JP2007528328A - Vacuum skin packaging - Google Patents

Abstract

  Disclosed are packaging and methods for packaging fresh food products such as animal meat, fish, chicken, vegetables or other food. The package includes a vacuum skin package that includes a film having specific packaging gas permeability requirements and a skeletal element in which the article to be packaged is held.

Description

  The present invention relates to packaging, and relates to packaging containing animal meat, fish, chicken, vegetables or other food, and a method of packaging food using this improved packaging.

  Perishable goods are susceptible to exposure to and exposure to microorganisms such as bacteria and mold by contact with airborne organisms or contact with organisms on the surface. Contamination can promote spoilage, form toxins, and have other harmful effects. Therefore, it is desirable to protect food from contact with microorganisms. Packaging of such fresh food products in gas impermeable materials such as foils, paperboard and oxygen barrier films can provide a barrier to microbial contamination.

  However, anaerobic organisms such as Clostridium botulinum produce powerful toxins that are causative agents of botulism, a very toxic and dangerous food poisoning. Since Clostridium botulinum is an anaerobic organism, gas impermeable materials such as foils, paperboard and oxygen barrier films are not suitable for packaging foods that are highly susceptible to botulinum toxin formation. Clostridium botulinum spores are heat resistant and it is impossible to kill spores by simply heating the food. In order to minimize the growth of Clostridium botulinum, it is necessary to provide a package where the surface of the fresh food product is in contact with oxygen. Thus, fresh fish packaging must provide a physical barrier to microorganisms and other contamination and must provide oxygen permeability.

  Clostridium botulinum contamination is a particular problem in fresh fish. Traditionally, fresh fish have been sold in ice-cold containers open to the atmosphere to minimize the growth of botulinum and the resulting toxin formation. In the past, such sales methods have been limited to relatively small geographic areas near the waters where the fish were caught. For wider distribution, fish have been conventionally frozen.

  With current distribution methods, inland consumers are increasingly demanding to eat fresh fish rather than frozen fish. However, it is difficult to package fresh fish so as to minimize the risk of botulism. Clostridium botulinum growth and toxin formation can result from misuse of time / temperature during processing, storage, and distribution. In some cases, dangerous conditions can occur even at temperatures> 70 ° F for as little as 2 hours, 50-70 ° F for 11 hours, 42-50 ° F for 2 days, 37.9-41 ° F for 7 hours. Can happen in days.

  General vacuum packaging suppresses the growth of normal spoilage organisms, but if done so under conditions that block oxygen, the growth of Clostridium botulinum is not suppressed. Thus, vacuum packaging under oxygen blocking conditions increases the likelihood that botulinum toxin is produced and is unacceptable to consumers.

  Packaging of meat, fish, chicken, vegetables or other foods does not affect the appearance or shelf life of the package, is relatively simple and inexpensive to manufacture, and further protects the package from damage. It is also desirable to provide a relatively long shelf life of the packaged product in packaging that is sufficiently robust.

  Vacuum skin packaging is a common method for packaging many foods, in which the food is packaged closely with the packaging material, and virtually all air is excluded. In order to increase the rigidity of the packaging so that it can be better promoted, the food is placed in a tray or on a paperboard mount. In some cases, the package itself, such as frozen fish, is sufficiently hard and no other hard packaging elements are required.

  In order to increase the shelf life and shelf life of the contents, packaging containing a specific gas is also known. In general, these packages are made from a plastic material that provides at least a partial barrier to unwanted gases. The plastic material is a material that escapes gas generated in the package. Other known plastic materials allow certain gases to permeate and improve the shelf life of the package. For example, U.S. Pat. No. 4,685,274; U.S. Pat. No. 4,840,271; U.S. Pat. No. 5,025,611; U.S. Pat. No. 5,103,618 and See U.S. Pat. No. 5,115,624. However, the packages disclosed therein have a limited volume of gas that can be held in the headspace.

  Some foods, such as fresh fish, must be packaged with a film with a certain gas permeability to ensure food safety to prevent the growth of anaerobic bacteria. In the case of fresh fish, the use of substrates such as paperboard, bases or trays is unacceptable because the substrate prevents oxygen from contacting the fish.

The guidelines of the US Food and Drug Administration (FDA), defines a "considered to be oxygen permeable packaging having 10,000cc / m ^2/24 hours or more OTR". Such OTR cannot be achieved with typical foam trays used for packaging foods such as fresh meat.

