Abstract:
The present disclosure comprises both a self-pressurizing food storage device and method of use. The device defines and presents an enclosed food storage chamber composing an internal air pressure of about 1 psi to about 10 psi above ambient air pressure outside the chamber by providing a geometrically and ergonomically comfortable lid assembly, a food container adapted to mate with the lid assembly, and means for closingly mating them together. No external, detachable pump is required to create the elevated pressure within the food containing chamber.

Description:
RELATED APPLICATIONS  
       [0001]    This application claims its priority of filing date from U.S. Provisional Application No. 60/888,553 entitled SELF PRESSURIZING SHELF LIFE EXTENDER FOR FOOD filed on Feb. 7, 2007 in the United States Patent and Trademark Office. 
     
    
     BACKGROUND  
       [0002]    Common food preservation methods and devices inactivate pathogens and chemicals that cause the food to decay. These include irradiating, drying, canning, heating, pickling, freezing or refrigerating food. Some fresh foods maintain freshness longer by being contained within either an air-tight or an airless container, or by being stored in a container that removes ripening gases, such as ethylene, produced by the food itself. Carbonated beverages are “preserved” by being maintained under air pressure to ensure that the gasses remain in solution until the beverage is consumed. Finally, some foods are preserved by maintaining them under an atmosphere other than ambient air, such as under nitrogen or carbon dioxide. 
         [0003]    Less popular food storage methods and devices include those that subject food to high atmospheric air pressure for varying lengths of time. These methods and devices subject food to atmospheric pressure from about 100-500 pounds per square inch (“psi”) for varying lengths of time. 
         [0004]    Each of the preservation methods or devices above may change or compromise the original texture and flavor of the foods preserved, especially of fresh fruits and vegetables. They also require significant energy energy input. This is especially true for high pressure preservation methods and devices, which are typically used only by factories or manufacturing facilities. 
         [0005]    Recent data suggest that the relatively low pressure of an atmosphere of ambient air, pressurized to about 1 psi to about 10 psi above ambient air pressure, will extend the shelf life of certain foods. Under such low pressure storage conditions, food is not “preserved” for long periods of time, but the shelf life is extended. The texture, color and flavor are largely retained as they are found in the food before low pressure storage. The mechanism of action of low pressure storage is not well known, but it has been proposed that the pressure inhibits the action of pathogens, or that it slows the speed with which the food itself produces agents that contribute to decay. 
         [0006]    Despite some knowledge of the efficacy of low pressure food storage, no consumer device or method currently exist for extending food shelf life under low pressure that does not require detachment after pressurization of an external pump. The U.S. Pat. No. 5,031,785 by Lemme, COMBINATION VACUUM/PRESSURE PUMP AND VALVE STOPPER FOR FOOD OR DRINK CONTAINERS, provides an example of a device using a detachable pump. No self-pressurizing device or method for extending the shelf life of food by storage of food under relatively low pressure has been disclosed heretofore. 
         [0007]    Using a separate and detachable pump is cumbersome, and requires having the pump with you whenever you wish to open the container of stored food, remove a portion of the food to consume, and reseal the remaining food under low pressure. As in the &#39;785 patent by Lemme, use of such a device requires attachment of the pump to a specially adapted valve stopper that mates with the pump, manipulating the pump by sliding the handle of the pump relative to the pump cylinder a sufficient number of times to create a desired vacuum or pressure, and then removing the pump from the valve for storage and future use. This entails several steps which a hungry consumer may not be eager to take. 
         [0008]    Indeed, the majority of food storage products on the market teach away from the device and method of the instant invention. Some popular containers encourage the consumer to push excess air out of the container by “burping” and then sealing the lid, inducing a vacuum. This is directly contrary to the device and method of the disclosure herein. 
         [0009]    For ergonomic and comfortable consumer use, to increase the shelf life of food without requiring external energy input, and to provide this while maintaining a relatively low cost of manufacture, there is a need for a self pressurizing food storage device and method that enables a consumer to store food within an enclosed chamber having an internal air pressure about 1 psi to about 10 psi above external ambient air pressure, and that requires no separate pump or other device to generate such pressurize. 
