Food package with integral juice absorbing bottom

Information

  • Patent Grant
  • 6695138
  • Patent Number
    6,695,138
  • Date Filed
    Wednesday, November 20, 2002
    22 years ago
  • Date Issued
    Tuesday, February 24, 2004
    20 years ago
Abstract
A juice absorbing food package comprising a tray having a bottom bounded by an upwardly extending lip around the perimeter of the bottom and a liquid-absorbing pad comprised of polymer foam joined to the bottom of said tray, wherein the polymer foam is open cell foam. The tray of the juice absorbing package is overwrapped with gas permeable film, and may be provided with an oxygen absorbing substance therein. Alternatively, the overwrapped tray may be placed in a sealed barrier bag that is subsequently purged with a non-oxidizing gas such as carbon dioxide.
Description




This invention relates in one embodiment to disposable and/or recyclable packaging trays for retail sale of food at supermarkets, grocery stores, delicatessens, and the like, and more particularly to the packaging of juice-containing meats and poultry products for sale in such establishments.




FIELD OF THE INVENTION




Containers for packaging, preservation, and display of juice-containing foods at retail sales locations.




BACKGROUND OF THE INVENTION




Sales of juice-containing foods, particularly meats, packaged in individual trays are common in supermarkets, grocery stores, and delicatessens. It is common to package such foods in polymer foam trays, since such foam trays are lightweight, structurally strong, inexpensive, and sanitary. Such containers also are shaped to be nested closely to each other, so that a large number of containers can be shipped in a small volume shipping box.




However, while such foam trays are effective at containing juices leaked from meat held therein, if maintained in a substantially level orientation, they are not suitable for absorbing leaked juices. Such foam trays are typically made from closed-cell polymer foam, which is not wet by water and water-based juices. In addition, there is no pathway for juices to enter the void volume of the cells of such polymer foam, as the cells are closed and impermeable to water.




Absorbent open cell polymer foams are known, but a food tray formed of such open cell foam is unsatisfactory, because juices will leak through the foam wall, discolor the inside of the tray and escape from the container, and also, such open cell foam is not as structurally strong as closed cell foam. Alternatively, the practice of placing an absorbent fabric pad between the foam tray and the meat is practiced, but such practice is also unsatisfactory. Examples of such absorbent pads comprising fabric and/or fibers are provided in U.S. Pat. No. 5,320,895 of Larsonneur et al, and U.S. Pat. No.6,278,371 of Hopkins, the disclosures of which are incorporated herein by reference. When customers examine and inspect the meat by holding and manipulating the tray, such meat may slide within the tray, and the proper orientation of the pad and the meat may be disrupted. Additionally these fabric pads release absorbed juices when subjected to physical pressure by the consumer and so do not provide for a consumer acceptable product.




There is also the practice of simply packaging meat in such closed cell trays with no absorptive pad, but such practice is also unsatisfactory. When customers examine and inspect the meat by holding and manipulating a non-absorbing tray, and orient the tray vertically, the juice contained therein may leak out at the junction of the edge of the tray and the stretch-wrap film applied around the tray. In addition, the visual appearance of the bloodred juices flowing within the tray during inspection may provide a negative impression on the consumer.




Like many consumer products, a decision to purchase a food is often made based on both visual appeal and practical considerations. Thus there is a need for a meat package, which has juice absorbing properties, and which is of sufficient structural strength to support meat held therein during handling, and during transportation of the meat to the display location, the checkout/purchase counter, and to the customer's home.




It is an object of this invention to provide a simple, inexpensive food package with high structural strength and with juice absorbing capability.




It is a further object of this invention to provide a food package with juice absorbing capability and oxygen absorbing capability.




It is another object of this invention to provide a food package with juice absorbing capability and with a non-oxidizing atmosphere therein.




SUMMARY OF THE INVENTION




In accordance with the present invention, there is provided a food package comprising a tray having a bottom bounded by an upwardly extending lip around the perimeter of said bottom and a liquid-absorbing pad comprised of polymer foam joined to said bottom of said tray, wherein said polymer foam is comprised of between about 20 to about 90 percent open cells, said polymer foam has an average cell diameter of between about 1 and about 10 mils, said polymer foam has a density of between about 1 and about 20 pounds per cubic foot, and said polymer foam has a contact angle when placed in contact with water of about 0 to about 70 degrees.