  The FDA guidelines also point out that "the use of oxygen permeable packaging will not compensate for oxygen exchange limitations caused by the implementation of packaging in deep containers from which air is squeezed out". If the FDA guidelines on oxygen permeability are not met, a Hazard Analysis of Critical Control Points (HACCP) plan, a quality assurance agreement widely used in the food industry must be established. Temperature monitoring is required and a time / temperature index (TTI) must be attached to the shipping container. Temperature control and monitoring can be done during the distribution chain, but it is impractical to do it after the packaged fresh fish has been sold to the consumer. The combination of time and temperature at which dangerous levels of botulinum toxin can be produced can easily occur during consumer handling after the packaged fresh fish is sold.

  Thus, vacuum skin packaging with specific gas permeability, as well as skeletal elements that hold the package in it, thereby providing sufficient rigidity to the package but not in contact with the contents (ie the package) It is desirable to develop. The food only comes into contact with a gas permeable film that brings sufficient oxygen into contact with the surface of the food. If oxygen in the headspace of the package is available to suppress the growth of anaerobic organisms, the package can be made of a gas impermeable material. However, it is difficult to provide sufficient oxygen in the headspace of such a package to provide long-term protection against anaerobic growth.

The present invention includes a vacuum skin packaging capable of containing fresh food products, the packaging comprising: (a) a first flexible web of gas permeable skin packaging plastic material; One or more rigid or semi-rigid framework elements that are not in contact with fresh food products; and (c) a second flexible web of gas permeable skin-wrapped plastic material; The flexible web and the second flexible web are hermetically sealed to contain the fresh food product. Packaging can either contain a gas permeable plastic material having 10,000cc / m ^2/24 hours or more oxygen transmission rate of (OTR), or produced therefrom.

  The present invention includes (a) placing a fresh food product on the first flexible web of gas permeable skin-wrapped plastic material in contact with the inner surface of the first flexible web; (b) fresh food. Installing one or more rigid or semi-rigid framework elements in contact with the inner surface of the first flexible web so as to surround the product but not in contact with the perishable food product; (c) a second flexible Gas permeable on the fresh food product and the one or more skeletal elements such that the inner surface of the flexible web contacts the fresh food product, the one or more rigid or semi-rigid skeleton elements and the inner surface of the first flexible web. Installing a second flexible web of skin wrapping plastic material; (d) sealing the first flexible web and the second flexible web together to provide one or more skeletal elements and fresh food products; A method of packaging food, comprising: No.

  Alternatively, the method comprises (a) placing a fresh food product on the first flexible web of gas permeable skin wrapping plastic material in contact with the inner surface of the first flexible web; (B) a second flexible web of gas permeable skin wrapping plastic material on the fresh food product such that the inner surface of the second flexible web is in contact with the inner surface of the fresh food product and the first flexible web. (C) surrounding the fresh food product but in contact with the outer surface of the first flexible web and optionally in contact with the outer surface of the second flexible web so as not to contact the fresh food product. In a state, installing one or more rigid or semi-rigid framework elements; (d) sealing the first flexible web and the second flexible web together to contain the fresh food product; May be included.

  The term micron (μ) is equal to 1/1000 of a millimeter (mm). A micron is sometimes called a micrometer (μm). The term mill is equal to 1 / 1000th of an inch or 25.4 microns.

  The term “inner surface” means the surface of a film or packaging web that comes into contact with a packaged article and is formed after it is formed. The inner surface of the packaging web is either the food contact surface or the sealant surface because part of the surface of the surface is in contact with the food and the other part of the surface is in the area where the seal is formed. Also plays a role.

  The term “outer surface” means the side of the film or packaging web that does not contact the package and provides the outer surface of the package after it has been formed.

  Fresh food products are animal meat, fish, chicken, vegetables or a combination of two or more thereof, but other types of food products such as other ingredients can be packaged if desired.

Packaging web can preferably be prepared from the film of the thermoplastic composition having a 10,000cc / m ^2/24 hours or more OTR.

  The OTR of a film depends on the thickness of the film and the intrinsic permeability of the composition. The permeability depends on factors such as temperature, relative humidity, and the pressure of the gas striking the film. In general, OTR is calculated using standard conditions normalized to 23 ° C., 50% relative humidity, and 1 atmosphere.

  It is also desirable to use a film that does not stretch (ie, creep resistant) with the weight of the package to improve the appearance of the package for retail display.

  In a first embodiment of this aspect of the invention, the one or more framework elements are in contact with the inner surface of the first flexible web and in contact with the inner surface of the second flexible web. Between the first flexible web and the second flexible web so as not to contact; the first flexible web and the second flexible web include one or more framework elements and Sealed together to contain fresh food products.

