as polymeric adhesives can be used. In one embodiment of the invention, in order to improve the adherence of layers, one or more tie layers is added, which contains a primary polymer and additionally at least one secondary polymer in an amount that is smaller than the amount of the primary polymer. In another embodiment of the present invention, additional layers are added to at least one polymer or polymer blend layer and at least one elastomeric polymer layer. For instance, additional polymer or polymer blend layers or elastomeric polymer layers are added to the support material as desired, for reasons such as, further decreasing oxygen and/or moisture permeability of the support material. In a preferred embodiment, a layer of polyethylene is added to the support material to further decrease oxygen and/or moisture permeability. The layers may all be co-extruded together in order to adhere to one another. Alternatively, tie layers or adhesives are added, as necessary, to adhere additional layers to the at least one polymer or polymer blend layer or to the at least one elastomeric polymer layer. Fig. 3 depicts an embodiment of the support material having an elastomeric polymer layer attached directly to a polymer or polymer blend layer δ. which is attached to a polyethylene layer 6 via a tie layer 7. In certain embodiments of the present invention where the support material has at least two layers, the layers of the support material are attached to one another by one of several methods, including lamination, co-extrusion or the like, in an embodiment where lamination is performed, lamination is performed by conventional lamination techniques. In an embodiment where co-extrusion is performed, co-extrusion is performed by conventional co-extrusion techniques. In this embodiment, the layers of the support material are co-extruded either simultaneously or extruded or co-extruded separately from one another. In one embodiment where an elastomeric polymer layer and polymer or polymer blend layer are co-extruded simultaneously, the layers are directly attached to one another. In another embodiment, elastomeric polymer layer, a tie layer and polymer or polymer blend layer are co- extruded simultaneously, resulting in the layers adhering to one another via a tie layer. Alternatively, in other embodiments where the support material has at least two layers, the layers are extruded or co-extruded separately and then attached to one another by lamination or other methods. In one embodiment the separately extruded layers of the support material are laminated together such that they adhere directly to one another, in another embodiment, the separately extruded layers are laminated together, and at least two of the layers have a tie layer or adhesive there-between, to increase the strength of the attachment between the layers. In a preferred embodiment, the support material is a polymer or polymer biend with Nylon 6 directly attached to an elastomeric polymer layer. In another preferred embodiment, the support material is a polymer or polymer blend layer of Nylon 6, which is attached to an elastomeric polymer layer via a tie layer of ethylvinyl alcohol formed there¬ between. In another preferred embodiment, the support material includes an elastomeric polymer layer directly attached to a nylon polymer blend layer, which is attached to a polyethylene layer via a tie layer of ethylene copolymer. The elastomeric polymer layer of the support material of the present invention, whether it be a support material having a single layer or multiple layers, may include at least one additional polymer, in addition to the elastomeric polymer. The elastomeric polymer layer may thus include at least one other polymer in addition to the suitable elastomeric polymers described above. The additional polymer may be mixed or blended with the elastomeric polymer. The additional polymer may or may not be elastomeric itself. The additional polymer may be selected based on factors such as reducing the cost or price of the final product, increasing heat resistance, and decreasing oxygen permeability. The relative proportions of polymers in the elastomeric polymer layer may be determined based on similar factors. Non-limiting examples of additional polymers that may be used in accordance with the present invention include nylons, such as Nylon 6, Nylon 66, Nylon 666, Nylon 10, Nylon 11 , and Nylon 12; copolymers of nylons; polyesters; copolymers of polyesters; polyestyrenes; polyethylenes; copolymers of polyethylenes and the like. The support materials of the present invention, whether they have a single layer or multiple layers, optionally include at least one additive. Additives may be included within any of the layers of the