In accordance with the present invention, there is provided such a food package further comprising a film overwrapping around the tray, and an oxygen absorbing substance disposed within the tray.




In accordance with the present invention, there is provided such a food package further comprising the film overwrapping and the tray disposed within a barrier bag, wherein a non-oxidizing gas is also disposed within the barrier bag.











BRIEF DESCRIPTION OF THE DRAWINGS




The invention will be described by reference to the following drawings, in which like numerals refer to like elements, and in which:





FIG. 1A

is a top view of a unitary closed cell foam tray of the prior art, used in packaging, and retail sale of meats, seafood, and the like;





FIG. 1B

is a sectional view of the closed cell foam tray of

FIG. 1A

, taken along to line


1


B—


1


B of FIG.


1


A.





FIG. 2A

is a top view of a first embodiment of the juice-absorbing package of the present invention;





FIG. 2B

is a sectional view of the juice-absorbing package of

FIG. 2A

, taken along line


2


B—


2


B of FIG.


2


A.





FIG. 3A

is a top view of a closed cell foam tray that is used as one part of the juice absorbing package of the present invention;





FIG. 3B

is a sectional view of the juice-absorbing package of

FIG. 3A

, taken along line


3


B—


3


B of FIG.


3


A.





FIG. 4A

is a sectional view of the tray of

FIG. 3B

, and a preferred juice absorbing pad, prior to assembly thereof to form a preferred juice absorbing package;





FIG. 4B

is a detailed view of a portion of the juice absorbing pad and tray bottom depicted in the sectional view of

FIG. 6B

, after the juice absorbing pad and tray have been assembled together





FIG. 5A

is a top view of a first embodiment of the foam tray and juice absorbing pad of

FIG. 4

, prior to assembly;





FIG. 5B

is a top view of a second embodiment of the foam tray and juice absorbing pad of

FIG. 4

, prior to assembly;





FIG. 5C

is a detailed view of a portion of the juice absorbing pad and tray bottom depicted in FIG.


5


B and in the sectional view of

FIG. 6B

, after the juice absorbing pad and tray have been assembled together;





FIG. 6A

is a top view of an assembled preferred embodiment of applicants' juice absorbing package.





FIG. 6B

is a sectional view of the juice-absorbing package of

FIG. 6A

, taken along line


6


B—


6


B of FIG.


6


A.





FIG. 7A

is a sectional view of an embodiment of a juice and oxygen absorbing package comprising an oxygen absorbing packet.





FIG. 7B

is an enlarged detailed view of a portion of the juice and oxygen absorbing package of

FIG. 7A

, depicting the oxygen absorbing packet therein.





FIG. 8

is a sectional view of one preferred barrier packaging system for absorbing juice and absorbing and/or purging oxygen from the atmosphere therein, comprising the overwrapped juice and oxygen absorbing tray of

FIG. 7A

, disposed within a valved barrier bag.











The present invention will be described in connection with a preferred embodiment, however, it will be understood that there is no intent to limit the invention to the embodiment described. On the contrary, the intent is to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.




DESCRIPTION OF THE PREFERRED EMBODIMENTS




For a general understanding of the present invention, reference is made to the drawings. In the drawings, like reference numerals have been used throughout to designate identical elements.





FIG. 1A

is a top view of a unitary closed cell foam tray of the prior art, used in packaging, and retail sale of meats, seafood, and the like.

FIG. 1B

is a sectional view of the closed cell foam tray of

FIG. 1A

, taken along line


1


B—


1


B of FIG.


1


A. Referring to

FIGS. 1A and 1B

, foam tray


10


comprises a substantially flat bottom


12


, bounded by an upwardly extended lip


14


around the entire perimeter


16


thereof. In use, a food product (not shown) such as, e.g. a piece of meat, poultry, or fish is placed upon bottom


12


of tray


10


, tray


10


is typically fully wrapped with clear stretch wrap film (not shown), thereby enclosing the food therein. Juices leaked from such food are retained within tray


10


by lip


14


, as long as tray


10


is maintained in a substantially horizontal position.





FIG. 2A

is a top view of a first embodiment of the juice-absorbing package of the present invention.

FIG. 2B

is a sectional view of the juice-absorbing package of

FIG. 2A

, taken along line


2


B—


2


B of FIG.