  In a second embodiment of this aspect of the invention, the one or more framework elements are in contact with the outer surface of the first flexible web and optionally in contact with the outer surface of the second flexible web; Surrounds the fresh food product but does not contact the fresh food product; the first flexible web and the second flexible web are sealed together to contain the fresh food product.

  Films suitable for packaging webs are metallocene polyethylene (mPE) with a high OTR (especially grades having a density of less than 0.91 g / cc, more particularly grades having a density of less than 0.89 g / cc). May be included.

The metallocene polyethylene (mPE) used in the present invention is any such commonly known in the art, provided that its oxygen permeability is high enough to provide the requisite permeability required for the packaging web. It can be polyethylene. More specifically, the metallocene polyethylene should have a density of less than 0.91 g / cc, preferably less than 0.89 g / cc, at which the standardized OTR _n at 23 ° C. and 50 ° C. relative humidity is About 12,400 cc-mil / m ² · day · atmosphere, preferably over 20,000 cc-mil / m ² · day · atmosphere. These mPEs are optionally other low crystalline polyolefins or amorphous polyethylenes (low density polyethylene, LDPE; linear low density polyethylene, LLDPE; other, provided that the blend retains significantly higher permeability. mPE etc.). In order to improve processing, the composition may further comprise an ethylene copolymer such as an ethylene / vinyl acetate copolymer or an ethylene / alkyl (meth) acrylate copolymer. The composition may further comprise an ethylene / acid copolymer that is at least partially neutralized with an inorganic cation (ie, an ionomer).

For example, having the OTR _n exceeding density and about 20,000cc- mil / m ² · day · air pressure of less than 0.89 g / cc, mPE film thickness of 2 mil, 10,000Cc- mil / m ^2/24 Will have an OTR of time.

  Compositions containing ethylene copolymers that are at least partially neutralized with cations (ionomers) and modified with organic acids are also suitable for producing films with high oxygen permeability. These compositions are described in detail in International Patent Application Publication No. WO 03/089240. This publication also describes a multilayer film with high oxygen permeability comprising at least one layer of modified ionomer and at least one layer of mPE.

  The ethylene copolymer is about 5 to about 50 weight percent, or about 10 to about 19 weight percent of a polar monomer such as acrylic acid, alkyl acrylic acid, or alkyl acrylate, or a combination of two or more thereof, based on the total weight of the ethylene copolymer. Or a polymer that may contain repeating units derived from 12 to 15 weight percent (wt%). Alkyl groups can contain up to about 20 carbon atoms, such as methyl, ethyl, butyl, isobutyl, pentyl, hexyl, and combinations of two or more thereof.

  The ethylene copolymer can be any comonomer such as carbon monoxide, sulfur dioxide, acrylonitrile; maleic anhydride, maleic diester, (meth) acrylic acid, maleic acid, maleic monoester, itaconic acid, fumaric acid, fumaric monoester. , Salts of these acids, glycidyl acrylate, glycidyl methacrylate, and glycidyl vinyl ether, and combinations of two or more thereof, may be included up to 35% by weight.

  The acid sites of the ethylene copolymer are neutralized with cations to produce ionomers. Neutralization, for example, using metal ions in the range of about 0.1 to about 100, or about 10 to about 90, or about 20 to about 80, or about 20 to about 40% based on the total carboxylic acid content. It is. The metal ion can be monovalent, divalent, trivalent, multivalent, or a combination of two or more thereof.

  The ionomer can also be a blend of ionomers, such as ethylene (meth) acrylic acid copolymer, having a neutralization greater than 20% to achieve the desired degree of neutralization.

  Examples of ethylene copolymers include, but are not limited to, ethylene / methyl acrylate (EMA), ethylene / ethyl acrylate (EEA), ethyl acrylate (EA), ethylene / butyl acrylate (EBA), ethylene / isobutyl acrylate / methacrylic acid, ethylene / Methyl acrylate / maleic anhydride, ethylene / butyl acrylate / glycidyl methacrylate (EBAGMA) and ethylene / butyl acrylate / carbon monoxide (EBACO), and butyl acrylate (BA).

  Examples of commercially available ethylene copolymers have the trademarks Surlyn (R), Nucre (R), Appel (R), Bynel (R), Elvaloy (R), and Elvax (R), E. I. Examples include ethylene copolymers commercially available from du Pont de Nemours and Company (DuPont), Wilmington, Delaware.

