Abstract:
A method and apparatus for packaging fruit in a container is disclosed. The method and apparatus increases the shelf life of fruit, even when unrefrigerated, so that a retailer can sell fruit as a point of purchase item without unacceptable loss due to overripening.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Application Ser. No. 61/296,194, filed Jan. 19, 2010 and entitled “Method and Apparatus for Packaging Produce,” the contents of which are hereby incorporated by reference in their entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a method and apparatus for packaging produce that improves marketability of the produce and improves overall shelf life. 
         [0004]    2. Discussion of the Related Art 
         [0005]    Fruits and vegetables are typically shipped and sold at retail in bulk and are not individually packaged. However, packaging individual fresh fruits or vegetables for a specific purpose, or packaging small numbers of such items, has been found to be a useful marketing tool. For example, while a purchaser might not buy even one fresh lime at bulk in the produce department of his or her local grocery store, he or she may readily buy three fresh limes, packaged together, at a convenience store or liquor store, where they may be sold specifically for use as garnishes for use in beer or cocktails. For example, it is well known to insert a wedge of lime in a bottle of Mexican beer or a lemon wedge in a Weiss (wheat) beer. 
         [0006]    In addition, convenience stores and the like are often ill-equipped to carry fresh citrus, since suitable storage—cooler than room temperature but not as cold as a beer fridge—is generally not available. As a result, stores that do not sell large amounts of fresh produce cannot order in volume and replenish produce the same way a large grocery store can, and are rarely able to stock fruit without an unacceptably high volume of loss due to decay. 
         [0007]    Other methods of extending the shelf life of fresh produce requires that exposure to oxygen be minimized or eliminated. These methods have included shrink wrapping, vacuum sealing, and modified environment packaging, all of which are expensive processes that work only to some degree. However, it is also known that elevated carbon dioxide levels slow citrus respiration rates, and provide another method for retarding ripening and decay. Thus, providing an atmosphere of elevated carbon dioxide with adequate oxygen exchange will increase the shelf life of citrus fruit without temperature control, i.e. even at room temperature, and without the expense of shrink-wrapping or other equipment or processes. 
         [0008]    Another advantage of the method and apparatus disclosed herein is an alteration of the carbon dioxide levels in the environment immediately surrounding the fruit, and a concomitant decrease in the rate of decay. Fruits packaged with use of the present invention therefore remain fresh and useable for a longer period of time than with previous packaging apparatus and methods. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    An embodiment of the invention is illustrated in the accompanying drawings, in which like reference numerals represent like parts throughout, and in which: 
           [0010]      FIG. 1  is a perspective view of an embodiment of the present invention, depicting a box shown from the front/right side; 
           [0011]      FIG. 2  is a perspective view of the box of  FIG. 1 , now shown from the rear/left side; 
           [0012]      FIG. 3  is a view of the top of the box of  FIG. 1 , shown with the top flap closed; 
           [0013]      FIG. 4  is a view of the top of the box in  FIG. 3 , now shown with the top flap open; 
           [0014]      FIG. 5  is a view of the bottom of the box in  FIG. 1 ; 
           [0015]      FIG. 6  is a drawing of the box of  FIG. 1 , showing an unconstructed plan of the box. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    The apparatus of the present invention may comprise a plastic box  10  sized to accommodate an arrangement of citrus fruits (not shown) in a linear configuration. The best currently known material having the freshness enhancing properties that are advantageous for this application is 12 gauge (.012) amorphous polyethylene terephthalate (APET). This particular material has the properties listed in Table 1, below, but it should be noted that other materials may well provide one or more of the advantageous properties of APET, and that other materials should be considered as within the scope of the invention. 
         [0000]    
       
         
               
               
               
             
           
               
                   
                 TABLE 1 
               
               
                   
                   
               
             
             
               
                   
                 Density (g/cm 3 ) 
                 1.33 
               
               
                   
                 Surface Hardness 
                 RM30 
               
               
                   
                 Tensile Strength (MPa) 
                 55 
               
               
                   
                 Flexural Modulus (GPa) 
                 2.3 
               
               
                   
                 Notched Izod (kJ/m) 
                 0.02 
               
               
                   
                 Linear Expansion (/° C. × 10 −5 ) 
                 8 
               
               
                   
                 Elongation at Break (%) 
                 300 
               
               
                   
                 Strain at Yield (%) 
                 3.5 
               
               
                   