2


A. Referring to

FIGS. 2A and 2B

, juice-absorbing package


20


comprises a substantially flat bottom


22


bounded by an upwardly extended lip


24


around the entire perimeter


26


thereof, and a juice absorbing pad


28


suitably joined to the bottom


22


of tray


20


. Juice absorbing pad


28


may joined to the bottom


22


of tray


20


by a suitable liquid adhesive (not shown) applied to bottom


22


, prior to engagement with pad


28


, or by application of adhesive (not shown) around the perimeter


30


of pad


28


, or by heat seal means, or by application of a double sided adhesive tape (not shown) to bottom


22


of tray


20


, or to the underside of pad


28


, prior to the engagement of pad


28


with bottom


22


of tray


20


.




In one preferred embodiment, juice-absorbing pad


28


is made of a wafer of hydrophilic open cell foam, such that it is wettable, and absorbs water. In one more preferred embodiment, such open cell foam wafer is made from a resin selected from the group consisting of polyethylene, polyvinyl chloride, polyacrylonitrile (such as the “BAREX” resin sold by the British Petrolem/Amoco company), poly(ethylene terephthalate), polystyrene, rubber-modified polystyrene, ethylene viny acetate(EVA),mixtures of polystyrene and EVA, ethylenepolystyrene, interpolymers (such as “INDEX” interpolymers sold by Dow Chemical Corporation of Midland Michigan), polypropylene, polyurethane, polyisocyanurate, epoxy, urea formadehyde, rubber latex, silicone, fluropolymer or copolymers thereof or blends thereof.




In one embodiment, depicted in

FIGS. 2A and 2B

, juice absorbing pad


28


comprises an upwardly disposed impermeable surface


29


having a plurality of perforations


42


disposed therethrough. When juices leak from a piece of food (not shown), that is placed within juice absorbing package


20


upon surface


29


, such juices flow through perforations


42


, and are absorbed by the porous open cell inner core


27


of pad


28


.




In a further embodiment, juice-absorbing pad


28


is joined to the bottom


22


of tray


20


by use of a solvent that will partially dissolve or soften both tray


20


and juice absorbing pad


28


. With the mating surfaces of tray


20


and juice absorbing pad


28


partially dissolved and in a liquid or plastic state, when such surfaces of tray


20


and juice absorbing pad


28


are engaged with each other, a strong bond there between is provided after the evaporation of the solvent occurs. In one example of such an embodiment, a tray of polystyrene closed cell foam was bonded to a wafer of water absorbing polystyrene open cell foam with 70% open cells by the use of a mixture of ortho-, meta-, and para-xylenes. Other suitable bonding solvents include acetone, and mixtures of xylenes and methyl alcohol, or similar solvents that at least partially dissolve polystyrene.





FIGS. 3A-6B

depict aspects of a more preferred embodiment of applicants' juice absorbing package, in unassembled and assembled states.

FIG. 3A

is a top view of a preferred foam tray that is used as the main container of applicants' preferred juice absorbing package.

FIG. 3B

is a sectional view of the juice-absorbing package of

FIG. 3A

, taken along line


3


B—


3


B of FIG.


3


A. Referring to

FIGS. 3A and 3B

, foam tray


32


comprises a substantially flat bottom


33


, bounded by an upwardly extended lip


34


around the entire perimeter


31


thereof. In one embodiment, foam tray


32


comprises an array of indented or protruding dimples


35


disposed on bottom


33






In the preferred embodiment, foam tray


32


further comprises a step


39


disposed around the perimeter of flat bottom


33


, such that a substantially rectangular recessed or countersunk volume is formed within foam tray


32


by step


39


and flat bottom


33


. This countersunk volume provides a space within tray for the placement of a juice absorbing pad therein as depicted in

FIG. 6B

, the details of which will be explained subsequently in this specification.





FIG. 4A

is a sectional view of the tray of

FIG. 3B

, and a preferred juice absorbing pad, prior to assembly thereof to form a preferred juice absorbing package. Referring to

FIG. 4A

, juice absorbing pad


36


comprises a porous open cell inner core


37


bounded by an intact smooth skin


38


on one side, and a perforated smooth skin


40


on the other side. In the preferred embodiment, juice absorbing pad


36


is joined to foam tray


32


with the perforated skin


40


positioned adjacent to bottom


33


of tray


32


. Juice absorbing pad


36


is preferably joined to foam tray


32


by a plurality of adhesive dots


50


.