  The method of manufacturing the film, multilayer film, and corresponding film structure can be any method as practiced in the art. Films and film structures, as such, generally include orientation (uniaxial or biaxial) by various methods (eg, blown film, bubble technology, mechanical stretching, etc., or laminating methods). Extrusion molding, coextrusion molding and the like can be performed. Various additives commonly used in the art are included in each film layer, such as a tie layer, provided that its presence does not substantially change the properties of the permeable film or film structure. Can exist. Such additives include antioxidants and heat stabilizers, ultraviolet (UV) light stabilizers, pigments and dyes, fillers, antiskid agents, plasticizers, other processing aids, and the like.

  The package includes two gas permeable film webs. The two film webs are generally two individual sheets of film. The web has the same composition and appearance. As an alternative, one web is different from the other web. For example, one web can be transparent to make the package visible, and the other web is opaque and / or colored to provide a background. Designs, logos, alphanumeric characters can be printed on one or both of the webs to provide a pleasing appearance to the packaging and / or to provide information to the consumer. A single web of film can be folded onto itself to provide two overlapping webs, or the two overlapping portions of the tube provide a film corresponding to the two webs Those skilled in the art will appreciate that the tube can be formed.

  The packaging can be made from two webs of gas permeable packaging film. The package is formed by placing the contents of the package between the film webs, applying a vacuum and then bonding the perimeters of the two webs together, preferably by heat sealing. The perimeter of heat-sealed packaging is generally known in the art, and as is practiced, the first and second webs of polymer film are overlaid and then directly heat sealed or intervened with each other. They can be obtained by indirectly heat-sealing them by using three polymer films.

  Rigid or semi-rigid framing elements are manufactured from a thermoplastic composition such as paperboard or polyester.

  The skeletal elements are sized so that they surround the item to be packaged but do not contact the item. For example, but not limited to, the skeletal element defines a packaging area that is about 10 to about 30 cm in length and about 10 to about 30 cm in width in which items to be packaged are placed. Although generally described herein with respect to a rectangular region, other shapes can be envisaged.

  The skeleton elements can be molded, embossed, embossed, etc. to provide a pleasing appearance of the package. The framework elements can also be printed with designs, logos, alphanumeric characters, etc. to provide a pleasing appearance on the packaging and / or to provide information to the consumer.

  One embodiment of the skeletal element includes a generally flat sheet of paperboard or thermoplastic composition formed to provide a concentric opening at the shaped peripheral edge. This embodiment is similar to the mat used for the picture frame, generally in contact with the flexible packaging web on the same plane. The shaping periphery is, for example, a rectangle. The surrounding corners are either square or rounded. The concentric openings are similarly shaped with smaller dimensions so as to provide an equally sized edge around the shape of the framing element. As an alternative, the opening can be shaped differently from the surrounding shape so as to provide an edge having different dimensions depending on the orientation of the opening relative to the surrounding. Shapes other than rectangles can be used around and / or concentric openings. The thickness of this embodiment of the skeletal element is from about 0.5 mm to about 3 mm. The edge dimensions are from about 1 cm to about 3 cm, or more, depending on the shape and size considered for the surrounding and concentric openings.

  Alternative embodiments of the skeletal elements include one or more generally flat paperboard or thermoplastic composition strips formed such that they form a shaped peripheral edge portion. The strip of this embodiment is generally in the same plane and contacts the flexible packaging web. For example, using two strips with a space between them, providing dimensions on the other two sides (eg, along the short dimension of the rectangle), along with the distance of the space between the strips Two sides are defined (eg, the side along the long dimension of the rectangle). As an alternative, the strip defines other parts around the packaging area. For example, it forms a part of a shaping perimeter that includes a corner and two adjacent sides. The strip forms part of a shaped perimeter that includes one side, two corners, and two adjacent side portions. The strip can also be formed to provide a shape other than a rectangle. For example, the strip can be formed as an arc that provides a curved shape. The strip is about 1 cm to about 3 cm wide or more, depending on the shape and size considered for the packaging area.

  An alternative embodiment of the skeletal element includes a strip of paperboard or thermoplastic composition formed to define a packaging area generally coplanar with the packaging web, but perpendicular to the surface of the packaging web. It has considerable dimensions in various directions and also defines the packaging volume.

  As disclosed above, the skeletal element is positioned or placed between two flexible packaging webs to define a packaging area and sealed within the packaging. The packaging according to this embodiment comprises (a) placing a fresh food product on the first flexible web of gas permeable skin wrapping plastic material in contact with the inner surface of the first flexible web; ) Installing one or more rigid or semi-rigid framework elements in contact with the inner surface of the first flexible web so as to surround the fresh food product but not in contact with the fresh food product; 2 on the fresh food product and the one or more skeleton elements such that the inner surface of the flexible web contacts the fresh food product, the one or more rigid or semi-rigid skeleton elements and the inner surface of the first flexible web. Installing a second flexible web of gas permeable skin wrapping plastic material; (d) a first flexible web and a second flexible so as to receive one or more framework elements and fresh food items; Sealing the web; It is possible to elephants.