         [0010]    The disclosed device and method of use disclosed herein support ecological balance and help the environment generally. They require no use of electricity or motor, but instead provide an elegant device that creates a new way to manually create additional pressure of about 1 psi to about 10 psi over ambient air pressure inside the food container. 
         [0011]    No attached pumps or other devices must be used to create the pressure needed. The geometries of the parts of the device and the method of use thereof provides an ergonomically correct and comfortable to use device. The user provides all pressure needed to enclose the food in the disclosed device, and to use the method therefor. 
         [0012]    Increasing the shelf life of food decreases wasted food, such as seasonal produce which may decay faster than the consumer is able to finish the produce purchased, and so provides additional environmental benefits. 
       BRIEF DESCRIPTION  
       [0013]    The present disclosure comprises both a self-pressurizing food storage device and method of use. The device defines and presents an enclosed food storage chamber composing an internal air pressure of about 1 psi to about 10 psi above ambient air pressure outside the chamber by providing a geometrically and ergonomically comfortable lid assembly, a food container adapted to mate with the lid assembly, and means for closingly mating them together. No external, detachable pump is required to create the elevated pressure within the food containing chamber. 
         [0014]    One exemplary embodiment of the device comprises a food container that partially defines a container air space, a lid assembly which partially defines a lid air space, which lid assembly is adapted to sealingly close and mate with the container. The container and lid assembly are adapted to define an airtight chamber when the lid assembly is positioned over the food container in a first position. In this first position, air from the lid air space and air from the container air space may become commingled within the chamber, but are sealingly enclosed there within. In the first position, the commingled air is at about ambient pressure. 
         [0015]    According to the method of the disclosure, and using embodiments of the device described herein, the lid assembly is moved from its first position to a second position in which the lid assembly at least partially overlaps the container. At this second position, air within the chamber is pressurized to about 1 psi to about 10 psi above ambient pressure outside the chamber because the volume of the air within the chamber decreases while its mass remains the same. After positioning the lid assembly in its second position, this second position is maintained by a closure assembly. 
         [0016]    Closure assemblies according to the disclosure may comprise at least one: bayonet closure, over-center latch, pivotally attached lever, or some other closure assembly known in the art. Closure assembly is geometrically configured to provide sufficient leverage to enable a consumer to urge the lid assembly into its second position ergonomically and manually, and to thereby create an internal air pressure within a pressurized chamber according to this disclosure of about 1 psi to about 10 psi over external ambient pressure. 
         [0017]    Proper pressure within the device is maintained in at least one exemplary embodiment that comprises a valve assembly positioned in the lid assembly. 
         [0018]    In an exemplary embodiment, the device and method comprise a potassium permanganate impregnated zeolite within the food container, which zeolite absorbs ethylene gas produced by the contained food. Some produce, such as bananas, naturally produce ethylene, which gas quickens the ripening and then the decay of the fruit. Removal of ethylene in combination with low pressure lengthens the shelf life of foods that emit ethylene. 
     
    
     
       DRAWINGS 
         [0019]      FIG. 1  is an exploded perspective view of an exemplary embodiment of a device of the disclosure; 
           [0020]      FIG. 2  provides three views of an exemplary method of use of the disclosures; 
           [0021]      FIG. 3A  is a perspective view of an exemplary embodiment of a device of the disclosure; 
           [0022]      FIG. 3B  is a top plan view of an exemplary embodiment of a device of the disclosure; 
           [0023]      FIG. 3C  is a side elevation view of an exemplary embodiment of a device of the disclosure; 
           [0024]      FIG. 3D  is a sectional view of a device of an exemplary embodiment viewed along the axis defined in  FIG. 3C ; 
           [0025]      FIG. 4A  is a side elevation view of an embodiment of an exemplary device of the disclosure; 
           [0026]      FIG. 4B  is a side sectional view of an embodiment as shown in  FIG. 4A  of an exemplary device of the disclosure. 
           [0027]      FIG. 5  is a partial sectional view of an exemplary embodiment of a device of the disclosure; 
           [0028]      FIG. 6  is a partial sectional view of an exemplary embodiment of a device of the disclosure; 
           [0029]      FIG. 7  provides three partial side sectional views of an exemplary embodiment of a device of the disclosure; 
           [0030]      FIG. 8A  is a top plan view of an exemplary embodiment of a device of the disclosure; 
           [0031]      FIG. 8B  is a side sectional elevation of an exemplary embodiment of a device of the disclosure; and 
           [0032]      FIG. 8C  is a side sectional elevation of an exemplary embodiment of a device of the disclosure. 
