Abstract:
An atmosphere controlled, resealable foodstuff container includes a base tray and a cover. The cover and base tray are constructed of a substantially gas impermeable material. The cover and base tray include resealing members. When connected, the cover and base tray define a generally enclosed and sealed interior space for foodstuffs. The container includes at least one atmosphere control member, such as a membrane, which controls the flow of gases through an opening in the container. The member may be located over a recessed opening in the cover to permit the containers to be stacked without gas flow interference. A label extends over the recess, thus obscuring the membrane from view to the purchaser without affecting the membrane atmosphere control function. The base tray may be opaque for use as a serving tray and the cover transparent to permit viewing of the product.

Description:
FIELD OF THE INVENTION 
   The present invention relates to packaging for fresh foodstuffs such as fruits and vegetables. 
   BACKGROUND OF THE INVENTION 
   A problem in the delivery of fresh produce to retail markets is maintaining acceptable quality throughout the distribution system. In addition, shelf life must be maximized to benefit both the fresh produce processor and the consumer. It is also desirable to have a functional and aesthetic package that catches the consumer&#39;s eye and can be easily displayed on retail shelves without extra effort by in-store produce personnel. 
   Many package designs for fresh produce are based on maintaining a controlled or modified atmosphere inside the package during transport, storage, and display. Modified atmospheres help to maintain product quality and shelf life throughout product distribution, display, and use by consumers. For one segment of the produce market, a variety of fresh cut produce items are packed into a multi-compartment “Party Tray” consisting of a thermo-formed tray filled with fresh-cut produce with a lidding film hermetically heat-sealed to the flange of the tray. Because fresh produce continues to respire during storage, lidding film is made breathable either through perforations in the lidding film or the application of a breathable membrane over a hole in the lidding film. The required breathability of the entire package is determined by the type of produce inside the package, the respiration rate of that produce, and the expected storage temperature the package will endure. 
   One Party Tray currently in use consists of a clear polyester (PETE) dome which is heat-sealed with a PET lidding film, followed by snapping on an opaque cover. This Party Tray is displayed upside down so that the fresh produce can be viewed through the clear polyester dome. The opaque cover doubles as a serving tray for the consumer. There are several problems with this Party Tray design. First, the tray has the breathable member (micro-perforations or breathable membrane) on the lidding film which can be occluded by product or by the serving tray. Even though the lid or serving tray is designed with grooves to reduce the possibility of occluding the breathable member included on the lidding film, this is not a fool-proof method to assure that occlusion is avoided. Another deficit in the current “Party Tray” design is the fact that once the lidding film is removed from the thermo-formed dome, the tray cannot be hermetically resealed, thereby reducing the shelf life of the fresh produce contained within the tray. 
   An improved package for produce and similar fresh foodstuffs is desired. 
   SUMMARY OF THE INVENTION 
   The invention comprises an atmosphere controlled package which is particularly useful for storing fresh foodstuffs such as fruits and vegetables. The invention also comprises methods of forming and using the packaging. 
   In one embodiment, an atmosphere controlled, resealable foodstuff container includes a base tray and a cover. The cover and base tray are constructed of an essentially or substantially gas impermeable material. 
   The cover and base tray may be selectively connected and disconnected. When connected, the cover and base tray define a generally enclosed and sealed interior space. When disconnected, access to the interior space and foodstuffs or other stored goods, is provided. 
   In a preferred embodiment, the cover and base tray include mating locking/sealing members. A downwardly extending trough or tongue extends around the periphery of the cover for press-fitting into a recessed portion of the base against an upwardly extending wall thereof. 
   In one embodiment, the base tray is generally concave and the cover is convex, so that when connected they form a storage space. In one embodiment, the cover defines one or more compartments comprising raised areas which are separated at least partially from one another. The cover may be generally transparent to permit foodstuffs to be viewed therethrough, while the tray may be generally opaque for use as a serving platter. 
   The container includes at least one atmosphere control member for controlling the flow of gases through an opening in the container. In one embodiment, the atmosphere control member comprises a gas permeable membrane which is located over an opening in the container. In a preferred embodiment, the opening is located in a recessed portion on top of the cover, thus permitting the containers to be stacked upon one another without contacting the membrane and interfering with the operation thereof. 
   In one embodiment, a label extends over the atmosphere control member to obscure it from view. The label may extend over the entire recessed or inset area in which the atmosphere control member is located. Passages may be provided to permit gas to flow into and out of the area of the member. 
   The invention comprises a simple, and yet effective, container for fresh foodstuffs and other goods. Advantageously, the container can be resealed after it is first opened by a consumer. This aids in maintaining freshness of the stored foodstuffs over time. 
   Further objects, features, and advantages of the present invention over the prior art will become apparent from the detailed description of the drawings which follows, when considered with the attached figures. 