FIG. 5A

is a top view of a first embodiment of the foam tray and juice absorbing pad of

FIG. 4

, prior to assembly. Referring to

FIG. 5A

, juice absorbing pad


36


is depicted with perforated side


40


facing upward, thereby showing an array of perforations


42


disposed through perforated side


40


.

FIG. 5A

further depicts a plurality of adhesive dots


50


having been applied immediately prior to assembly of juice absorbing pad


36


with tray


32


.




Adhesive dots


50


preferably comprise a liquid adhesive. In one embodiment, foam tray


32


comprised polystyrene closed cell foam, juice absorbing pad comprised open cell polystyrene foam having at least 70 percent open cells, and adhesive dots


50


comprised a low molecular weight polyethylene hot-melt adhesive applied with a hot-melt glue gun. Other adhesives, which suitably adhere to the juice absorbing pad


36


and foam tray


32


, and which are inexpensive, easy to apply, and meet FDA and USDA requirements may be suitable. In one embodiment, it is preferred that adhesive dots


50


are elastic, after such dots are fully cured.




In the embodiment shown in

FIG. 5A

, adhesive dots


50


are applied to the bottom


33


of tray


32


. It will be understood that alternatively, adhesive dots


50


may be applied to perforated side


40


of juice absorbing pad


32


. In either case, after application of a plurality of adhesive dots


50


, assembly of juice absorbing pad


36


to tray


32


is performed by turning perforated side


40


of juice absorbing pad


36


toward bottom


33


of tray


32


, and pressing juice absorbing pad


36


against bottom


33


of tray


32


, as indicated by arrow


49


of FIG.


4


A.





FIG. 5B

is a top view of a second embodiment of the foam tray and juice absorbing pad of

FIG. 4

, prior to assembly. The embodiment of

FIG. 5B

is similar to the embodiment described and shown in

FIG. 5A

, with the exception being that instead of dots of adhesive being used to join pad


36


to tray


32


, a continuous bead


51


of adhesive is disposed near the perimeter of bottom


33


of tray


32


, formed by step


39


. Thus when pad


36


is assembled to tray


32


with perforated side


40


toward bottom


33


of tray


32


, interstice


44


(see

FIG. 4B

) is entirely sealed beneath pad


36


, and the height of interstice


44


is defined by the thickness of cured bead


51


of adhesive. Such a continuous bead


51


of adhesive is preferably applied to bottom


33


of tray


32


within between about 0.25 inches and about 0.5 inches of step


39


of tray


32


.




The sealing of interstice


44


beneath pad


36


is advantageous in certain applications of to applicants' juice absorbing package.

FIG. 5C

is a detailed view of a portion of the juice absorbing pad and tray bottom depicted in FIG.


5


B and in the sectional view of

FIG. 6B

, which depicts the phenomena providing such an advantage. Referring to

FIG. 5C

, juices are prevented from wicking into interstice


44


beneath pad


36


around the perimeter thereof by bead


51


of adhesive, which is disposed beneath and slightly inside of perimeter


41


of pad


36


. However, in this embodiment, juices collected in trench


44


formed between perimeter


41


of pad


36


and step


39


of tray


32


(see

FIGS. 6A and 6B

) wick into pad


36


through the porous, unsealed perimeter


41


of pad


36


, as indicated by arrow


52


. Subsequently, juices wick further into pad


36


, and when the open cells of pad


36


approach saturation, juices flow out through perforations


42


, and into interstice


44


, as indicated by arrows


54


. Thus, in this embodiment, the provision of a sealing bead


51


of adhesive disposed substantially around the perimeter


41


of pad


36


results in interstice


44


functioning as a compartment that holds additional juices in addition to what pad


36


absorbs.




Through experimentation, applicants have determined ranges of package component properties, which provide acceptable juice absorbing packages and are thus to be considered within the scope of the present invention. Referring to

FIGS. 4A-6B

, juice absorbing pad


36


is preferably between about


20


mils and about


300


mils thick, depending upon the size and juice content of the food to be packaged, one mil being equal to one one-thousandth (0.001) of an inch. Juice absorbing pad


36


is preferably comprised of open cell foam comprising between about 20 percent and about 90 percent open cells, the open cells thereof containing air comprising about 21 percent oxygen, prior to performing any packaging step that dilutes, purges, or absorbs such oxygen. Such open cell foam preferably comprises open cells having an average diameter of between 1 and 10 mils.