support material for a variety of purposes, including to improve desired properties while not adversely affecting mechanical strength or heat resistance. For example, in one embodiment, additives such as ethylene vinyl alcohol, polyvinylidene chloride and/or SARAN ® are added to the elastomeric polymer layer to improve the ability of the elastomer to act as a barrier to oxygen or to decrease oxygen permeability. In one embodiment of the present invention, at least one additive is added to an elastomeric polymer layer, which may be the only layer of the support material or one of several layers making up the support material. In another embodiment, a polymer or polymer blend layer includes at least one additive. Support materials according to the present invention should have suitable mechanical properties, heat resistance, and release characteristics for use in the present invention. For example, the support material is preferably characterized by a tensile strength of about 5-7 ksi, an elongation at fracture of about 500-600%, a relative density of about 1.25 g/cm 3 , a melting point of about 415° F, a recommended maximum use temperature of up to about 400° F, and a foodstuff adherence of less than about 0.5% by weight. The invention is further described with reference to the following non-limiting examples. Example 1 A film comprising a polyester elastomer (ARNITEL ® , DSM Co.) was manufactured on a blown film line. The film was about 0.002 inches in thickness and gussetted to a width of about 7.5 x 3.25 inches. The film was wound onto rolls, from which bags measuring about 22 inches in length were manufactured using an AMPLAST ® seal machine. Bags were individually placed into a processed meat filling machine, which injected 10 pounds of meat into each bag. Bags were placed into cardboard boxes (four bags per box), and stored at sub-freezing temperatures for a period of at least several days. Subsequently, the boxes were removed from the freezer and the meat was thawed. While still in the bags, the meat was placed in an oven and cooked at a temperature of about 145°F (in the center of the meat) for about 4 hours. After cooking, the meat product samples were removed from each bag. Less than about 0.5% of each sample adhered to its respective bag. Example 2 A film comprising a polyether elastomer (HYTREL®, DuPont Co.) was manufactured on a blown film line. The film was about 0.0025 inches in thickness and gussetted to a width of about 7.0 x 4.0 inches. The film was wound onto rolls, from which bags measuring about 23 inches in length were manufactured using a clipping machine. Bags were individually placed into a soup filling machine, which injected about 14 pounds of hot soup into each bag. Bags were placed into cardboard boxes (five bags per box), and stored in a refrigerator. When needed for consumption, bags were introduced into an oven for heating before serving. Throughout this process, the film withstood the high temperature of the soup and kept its shape during utilization. Example 3 A film comprising a polyamide elastomer (GRILON ® , EMS Co.) was manufactured on a blown film line. The film was about 0.00125 inches in thickness and about 6.0 inches in width. The film was wound onto rolls and subsequently sheared on a 2 inch core to form sausage casings. The casings were filled by a sausage stuffing machine. The casing was clipped and cut every 15 inches to create 15 inch bag sausages. The film kept the sausage meat in its proper shape and provided an efficient bacterial barrier during handling. At consumption, the film was peeled from the sausage meat with ease. Example 4 By way of example, an elastomeric polymer layer having one or more of the following compositions, is suitable as the only layer or one of multiple layers in the support material of the present invention. 1. A polymer composition including about 1 % to about 99% by weight of polyester elastomer (for example ARNITEL ® EM 630 from DSM Co.) and about 1 % to about 99% by weight of Polyamide Nylon 6 (for example AKULON ® F-138c from DSM), where the combined weight percent of the elastomer and the polyamide is at least about 80%. 2. A polymer composition including about 75% by weight of polyester elastomer (for example ARNITEL ® EM 630 from DSM Co.), about 20% by weight of Polyamide Nylon 6 (for example AKULON ® F-138c from DSM), and about 5% by weight of Ethylene Vinyl Alcohol Copolymer resin (for example EVAL H-101 from EVAL Co. of America). 3. A polymer composition including about 80% by weight of polyester elastomer (for example ARNITEL® EM 630 from DSM Co.) and about 10% by weight of polybutylene terephthalate (polyester resin) (for example CRASTIN ® 6129 NC10 from DuPont), and about 10% by weight of Ethylene- Vinyl Acetate Copolymer (for example ELVAX ® 3128 from DuPont). 