   
     DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a container in accordance with the invention; 
       FIG. 2  is an exploded view of the container illustrated in  FIG. 1 ; 
       FIG. 3  is an enlarged exploded view of a portion of the container illustrated in  FIG. 1 ; 
       FIG. 4  is an enlarged assembled view of the portion of the container illustrated in  FIG. 4 ; and 
       FIG. 5  is a cross-sectional view of the portion of the container illustrated in  FIG. 4  taken along line  5 - 5  therein. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In the following description, numerous specific details are set forth in order to provide a more thorough description of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without these specific details. In other instances, well-known features have not been described in detail so as not to obscure the invention. 
   In general, the invention comprises packaging which is particularly suited for storing and transporting fresh foodstuffs, such as fruits and vegetables. The packaging comprises a re-sealable, atmosphere-controlled container. Preferably, the container is comprised of at least two mating portions which are essentially gas impermeable, with at least one of the mating portions having an associated atmosphere control member. 
   One embodiment of the invention will be described with reference to  FIG. 1 .  FIG. 1  illustrates a foodstuff package or container  20 . As best illustrated in  FIG. 2 , in one embodiment, the container  20  comprise two selectively mateable portions  22 , 24 . As illustrated, a first portion  22  comprises a “top” or “cover” of the container  20 , while the second portion  24  comprises a “bottom” or “tray” of the container  20 . It will be appreciated that the terms “top” and “bottom” are relative, in that the container  20  may be placed in various orientations. These particular terms are utilized with reference to the particular orientation of the container  20  as illustrated. 
   In one embodiment, the container  20  is generally rectangular in peripheral shape. The container  20  may have a variety of shapes, however, such as oval, square, round, triangular or even irregular. Generally, the shape of the container  20  is dictated by the shapes of the top and bottom portions  22 , 24  thereof. 
   As indicated, the bottom portion  24  of the container  20  is preferably configured as a tray. The top portion  22  is configured as a cover having one or more compartments. In this configuration, foodstuffs are generally located in the compartments of the top portion  22  and retained or enclosed by the bottom portion  24 . In use, the container  20  is generally oriented so that the bottom portion or tray  24  rests upon a support surface, while the top portion or cover  22  is located over and encloses the foodstuffs. 
   Referring to  FIGS. 2 and 5 , the bottom portion or tray  24  has an inside or top surface  26 , an outside or bottom surface  28 , and a peripheral edge  30 . In one embodiment, the bottom portion  24  comprises a base having an outwardly extending (or upwardly extending, when the container is in its normal orientation) wall. As illustrated, the peripheral edge  30  comprises a flange which extends outwardly from the wall generally opposite the base. In this configuration, the bottom portion  24  is generally concave, in that the inside surface  26  has the form of a depression. The depth of the tray may vary depending upon the desired use. In one embodiment, the tray has a relatively shallow depth (for example, having a depth which is less than its peripheral dimension, such as dimension from side to side or end to end). 
   The top portion  22  may have a variety of configurations. Generally, the top portion  22  is configured as a container for containing foodstuffs. The top portion  22  has a periphery or outer edge  32 , an outside or top surface  34 , and an inside or bottom surface  36 . In one embodiment, the top portion  22  has a top with an outwardly extending (or downwardly extending, when the container is in its normal orientation) wall. As illustrated, the peripheral edge  32  extends outwardly beyond a “U” shaped trough  42 . This trough  42  is configured to tightly engage upstanding wall of the bottom portion  24 , thereby permitting the top and bottom portions  22 , 24  to engage one another in a press-fit locking arrangement, as described in more detail below. 
   Still referring to  FIGS. 2 and 5 , in this configuration, the top portion or cover  22  is generally convex, such that one or more portions of the outside surface  34  are raised or extend away from the edge  32 . In a preferred embodiment, the top portion  22  defines a plurality of compartments  38 . These compartments  38  are at least partially divided or separated from one another. As illustrated, certain portions of the top are raised or extend outwardly farther than others relative to the peripheral edge or flange  32 . The portions which extend outwardly define the compartments  38 , while the portions there between generally serve as dividers between the compartments. It will be appreciated that the number of compartments and their shapes and sizes may vary. As illustrated, there are three central compartments with two side compartments on either side thereof. There may be as few as one compartment (where the entire top of the top portion raised), but there are preferably at least two compartments and there may be, as illustrated, numerous compartments. 
   In a preferred embodiment, the top and bottom portions  22 , 24  are preferably constructed of a generally gas or air-impermeable material. Preferably, by “air-impermeable” it is meant that atmospheric gas at normal room pressures does not readily pass through the top and bottom portions  22 , 24 . For example, the top and bottom portions  22 , 24  may be vacuum formed from a plastic material. So that the food stuffs may be viewed by a consumer, the top portion  22  may be constructed of a generally clear or transparent material. In a preferred embodiment, the bottom portion  24  is constructed of a generally opaque material, such as a black plastic. In this manner, the bottom portion  24  may be used as a serving tray. 