Such open cell foam preferably has a density of between about 1 and about 20 pounds per cubic foot, and such open cell foam preferably has a contact angle of from about zero to about 70 degrees when placed in contact with water. In one preferred embodiment, such open cell foam preferably further comprises from about 0.5 percent to about 15 percent by weight of surfactant, which renders such foam hydrophilic, thereby enhancing juice absorption of such foam.




One measure of the extent to which such foam is made hydrophilic is the contact angle of water upon a cast film of the surfactant-containing polymer comprising such foam. Such contact angle is customarily defined as the angle between the surface of a liquid and the surface of a partially submerged object, or of a container holding the liquid, at the line of contact. In the preferred embodiment, the contact angle of water upon the surfactantcontaining polymer film comprising such foam is between about 0 and about 70 degrees. Referring to

FIGS. 5A-6B

, the distance between the edge


41


of juice absorbing pad


36


and the step


39


of tray


32


(i.e. the width of trench


44


) is between about 0.001 inches and about 0.250 inches, preferably between about 0.025 inches and about 0.125 inches, and more preferably between about 0.040 inches and about 0.080 inches. The interstice


44


between bottom


33


of tray


32


and underside


40


of pad


36


is determined by the cured thickness of adhesive dots


50


or adhesive bead


51


, in embodiments in which adhesive is used. In such embodiments interstice


44


is between about 0.001 and about 0.075 inches, preferably between about 0.010 inches and about 0.050 inches, and more preferably between about 0.015 inches and 0.020 inches. In embodiments in which no adhesive is used, e.g. where solvent is used to partially dissolve some area of bottom


33


and underside


40


of pad


36


, and then pressing underside


40


of pad


36


against bottom


33


, as previously described, interstice


40


is approximately 0.000 inches to about 0.020 inches, the upper limit being determined by the deviation of bottom


33


of tray


32


and/or underside


40


of pad


36


from absolute flatness when such parts are joined together.




In a further embodiment (not shown), pad


36


is made with a serrated edge at perimeter


41


, which provides more surface area around perimeter


41


. Such additional surface area increases the rate at which pad


36


absorbs juices released by the food contained in the juice absorbing package. Such a serrated edge may be provided by cutting pad


36


using a toothed knife, which preferably has between


10


and


100


teeth per inch of cutting edge thereof.





FIG. 6A

is a top view of an assembled preferred embodiment of applicants' juice absorbing package.

FIG. 6B

is a sectional view of the juice-absorbing package of

FIG. 6A

, taken along line


6


B—


6


B of FIG.


6


A. Referring to

FIGS. 6A and 6B

, juice absorbing package


30


comprises juice absorbing pad


36


joined to closed cell foam tray


32


, with nonperforated side


38


of juice absorbing pad


36


facing outward. In use, a food product (not shown) such as, e.g. a piece meat or fish is placed upon non-perforated side


38


of juice absorbing pad


36


, and juice absorbing package


30


is typically fully wrapped with clear stretch wrap film, thereby enclosing the food therein. When juices leak from such food, they flow into a small trench


44


formed between the perimeter


41


of juice absorbing pad


36


and the step


39


of bottom


33


of tray


32


. Thus the use of a tray


32


with a countersunk bottom


33


formed by step


39


is preferable over the use of the simple, flat bottomed tray


26


of

FIGS. 2A and 2B

, because trench


44


is formed by step


39


of tray


32


and perimeter


41


of pad


36


, to thereby directing leaked juices into the perimeter


41


of pad


36


, and/or into the interstice


44


beneath pad


36


.