                 Max. Operating Temp. (° C.) 
                 60 
               
               
                   
                 Water Absorption (%) 
                 0.16 
               
               
                   
                 Oxygen Index (%) 
                 20 
               
               
                   
                 Flammability UL94 
                 HB 
               
               
                   
                 Volume Resistivity (log ohm · cm) 
                 16 
               
               
                   
                 Dielectric Strength (MV/m) 
                 40 
               
               
                   
                 Dissipation Factor 1 kHz 
                 0.01 
               
               
                   
                 Dielectric Constant 1 kHz 
                 3.5 
               
               
                   
                 HDT @ 0.45 MPa (° C.) 
                 72 
               
               
                   
                 HDT @ 1.80 MPa (° C.) 
                 70 
               
               
                   
                 Material. Drying hrs @ (° C.) 
                 2 @130 
               
               
                   
                 Melting Temp. Range (° C.) 
                 260-280 
               
               
                   
                 Mould Shrinkage (%) 
                 0.4 
               
               
                   
                 Mould Temp. Range (° C.) 
                 20-30 
               
               
                   
                   
               
             
          
         
       
     
         [0017]    Referring now to the drawings,  FIG. 1  shows box  10  having a front  12 , right side  14 , back  16 , left side  18 , top  20 , and bottom  22 . A seam S is located between right side  14  and back  16 . In the embodiment shown, seam S comprises a flap S f  that extends from back  16  and is adhered to right side  14 . However, box  10  may be constructed in any number of ways, with seam S in any number of locations. Alternately, box  10  may be constructed with multiple seams or no seams, and any known method of connection may be utilized. 
         [0018]    Back  16  may extend above the top edge of front  12  to form a header  24  with a back portion  26  and a front portion  28 . Front portion  28  extends below the top edge of front  12  so that when top  20  is closed, front portion  28  of header  24  is retained in place without additional adhesive or other retention means. Optionally, as shown, a hole or holes H can be punched in header  24  to sell product on peg hooks or the like. 
         [0019]    In another embodiment shown in  FIG. 6 , in which the reference numerals shown in  FIGS. 1-5  are incremented by 100, header  124  extends further above the top edge of front  112 , and hole H is substantially round and sized to fit over the neck of a standard beer bottle so that box  110  can be displayed for sale in conjunction with the display of a related product. 
         [0020]    Returning to  FIGS. 3 and 4 , it can be seen that top  20  includes top panel  30 , tuck portion  32 , and may include right and left flaps  34 ,  36 . The junction between top panel  30  and tuck portion  32  may include left and right slits or cut-outs  38 ,  40 , which can aid the produce packager in quickly inserting tuck portion  32  when closing top  20  as well as easing the opening of top  20  by the end consumer. 
         [0021]      FIGS. 5 and 6  show bottom  22 , which may be configured in any variety of ways. However, in order to obtain a relatively strong support such that produce will not fall through bottom  22 , the best currently known embodiment includes providing a bottom  22  that includes a first flap  42  bearing a tab  44  and a second flap  46  bearing a tab  48 . Right and left flaps  50 ,  52  are also provided, and an adhesive dot  54  is applied to each of right and left flaps  50 ,  52 , such that first flap  42  is adhered to right flap  50  and second flap  46  is adhered to left flap  52 . After being adhered, first flap  42  and second flap  46  are folded together with tab  44  being tucked under flap  46  and tab  48  being tucked under flap  42 . 
         [0022]    Naturally, the dimensions of each of the portions of box  10  can be varied in order to accommodate a variety of types and quantities of fruits. In the embodiment shown, which is designed to hold four limes, box  10  is 2.25 inches deep, 2.75 inches wide, and about 9 inches tall when constructed, which is 102.375 square inches. (Advantageously for marketing purposes in liquor stores and the like, this translates into approximately the size of a bottle of beer.) However, the package can be as small as 2.25 inches deep, 2.5 inches wide, and 6 inches tall, which yields 68.25 square inches of material, or as large as 2.75 inches deep by 3.5 inches wide by 9 inches tall, or 131.75 square inches of material. In determining the appropriate size for a particular package, it should be understood that the number of square inches of material affects the atmosphere that can be achieved within the package, and that there must be sufficient surface area of material per piece of fruit. The range that has been shown to produce acceptable results using 12 gauge APET material is 22-26 square inches of material per piece of citrus fruit. 
         [0023]    In use, the packager chooses the appropriate sized box for the fruit to be packaged, constructs box  10 , fills box  10  with the fruit, and closes top  20 . The atmosphere inside box  10  changes within the first 48 hours after packaging, with the oxygen level decreasing approximately 2% and the carbon dioxide level increasing approximately 2%. The rate of atmospheric change and the overall percentage of change depends on the type of fruit within the package, the maturity of the fruit, and the ambient temperature of the fruit/package. When the ambient temperature is decreased, the respiration rate of the fruit also decreases, such that the production of carbon dioxide is slowed. For example, at 42° F., carbon dioxide increase is dramatically lower than at 72° F., at which the production of carbon dioxide increases rapidly. 
         [0024]    In the best mode currently known, the produce items are arranged side-by-side in a linear arrangement within the boxes. As can be seen from the example below, the increase in shelf life and decrease in loss of weight when using the method and package of the present invention have been significant. 
       Example 1 
     Limes 
       [0025]      
         [0000]    
       