   Means are provided for selectively connecting the top and bottom portions  22 , 24  to form a closed container. More preferably, the means allow the top and bottom portions  22 , 24  to be connected in a manner which causes the container  20  to define a generally sealed interior space (i.e. generally atmospherically sealed or controlled). Most preferably, the means for connecting allows the top and bottom portions  22 , 24  to be selectively connected and disconnected, meaning that the container  20  can be opened and closed, as desired. 
   In one embodiment, the top and bottom portions  22 , 24  are connectable by mating first and second locking or sealing members. As described above and illustrated in  FIGS. 2 and 5 , the bottom portion  24  includes an upwardly extending wall  40 . The wall  40  may have various shapes and sizes. In one embodiment, the wall  40  is located adjacent to the periphery  30  and slopes upwardly and outwardly to work with the trough  42  of the top portion  22  in a “wedging” arrangement to lock the top and bottom portions  22 , 24 . 
   As indicated above, the top portion  22  includes a mating trough or tongue  42 . The trough or tongue  42  is preferably defined at the bottom of the top portion  22 , near the periphery  32  thereof. The trough  42  and wall  40  are configured to mate, and as such, the trough  42  is located in a position on the top portion  22  which corresponds to the location of the wall  40  of the bottom portion  24 . 
   In a preferred embodiment, the trough  42  is sized and shaped to fit tightly against the wall  40 . When the wall  40  is continuous, the trough  42  is preferably continuous. As illustrated, an outside surface of the trough  42  is configured as a wall portion with the same slope and shape as the wall  40 . Preferably, that portion of the trough  42  is movable relative to the remaining portion of the top portion  22  (will flex inwardly towards the portion of the top separated therefrom by the trough), so that the wall portion will spring fit or compress into engagement with the wall  40 . In this manner, the top portion  22  may be press-fitted tightly into engagement with the bottom portion  24 . 
   The container  20  also includes means for controlling the atmosphere therein. When the top and bottom portions  22 , 24  are connected, they define a generally closed, sealed interior space. In other words, the atmosphere within the container  20  does not interact with the atmosphere outside of the container, owing to the generally atmosphere impermeable nature of the top and bottom portions  22 , 24  and their sealing connection. Preferably, however, the container  20  includes a means for controlling exchange of gases between the interior and exterior of the container  20 . 
   As illustrated in  FIGS. 2-5 , in one embodiment, the container  20  includes an atmosphere control member  44 . In one embodiment, the member  44  comprises a membrane which selectively allows gas to flow therethrough. 
   Referring to FIGS.  2 , 3  and  5 , the container  20  defines an opening  46 . In one embodiment, the opening  46  is located in the top portion  22 . The atmosphere control member  44  is associated with the opening  46 , preferably by being located over the opening, to selectively control the passage of gases through the opening  46 . 
   In one embodiment, the atmosphere control member  44  is a microporous film made from polyolefin polymers such as polypropylene or polyethylene. The member  44  is generally planar and is dimensionally larger than the opening  46 , whereby at least a portion of the member  44  extends beyond the opening around the periphery thereof. The member  44  may be sealed to the top portion  22 , such as with a pressure sensitive adhesive that is applied to the periphery of the atmosphere control member  44 . 
   The size and shape of the member  44  (and thus associated opening  46 ) may vary. The size of the member  44  and associated opening  46  may vary, at least in part, by the size of the container  20  (or the interior space), the types of foodstuffs to be stored, or other factors. The number of members  44  may also, or instead, be varied depending upon such factors. 
   For convenience, the member  44  may be located at the outside or top  34  of the top portion  22 . Preferably, the member  44  is inset from the very top of the top portion  22 , whereby if the containers  20  are stacked or if other items are placed on the container  20 , the member  44  is not blocked. In one embodiment, as illustrated, the member  44  is located at an inset portion  48  of the top of the top portion  22 . The inset portion  48  may comprise a slightly recessed area of one of the compartments  38 . One or more raised areas  50  at least partially surround the inset portion  48 . 
   The depth of the inset portion  48  relative to the raised areas  50  may vary. The depth need not be particularly great, but only sufficient to prevent a container or other object from resting directly on the member  44  and preventing or obstructing the flow of gases therethrough. Preferably, the inset portion  48  is relatively small, so that the raised areas  50  will support a portion of another container  50  or other object without that portion or object fitting within the inset portion  48  (i.e. the raised areas  50  generally prevent a portion of a container or other object from resting upon the member  44 ). 