4. A polymer composition including about 80% by weight of Poiyamide Nylon 6 (for example AKULON ® F-138c from DSM), and about 20% by weight of polyester elastomer (for example ARNITEL ® EM 630 from DSM Co.) 5. A polymer composition including about 50% by weight of Polyamide Nylon 6 (for example AKULON ® F-138c from DSM), and about 50% by weight of Nylon 6 elastomer (for example GRILON ® ELX249 from EMS Co.) 6. A polymer composition including about 60% by weight of polyurethane elastomer (for example PELLETHANE ® 2100, (polyester polycaprolactone) or 2100 (polytetramethyiene giycol ether) or 2354 (polyester polycaprlactone/2355 polyester polyadipate) or 2363 (polytetramethylene glycol ether) from Dow Plastics Co.) and about 40% by weight of Polyamide Nylon 12 from EMS Co. Those skilled in the art understand that the above examples may be modified and varied, for example as to the relative amounts of each ingredient, and that the compositions may include one or more ingredients in addition to the ingredients listed as part of each example composition. The present invention provides methods for treating foodstuffs using support materials. Although the present invention has been described with respect to several exemplary embodiments having different support materials, there are many other variations of the above-described embodiments which will be apparent to those skilled in the art, even where elements have not explicitly been designated as exemplary. It is understood that these modifications are within the teaching of the present invention, which is to be limited only by the claims appended hereto.

Claims: We claim: 1. A method for treating foodstuffs, comprising: placing the foodstuffs in contact with a support material comprising at least one layer; heating the foodstuffs while maintaining contact between the foodstuffs and said support material; and separating the foodstuffs from said support material; wherein at least one of said at least one layer comprises an elastomeric polymer layer. 2. The method of claim 1 , wherein said step of heating comprises heating the foodstuffs to a temperature greater than about 100°F. 3. The method of claim 2, wherein said temperature is greater than about 140°F. 4. The method of claim 2, wherein said temperature is greater than about 212°F and less than about 410°F . 5. The method of claim 2, wherein said temperature is greater than about 300°F and less than about 410°F „ 1 6. The method of claim l, wherein the foodstuffs is at a temperature 2 greater than about 100°F when placed into contact with said 3 support material. 1 7. The method of claim 1 , wherein said step of heating comprises 2 placing said foodstuffs in boiling water. l 8. The method of claim 1 , wherein the foodstuffs comprises meat, l 9. The method of claim 1 , wherein the foodstuffs comprises a liquid. l 10. The method of claim 9, wherein said liquid is soup. 1 11. The method of claim l, further comprising storing the foodstuffs 2 after placing the foodstuffs in contact with said support material. 1 12 The method of claim 11 , wherein said storing includes freezing the 2 foodstuffs. 1 13 . The method of claim 12, further comprising thawing the 2 foodstuffs after freezing the foodstuffs. l 14. The method of claim i, wherein less than about 0.5 weight percent of the foodstuffs adheres to said support material after separating the foodstuffs from said support material. 15. The method of claim 1 , wherein said elastomeric polymer layer comprises an elastomeric polymer selected from the group consisting of polyether esters, polyester esters, polyether glycols, polyamide elastomers, nylon-6, nylon-12 and mixtures and copolymers thereof. 16. The method of claim 15, wherein said elastomeric polymer layer comprises an elastomeric polymer selected from the group consisting of butylene/poly(alkylene ether) phthalate, polyester elastomers, and polyamide elastomers. 17 The method of claim 1 , wherein said support material further comprises at least one additive. 18. The method of claim 17, wherein said elastomeric polymer layer comprises at least one additive. 19. The method of claim 18, wherein said additive is selected from the group consisting of ethylene vinyl alcohol, polyvinylidene chloride and SARAN ® 20. The method of claim 18, wherein said at least one additive decreases the oxygen permeability of said polymer. 21. The method of claim 1 , wherein said elastomeric polymer layer comprises at least one elastomeric polymer and at least one additional polymer. 22. The method of claim 21 , wherein said elastomeric polymer and said additional polymer are mixed with one another. 