         
               
             
               
               
               
             
               
               
               
             
               
             
               
               
               
             
               
             
               
               
               
             
           
               
                   
               
             
             
               
                 4 limes, loose (not packaged), room temperature 
               
             
          
           
               
                 days elapsed 
                 total weight in pounds 
                 condition of fruit 
               
               
                   
               
               
                 day 1 
                 .84 
                 all green 
               
               
                 day 6 
                 .78 
                 green to light green 
               
               
                 day 18 
                 .70 
                 all limes brown and dried up 
               
               
                   
               
             
          
           
               
                   
                 total weight in pounds 
                   
               
               
                 days elapsed 
                 (including weight of package) 
                 condition of fruit 
               
               
                   
               
             
          
           
               
                 4 limes, packaged according to disclosure, room temperature 
               
             
          
           
               
                 day 1 
                 .92 
                 all green 
               
               
                 day 6 
                 .91 
                 all green 
               
               
                 day 18 
                 .90 
                 all green 
               
               
                 day 33 
                 .86 
                 all green 
               
               
                 day 38 
                 .86 
                 one of four limes shows 
               
               
                   
                   
                 some yellowing, three 
               
               
                   
                   
                 green 
               
               
                 day 49 
                 .84 
                 one lime yellowed, one 
               
               
                   
                   
                 lime shows some 
               
               
                   
                   
                 yellowing, two green 
               
               
                 day 66 
                 .82 
                 no data 
               
               
                 day 83 
                 .80 
                 one of four limes is still 
               
               
                   
                   
                 green, two are yellowed, 
               
               
                   
                   
                 one is yellowed with a 
               
               
                   
                   
                 brown patch 
               
               
                 day 100 
                   
                 of two remaining limes, 
               
               
                   
                   
                 one is green with some 
               
               
                   
                   
                 yellowing and one is 
               
               
                   
                   
                 mottled with a brown 
               
               
                   
                   
                 patch 
               
             
          
           
               
                 4 limes, packaged according to disclosure, refrigerated 
               
             
          
           
               
                 day 1 
                 .94 
                 all green 
               
               
                 day 6 
                 .94 
                 all green 
               
               
                 day 18 
                 .92 
                 all green 
               
               
                 day 33 
                 .91 
                 all green 
               
               
                 day 38 
                 .89 
                 all green 
               
               
                 day 49 
                 .88 
                 one lime mottled with 
               
               
                   
                   
                 brown spots, three green 
               
               
                 day 66 
                 .85 
                 no data 
               
               
                 day 83 
                 .84 
                 one lime is still green, two 
               
               
                   
                   
                 are yellowing, and one 
               
               
                   
                   
                 has a large brown patch 
               
               
                   
               
             
          
         
       
     