   To allow gases to flow to and from the inset area  48 , one or more slots  52  or other passageways may be defined through or between the raised areas  50 . In this manner, if a container  20  or other object is resting upon the raised areas  50 , that container or object not only does not contact the member  44 , but does not occlude the inset area  48  from the atmosphere around the container  20 . 
   In a preferred embodiment, a packaging label  54 , such as containing consumer information, is located over the inset area  48 , and thus the member  44 , thus obscuring the member  44  from view, but not preventing its operation. In the embodiment illustrated in  FIG. 5 , the label  54  may be sized so that it is associated with the raised areas  50 , but covers or extends over the inset area  48 . In this manner, the member  44  is hidden from view, but gases are allowed to flow to and from the member  44  via the passageways  52 . 
   It will be appreciated that the container  20  may have a variety of other configurations which provide for one or more atmosphere control members  44 , but which ensure the proper operation thereof. 
   Use of the container  20  will now be described. As indicated, in a preferred embodiment, the top portion  22  defines one or more compartments  38 . As such, the top portion  22  is inverted (so that the inside surface  36  is facing upwardly) and loaded with foodstuffs. Different foodstuffs may be loaded into the various compartments, as desired. 
   Once filled, the bottom portion  24  is inverted and placed over the top portion  22  and the foodstuffs (i.e. the bottom portion  24  is oriented so that its inside surface  26  faces the top portion  22  and the foodstuffs). The top and bottom portions  22 , 24  are preferably connected to one another. In one embodiment, this comprises engaging the connecting or sealing means, such as by pressing the trough  42  of the top portion  22  into engagement with the wall  40  of the base portion  24 . 
   The container  20  may then be inverted so that it rests upon the bottom portion  24  and so that the foodstuffs are viewable through the top portion  22 . If not already applied, a packaging label  54  may be affixed to the container  20  over the atmosphere control member(s)  44 . 
   If desired, a seal may be associated with the container  20  to provide an indication to the consumer that the container  20  has not been opened prior to purchase. For example, a sealing member, such as a shrink or stretch band, may be located around the edge of the container  20  where the peripheral portions  30 , 32  of the top and bottom portions  22 , 24  are located adjacent one another (see  FIG. 5 ). Alternatively, a heat-sealable lidding film may be applied over the flange of the container  20 . 
   Once the top and bottom portions  22 , 24  are connected, the interior of the container is generally sealed. However, the atmosphere control member  44  selectively allows gas to exchange between the interior and exterior of the container  20 . In this manner, the atmosphere inside the container  20  is controlled. This ensures that the foodstuffs remain fresh. 
   Upon purchase by a consumer, the consumer may open the container  20 . The consumer may utilize the bottom portion  24  as a tray. Advantageously, a consumer may reseal the container  20 . In particular, the consumer may seal the top and bottom portions  22 , 24  back together, thus again sealing the interior space of the container and the foodstuffs therein. At that time, the atmosphere control member  44  again regulates the flow of gases between the exterior and interior of the container  20  to prolong the freshness of the foodstuffs during subsequent storage. 
   The container of the invention may have a variety of other configurations. In one embodiment, the bottom portion of the container may be relatively deep and the top may be shallow, so that the foodstuffs are filled into the bottom portion. In this configuration, the lid could be generally flat (except for preferably including an inset area or areas for the atmosphere control member(s)). 
   The top and bottom portions may connect one another in other fashions. For example, the top and bottom portions might engage one another in a tongue and groove configuration. 
   It is possible for the container to include more than one atmosphere control member and those members may be located on the cover or elsewhere (such as on the tray). 
   The container of the invention has numerous advantages. First, the container is simple in construction. The container can be sealed merely by connecting the top and bottom portions, and without the need for a sealing sheet. 
   The interior of the container is atmosphere controlled. Once closed, the interior is isolated from the exterior, except via the atmosphere control member(s). This promotes foodstuff freshness. 
   In addition, once opened, the container can again be closed and sealed. In this manner, the consumer can access the foodstuffs, store unused foodstuffs in the same container, and re-access the unused foodstuffs in the future. When the foodstuffs are re-stored, their freshness is extended because the foodstuffs are again located in an atmosphere controlled interior space. 
   Because the one or more atmosphere control members are located in an inset area, the containers may be stacked upon one another or other items may be placed on the container without interfering with the operation of the atmosphere control member. 
   The atmosphere control member is preferably associated with the container itself, so that it is positioned between the interior and exterior and is thus the sole control there between. This ensures that the flow of gases is not prohibited. 
   A packaging label may be located over the atmosphere control member(s) so that they are not visible, without interfering with their operation. 
   It will be understood that the above described arrangements of apparatus and the method there from are merely illustrative of applications of the principles of this invention and many other embodiments and modifications may be made without departing from the spirit and scope of the invention as defined in the claims.