23. The method of claim 21 , wherein said elastomeric polymer and said additional polymer are blended with one another. 24. The method of claim 21 , wherein the additional polymer comprises at least one polymer selected from the group consisting of nylons, copolymers of nylons, polyesters, copolymers of polyesters, polystyrenes, polyethylenes, and copolymers of polyethylenes. 25. The method of claim 21 , wherein said elastomeric polymer layer further comprises at least one additive. 26. The method of claim 25, wherein said at least one additive decreases the oxygen permeability of said polymer. 27. The method of claim 1 , wherein said support material further comprises an additional layer that decreases oxygen and moisture permeability. 28. The method of claim 27, wherein said additional layer comprises polyethylene. 29. The method of claim 1 , wherein said support material comprises a material having at least two layers, wherein at least one layer comprises an elastomeric polymer layer, and at least one layer comprises a polymer or polymer blend layer. 30. The method of claim 29, wherein said at least two layers of said support material are attached to one another by a method selected from the group consisting of lamination and co-extrusion. 31. The method of claim 29, wherein said polymer or polymer blend layer comprises a polymer selected from the group consisting of nylon, polyester, ethylene, vinyl alcohol, polyvinylidene chloride, ethylene vinyl acetate, ethylene base polymers and copolymers. 1 32. The method of claim 29, wherein said polymer or polymer blend 2 layer comprises nylon or a nylon blend. 1 33. The method of claim 29, wherein said support material further 2 comprises at least one tie layer. 1 34. The method of claim 29, wherein said tie layer is ethylvinyl alcohol 2 or ethylene copolymer. 1 35. The method of claim 29, wherein said support material further 2 comprises a third layer. 1 36. The method of claim 35, wherein said third layer comprises 2 polyethylene. i 37. The method of claim 1 , wherein said support material is in the form 2 of a film. 1 38. The method of claim 1 , wherein said support material is in the form 2 of a sheet . i 39. The method of claim 1 , wherein said support material is in the form 2 of a bag. 40. The method of claim 1 , wherein said support material is in the form of a container. 41. The method of claim l, wherein said support material is in the form of a sausage casing. 42. A method for treating foodstuffs, comprising: placing the foodstuffs in contact with an elastomeric support material; storing said foodstuffs; heating the foodstuffs while maintaining contact between the foodstuffs and said elastomeric support material such that the foodstuffs are cooked or reach a desired temperature for consumption; and separating the foodstuffs from said elastomeric support material while the foodstuffs remain at a desired temperature for consumption. 43. A method for treating meat foodstuffs, comprising: placing the meat foodstuffs in contact with an elastomeric support material in the form of a bag, said elastomeric support material comprising a material selected from the group consisting of nylon elastomers, polyester elastomers, and mixtures and copolymers thereof; heating the meat foodstuffs while maintaining contact between the foodstuffs and said elastomeric material; and separating the meat foodstuffs from said support material; wherein less than about 0.5 weight percent of the meat foodstuffs adheres to said support material after the meat foodstuffs is separated from said support material. 44. A method for treating meat foodstuffs, comprising: placing the meat foodstuffs in contact with a support material in the form of a bag, said support material having at least two layers, wherein at least one layer comprises an elastomeric polymer layer comprising a material selected from the group consisting of polyether esters, polyester esters, polyether glycols, polyamide elastomers, nylon-6, nylon-12 or mixtures and copolymers thereof, and wherein at least one layer comprises a polymer or polymer blend layer comprising a material selected from the group consisting of nyion elastomers, polyester elastomers, and mixtures and copolymers thereof; heating the meat foodstuffs while maintaining contact between the foodstuffs and said elastomeric material; and separating the meat foodstuffs from said support material; wherein less than about 0.5 weight percent of the meat foodstuffs adheres to said support material after the meat foodstuffs is separated from said support material.

Inventors: GHERGHEL JASON C, GHERGHEL RADU D, GHERGHEL RADU O, GHERGHEL, JASON, C., GHERGHEL, RADU, D., GHERGHEL, RADU, O.
Applicants: GEM POLYMER CORP, GEM POLYMER CORP.
Application year: 2000
Main classification: B65B55
IPC codes: A23B4