       
    
    
     DETAILED DESCRIPTION  
       [0033]    A device and method of use therefor of extending the shelf life of food comprising an airtight food storage chamber of formerly ambient air pressurized to about 1 to about 10 pounds per square inch above ambient pressure, the chamber defined by closingly mating a food container and a lid assembly, wherein the ambient air therein is pressurized by moving the lid assembly relative to the container from a first position to a second and mated position. 
         [0034]    An exemplary embodiment of the device  10  is illustrated at  FIG. 1 .  FIG. 1  discloses a food container  20 , a lid assembly  30 , at least one closure assembly  40 , a valve assembly  34 , a zeolite holder  60  and zeolite viewing window  92 , and at least one seal  26  mounted on at least one rim  28  of the container  20 . 
         [0035]    Valve assembly  34  comprises at least one valve  34   a,    FIG. 1 , calibrated to release pressure from within the compressed air space  52  should that pressure exceed about 10 psi. Increased pressure may result from, for example, food  22  within container  20  creating gasses or causing production of gas creating agent. 
         [0036]    Valve assembly  34  can be calibrated to a smaller range of pressures within the possible range of about 1 psi to about 10 psi, depending on optimum storage pressure for one or more types of food being stored. 
         [0037]    Valve assembly  34  may comprise at least one valve configured to release vacuum created within chamber  50 ,  52  when device  10  is opened, namely when lid assembly  30  is moved from its second position to its first position, and then removed from contact with food container  20 . As in  FIG. 1 , mushroom valve  34   a  is adapted to release excess pressure within chamber  52 , while mushroom valve  34   b  is adapted to release any vacuum formed when lid assembly  30  is being moved apart from food container  20 . 
         [0038]    Referencing an exemplary embodiment of  FIG. 1 , closure assembly  40  illustrated therein comprises a pair of levers  44 , catch rings  42  mounted thereon, lever arms  46  adapted to hingedly attach levers  44 , and catch arms  21  over which catch rings  42  fit and under which catch rings  42  latch. Closure assembly  40  is configured to urge and move lid assembly  30  from its first position to its second position, when manipulated by a user, thereby creating a low pressure food storage chamber  52 . The length of levers  44  may vary depending upon the amount of mechanical leverage required to ergonomically and easily achieve lid assembly  30  second position. These closure assemblies may, in exemplary embodiments, be adapted to reversibly latch lid assembly  30  in its second position. 
         [0039]    The lid assembly  30  and food container  20  in this and other exemplary embodiments disclosed herein are geometrically configured to create air pressure from about 1 psi to about 10 psi within chamber  50 ,  52  without the use of an external pump. 
         [0040]    Lid assembly  30  and container  20  are geometrically proportioned to generate from about 1 psi to about 10 psi over ambient air pressure when lid assembly  30  comprises its second position. Should particular foods have optimum storage pressure of 3 psi above ambient pressure, for example, the volume of chamber  50  may be adapted to permit a user to move lid assembly  30  from a first to a second position without use of a separate or removable device. Such closure assembly may also comprise a bayonet closure (not shown). In a preferred embodiment comprising a bayonet closure, the rotation of the lid assembly  30  relative to the food container  20  is less than 360 degrees of rotation. 
         [0041]    In an exemplary embodiment, optimal chamber pressure is from about 1 psi to about 10 psi above ambient pressure. In another exemplary embodiment, optimal chamber  52  pressure is from about 3 psi to about 5 psi above ambient pressure. To achieve different ambient pressures or ranges, valves with different cracking pressures may comprise valve assembly  34 . 
         [0042]    Certain fresh foods, for example bananas, naturally produce ethylene, which gas quickens the ripening and then the decay of the fruit. Removal of ethylene from a storage container using zeolite, in combination with low pressure storage, further lengthens the shelf life of foods that emit ethylene. 