  Steps (a) and (b) can be performed such that (a) is performed prior to step (b) and (b) is performed prior to or simultaneously with step (a).

  In a second embodiment of the packaging of the present invention, the skeletal element is positioned or placed in contact with one or both outer surfaces of the packaging web and is on the outer surface of the package.

  An example of this second embodiment is that a skeletal element comprising a generally flat sheet of paperboard or thermoplastic composition having a shaped peripheral edge with concentric openings therein is one outer surface of the gas permeable web. Includes packaging that is attached to. The skeletal element is attached by means such as, for example, hot melt adhesive or heat sealing.

  Alternatively, the skeletal element comprises a generally flat sheet of paperboard or thermoplastic composition that can be folded around a gas permeable packaging web to provide a shaped perimeter with openings. . In this embodiment, a portion of the skeleton element is attached to the outer surface of the first packaging web and the second portion of the skeleton element is attached to the outer surface of the second packaging web.

  The packaging according to this embodiment comprises (a) placing a fresh food product on the first flexible web of gas permeable skin wrapping plastic material in contact with the inner surface of the first flexible web; ) Placing the second flexible web of gas permeable skin wrapping plastic material on the fresh food product such that the inner surface of the second flexible web is in contact with the fresh food product and the first flexible inner surface; (C) surrounding the fresh food product but in contact with the outer surface of the first flexible web and optionally in contact with the outer surface of the second flexible web so as not to contact the fresh food product; Producing one or more rigid or semi-rigid framing elements; (d) sealing the first flexible web and the second flexible web to contain the fresh food product; Can do.

  Since the skeletal element is external to the package, stage (c) regarding the installation of the skeletal element is performed before stage (a), before stage (b), before stage (d), or after stage (d). Or at the same time as one of steps (a) or (b).

Claims (8)

  (A) a first flexible web of gas permeable skin-wrapped plastic material; (b) one or more rigid or semi-rigid framework elements that surround the fresh food product but do not contact the fresh food product; and (c) A vacuum skin wrap for containing fresh food products, wherein the first flexible web and the second flexible web are fresh. Vacuum skin packaging, sealed together to contain food products. The gas permeable plastic material has a 10,000cc / m ^2/24 hours or more of OTR, packaging according to claim 1.   The packaging of claim 2, wherein the gas permeable plastic material comprises metallocene polyethylene.   The gas permeable plastic material comprises an ethylene / acid copolymer that is at least partially neutralized with at least one cation, modified with at least one organic acid, or both. 2. Packaging according to 2.   The one or more skeletal elements surround the fresh food product in contact with the inner surface of the first flexible web and in contact with the inner surface of the second flexible web, but in contact with the fresh food product Not between the first flexible web and the second flexible web; the first flexible web and the second flexible web comprising the one or more framework elements And the packaging of claim 2 sealed together to contain fresh food products.   The one or more skeletal elements are in contact with the outer surface of the first flexible web and optionally in contact with the outer surface of the second flexible web and surround the fresh food product, 3. A package according to claim 2, wherein the first flexible web and the second flexible web are sealed together to contain the fresh food product.   (A) placing a fresh food product on the first flexible web of gas permeable skin wrapping plastic material in contact with the inner surface of the first flexible web; (b) surrounding the fresh food product; Installing one or more rigid or semi-rigid skeleton elements in contact with the inner surface of the first flexible web so as not to contact the fresh food product; (c) of the second flexible web; Gas permeable on the fresh food product and the one or more skeletal elements such that an inner surface contacts the fresh food product, the one or more rigid or semi-rigid skeleton elements and the inner surface of the first flexible web. Installing a second flexible web of skin wrapping plastic material; and (d) sealing the first flexible web and the second flexible web together to provide the one or more framework elements and Containing fresh food products; , A method for packaging food products.   (A) placing a fresh food product on the first flexible web of gas permeable skin wrapping plastic material in contact with the inner surface of the first flexible web; (b) the second flexible web; Placing a second flexible web of gas permeable skin-wrapped plastic material on the fresh food product such that the inner surface of the food product contacts the fresh food product and the inner surface of the first flexible web; (c) One or more surrounding the fresh food product but in contact with the outer surface of the first flexible web and optionally in contact with the outer surface of the second flexible web so as not to contact the fresh food product Providing a rigid or semi-rigid skeleton element; and (d) sealing the first flexible web and the second flexible web together to receive a fresh food product. How to package goods.