         [0026]    After 18 days, unpackaged limes were brown, hard, and unattractive. These limes were unsaleable. However, using the apparatus and method of the present invention, all of the limes were green and fresh-looking up to 38 days, representing over a 50% increase in shelf life. Further, two of the packaged limes held at room temperature were green and saleable at 49 days, one was saleable at 82 days, and one lime was useable, though not especially attractive, even at 100 days. 
         [0027]    The data shows that unpackaged limes lost 7% of their total weight in 6 days and 16% by day 18, while packaged limes lost only 1% of their weight in 6 days and only 2% after 18 days. It took packaged limes over 38 days to lose the same 7% that unpackaged limes lost in 6 days, i.e. over 6 times as long. Further, packaged limes lost a total of only 9% of their original weight after 49 days. Even after 83 days, the packaged limes maintained a greater percentage of their original weight than the unpackaged limes did at day 18. 
         [0028]    While it is not anticipated that many of the relevant consumers (retailers such as convenience stores and the like) will provide a refrigeration case for produce packaged with the apparatus and method of the present invention, refrigeration increases shelf life even further. Packaged limes that were also refrigerated lost only 5% of their total weight in 38 days, and all remained green and fresh-looking. After 49 days, refrigerated packaged limes lost only 9% of their original weight, and were somewhat better looking as compared to the room temperature packaged limes. Three of the refrigerated limes were saleable a full 83 days (over two and a half months) after packaging. 
         [0029]    Noteably, the instant experiment was performed with limes acquired from a summer crop, which are typically more delicate and prone to decomposition than spring and winter cycle limes. It is believed that the method and apparatus of the present invention may produce even greater preservation times and rates with spring and winter cycle limes. 
       Example 2 
     Lemons 
       [0030]      
         [0000]    
       
         
               
             
               
               
               
             
               
             
               
               
               
             
           
               
                   
               
               
                 4 lemons, loose (not packaged), room temperature 
               
             
          
           
               
                 days elapsed 
                 total weight in pounds 
                 condition of fruit 
               
               
                   
               
               
                 day 1 
                 1.14 
                 all yellow 
               
               
                 day 14 
                 1.02 
                 no data 
               
               
                 day 17 
                 1.00 
                 no data 
               
               
                 day 28 
                   
                 poor—would have been 
               
               
                   
                   
                 thrown away in grocery 
               
               
                   
                   
                 store setting 
               
               
                 day 42 
                 .85 
                 all four lemons are dry-appearing 
               
               
                   
                   
                 and browned 
               
               
                   
               
             
          
           
               
                 4 lemons, packaged according to disclosure, room temperature 
               
             
          
           
               
                   
                 total weight in pounds 
                   
               
               
                 days elapsed 
                 (including weight of package) 
                 condition of fruit 
               
               
                   
               
               
                 day 1 
                 1.13 
                 all yellow 
               
               
                 day 14 
                 1.11 
                 no data 
               
               
                 day 17 
                 1.10 
                 no data 
               
               
                 day 42 
                 1.08 
                 no data 
               
               
                 day 58 
                 1.06 
                 three lemons are in good 
               
               
                   
                   
                 condition, one is 
               
               
                   
                   
                 beginning to appear dry 
               
               
                   
                   
                 and brown 
               
               
                   
               
             
          
         
       
     
         [0031]    As with the limes in the prior example, four lemons were left unpackaged at room temperature, and four were packaged using the method and apparatus of the present invention, also at room temperature. (No refrigerated experiment was conducted for lemons.) As can be seen from the data above, the unpackaged lemons lasted no more than 28 days before they were unsaleable, while three of the packaged lemons were in excellent condition and one was in tolerable condition even at 58 days. 
         [0032]    The unpackaged lemons lost 0.29 lbs. in 42 days, a total loss of 25% of their total weight. In that same 42 days, the packaged lemons lost only 0.05 lbs., less than 5% of their total weight, and only lost 0.07 lbs. (about 6%) after 58 days. 
         [0033]    Similar experiments were conducted with oranges, tangerines, clementines, and a mixture of lemons and limes with similar results. It is believed that the method and apparatus of the present invention will increase the shelf life of any citrus fruit. Further, although non-citrus fruits have not been tested, it is believed that the principles disclosed, particularly those relating to the respiration of fruit and the carbon dioxide levels in the atmosphere at which they are stored, are applicable to many non-citrus fruits, and that apples, tomatoes, and other fruits may achieve longer shelf life with use of the method and apparatus of the present invention. 
         [0034]    It should be appreciated that, while this disclosure refers to produce items arranged in a vertical box such that each item is in contact with the adjacent item, the arrangement of produce items could also be horizontal, or could include multiple linear rows of produce items forming a grid or cube. In fact, any geometric or non-random arrangement of produce items is currently understood to provide the advantages of marketability and/or increased shelf life, and as such, all such arrangements should be considered to be within the scope of the invention. Further, the box could be pyramidal, tubular, or any other configuration that would suitably contain a geometric arrangement of produce items.