         [0043]    In an exemplary embodiment illustrated in  FIGS. 1 and 3 , the device and method comprise a potassium permanganate impregnated zeolite within food container  50  that absorbs ethylene gas produced by the contained food. Zeolite is provided in a sachet (not shown) comprising an air and water vapor permeable membrane. The sachet may be suspended within pressurized chamber  52  from zeolite holder  90 . Holder  90  is removeable, so that zeolite sachets may be replaced as necessary. 
         [0044]    Zeolite impregnated with potassium permanganate is a purple or lavender color when it is “fresh” or able to absorb ethylene, but turns brown when it is ethylene saturated. A user might therefore prefer knowing whether a fresh sachet needs to replace a saturated one, and may determine the status of the zeolite absorbing capacity while device of the disclosure  10  is in use. Transparent window  62  is positioned in lid assembly  30  to enable a user to view the color of the zeolite sachet from outside storage device  10 . To replace a sachet, the user may then open device  10 , replace a used zeolite sachet with a new one, then repressurize device  10 . 
         [0045]    An exemplary embodiment of the method of using the device is illustrated at  FIG. 2 . In  FIG. 2A , the food container  20  holds food to be stored that was previously placed in the container  22  (food not claimed, included for illustrative purposes only) and ambient pressured air present in a partially defined container air space  24 . The lid assembly  30  comprises a partially defined lid air space  32  in which air is at ambient pressure. 
         [0046]    After food is placed in the container  20 , the lid assembly  30  and container  20  are arranged in a first position, as illustrated at  FIG. 2B , and now comprise a combined air space  50 . At this first position, air within the air space  50  is at about ambient air pressure. 
         [0047]    In  FIG. 2C , lid assembly  30  is then closingly mated with the container  20 , thereby changing the volume of the air space to a compressed air space  52 . The air within the compressed air space  52  thereby becomes pressurized to about 1 psi to about 10 psi above ambient pressure. As one exemplary embodiment of the geometrical proportions of lid assembly  30  to container  20  should a desired pressure within the chamber  52  comprise about 3 psi above ambient pressure, lid assembly  30  is adapted to comprise lid air space of about 15-20% of container air space  32 . 
         [0048]    In another exemplary embodiment of the invention,  FIGS. 4 and 5 , the lid assembly comprises at least flexible bellows  31 . Lid bellows  31  may comprise domed section  31   a;  annular convex portions  31   b,    31   h;  annular concave portions  31   c,    31   e,    31   g;  annular cone portion  31   d;  and cylindrical portion  31   f.  The centers of lid bellows portions  31   a  through  31   h,  inclusive, line up along a common center line L 1 -L 2 . Domed section  31   a  has a the smallest radius of the portions of bellows  31 . Remaining portions,  31   b,    31   c,    31   d,    31   e,    31   f,  and  31   g,  each have incrementally larger radii, with annular convex portion  31   h  comprising the largest radius of bellows  31 . 
         [0049]    When bellows  31  is in its first or extended position,  FIGS. 4A and 4B , bellows portions  31   a - 31   h  may be said to be oriented “up.” When bellows  31  is compressed into its second position,  FIG. 4C , annular bellows portions  31   a - 31   h  are configured and adapted to fold in on each other in a modified “accordian” until bellows  31  is in its second position. When bellows  31  is fully compressed in its second position, some of bellows  31  portions remain in their “up” configuration, namely  31   a,    31   b,    31   c,    31   d,    31   g  and  31   h,  while remaining bellows portions,  31   e  and  31   g,  become oriented “down” relative to their original position. Areas of connection between each of bellows portions  31   a - 31   h  are functionally living hinges. 
         [0050]    The specific pattern of bellows portion folding may vary between embodiments, depending upon the degree of pressure within the chamber desired. A smaller volume  52  results when a greater number of bellows  31  portions become oriented “down” in the lid assembly&#39;s second or compressed position. 
         [0051]    By virtue of common alignment center along line L 1 -L 2 , sequentially sized radii, lid bellows portions  31  are configured to fold in a vertical line L 1 -L 2  that includes the center of each portion  31   a  through  31   h,  inclusive, when a pivotally attached arm  60  is moved from its open, first position to its latched, second position. 
         [0052]    Bellows  31  comprises a first, extended position, wherein portions  31   a  through  31   h,  inclusive, are “up”. Pressurization of air within chamber  50  may be effected by collapsing bellows  31  to its second position. Such collapse may result from a user moving a hinged lever arm  60  from first position,  FIG. 5 , to second position,  FIG. 6 . 
         [0053]    Hinged arm  60 ,  FIGS. 4 ,  5  and  6 , comprises arm bar  63 , inner push rim  62 , outer insert rim  67 , latch keeper  65 , tab arm  64  and tab  66 . Arm  60  is attached by hinge  29  to bellows lid assembly  31  in one or more embodiments illustrated, but may be hingedly attached to container  20  instead. Outer insert rim  67  may comprise at least one stabilizer member  61 , shown in cross-section at  FIGS. 4B and 4C  (as open circles). The at least one stabilizer member  61  may comprise one or more connected loops or a plurality of discontinuous stabilizing members of the insert rim  67 . 
         [0054]    According to an exemplary method of the disclosure, a user moves hinged arm  60  from its first position,  FIG. 5 , to its second position,  FIG. 6 . When the hinged arm  60  is positioned at its first position, the lid bellows  31  is also positioned at its first position. Similarly when the hinged arm  60  is moved to its second position, the lid bellows  31  is compressed into its second position,  FIG. 6 . 
         [0055]    When a user moves the arm  60  from its first to second position, inner rim  62  partially entraps and encloses lid bellows portion  31   a,  and thereby maintains collapse of bellows  31  within container rim  21 . At least one hinge attaching arm  60  to lid assembly  30  may comprise any hinge known and used in the art, such as for example, a living hinge. 
         [0056]    The amount of force a user must exert to move lid assembly to its second position is proportional to the amount of pressure desired inside the chamber  50  and the size and dimensions of the chamber  52 . The geometry of closure assembly employed in an exemplary embodiment of the device  10  may depend therefrom. For smaller containers, a bayonet closure or over center latch assembly works easily as a closure assembly. For larger containers, closure assembly  40  that employs lever arm  44  attached to container  20  by hinge  29  may be preferred. 
         [0057]    In a still further exemplary embodiment, a lever that compresses the bellows may be completely separate from any closure that maintains the lid assembly in its second position relative to the container. A latch assembly adapted to maintain a lid assembly may be independent of any lever assembly or closure assembly. 
         [0058]    Referring now to  FIG. 7 , where are illustrated embodiments of exemplary, but not limiting, latch assemblies of device  10 .  FIG. 7A  illustrates lever arm  60  comprising an inset, slidable latch  40 . Leading edge  41  of latch  40  is angled to catch under rim  72 . Latch  40  is slidably disposed within or upon arm  60 , and a user may engage or disengage leading edge  41  with rim  72 . Further illustrated is compressible seal  70  mounted on rim  21 . 
         [0059]      FIG. 7B  illustrates a cross section of at least one stabilizing member  72  of rim  72 . 
         [0060]      FIG. 7C  illustrates hinged latch  82  hingedly attached to a lid assembly  30 . An aperture  84  defined by latch  82  captures keeper  80  when latch  82  is positioned thereupon, the keeper  80  extending outwardly from rim  21  through aperture  84 . 
         [0061]    An exemplary embodiment is illustrated in  FIG. 8  of a non-round device  10 .  FIG. 7A  illustrates exemplary members comprising a bellows assembly  31 . As illustrated in  FIG. 7B , slidable closure assembly  40  is adapted for catching leading edge  41  under rim  72 . A zeolite viewing window (not shown) may comprise the bellows lid assembly  31 . Closure assembly  40  may be slidingly disposed upon top bellows portion  31   a  of bellows lid assembly  31 , or may be disposed upon a lever arm  60 . 
         [0062]      FIG. 8B  illustrates at least one snap fit tab and slot assembly  74  adapted to latch top assembly  31  to food container  20 . 
         [0063]      FIG. 8C  illustrates hinged lever assembly  60  comprising at least one inner push rim  62  adapted to capture top bellows portion  31   a.  While  FIG. 8  illustrates one non-round embodiment of device  10 , the methods of compressing the lid bellows assembly  31  by closure assembly  60  are identical. 
         [0064]    While the device and method of exemplary embodiments have been illustrated and described in what are considered to be practical and preferred embodiments, it will be recognized that many variations are possible and come within the scope thereof. The appended claims therefore being entitled to a full range of equivalents.