In addition, in the embodiment depicted in

FIGS. 4B and 5A

, leaked juices flow into interstice


44


between juice absorbing pad


36


and bottom


33


, into perforations


42


, and into porous open cell core


37


of pad


36


, as indicated by split arrows


46


. In this embodiment, applicants' juice absorbing package


30


(see

FIG. 6

) has a high juice absorbing rate, as well as capacity. Without wishing to be bound by any particular theory, applicant believes that when juice absorbing pad


36


is joined to the bottom


33


of tray


32


by use of dots


50


of elastic adhesive, such elastic adhesive may stretch, enabling juice absorbing pad


36


to separate slightly from the bottom


33


of tray


32


, due to the effect of a buoyant force and possibly a capillary force. Accordingly, interstice


44


is increased under the influence of such force, and the rate at which juice is absorbed by pad


36


is enhanced. It will be apparent that the presence of perforations


42


in juice absorbing pad


36


is also important, in that such perforations enable the flow of juices into open cell core


37


, through an otherwise impermeable smooth skin on pad


36


.




In one embodiment of applicants' juice absorbing package comprising a foam tray, such tray is preferably a closed cell foam tray comprising at least about 50 weight percent polymer having at least about 90 percent closed cells with juice absorbing package further comprising a juice absorbing pad of open cell foam. In use, such a package would be used to package meat, being overwrapped or lidded with PVC film or other suitable stretch wrap. In one further embodiment, the foam material that is formed into such trays is coextruded with a thin surface film that is fusible with such wrap, thereby enabling such wrap to be heat sealed to the foam tray, sealing the meat therein.




In one embodiment, juice absorbing pad


36


was made of open cell polystyrene foam, 0.25-inch thick, 4.6 inches wide, and 10.6 inches long, perforated on one side as shown in

FIG. 5

, and having a dry weight of 11.0 grams. Tray


32


was formed of material as described above, with a countersunk bottom having a step


39


0.25 inches high, a width of 4.8 inches, and a length of 10.8 inches, thereby forming a trench


44


approximately 0.1 inches wide and 0.25 inches deep for the collection of juices therein.




In an experiment, approximately 120 grams of water (the major constituent of meat juices) was poured into the juice absorbing package of

FIG. 6

, made with the 11.0 gram juice absorbing pad. It was visually apparent that the majority of such water was wicked into and absorbed by the juice absorbing pad. After one minute, the surplus water was poured from the tray, and the tray plus absorbed water was weighed. The juice absorbing pad absorbed 60.3 grams of water in one minute, i.e. more than five times its weight, demonstrating sufficient juice absorbing capacity and absorption rate for effective use in a juice absorbing package.




Additionally or alternatively to the use of an open cell foam pad for juice absorption, in a further embodiment, one could use a single piece, pieces, or pellets of a super absorbent polymer, such as those described in U.S. Pat. No. 6,458,877, the disclosure of which is incorporated herein by reference.




The aforementioned embodiments of applicants' preferred juice absorbing package are superior to other prior art packages in additional ways. By having the meat, fish, or other food packaged therein resting on the non-perforated skin of the juice absorbing pad, such food is not excessively depleted of juice in the region of contact with the pad. This results in the food having more uniform cooking, texture, and taste properties when prepared and consumed. In addition, the manner in which the juice absorbing package wicks juices inwardly from along the perimeter of such pad, and hides such juices provides a more aesthetically pleasing package, which better promotes retail sale of the food therein. Additionally, by separating the juices from the meat product the possibility of bacterial contamination is reduced and product safety is enhanced.




In further embodiments, the applicants' juice absorbing package further comprises a bactericide. In one embodiment, such a bactericide is disposed throughout a portion or substantially all of the porous structure of the juice absorbing pad. In another embodiment, such a bactericide is disposed through a second pad or a piece fabric placed between the bottom of the tray and the juice absorbing pad.




The present invention is not limited to the use of a closed cell foam tray as the main container of the juice absorbing package. In one further embodiment of applicants' juice absorbing package comprising a foam tray, such tray comprises at least 50 weight percent polymer comprising g between about 20% and about 80% open cells. The foam of such tray is preferably y without surfactant so that such tray is rendered hydrophobic, and will be substantially repellent and non-absorbing of leaked juices. Alternatively, the foam of such tray comprises at least about 50 weight percent hydrophilic polymer surfactant mixture comprising between about 20% and about 80% open cells. The juice absorbing pad of this embodiment preferably comprises open cell foam. In use, such a package would also be used to package meat, and overwrapped or lidded with PVC film or other suitable stretch wrap as described previously.




In another embodiment, applicants' juice absorbing package comprises a tray formed of a gas permeable solid resin, such as polypropylene, polystyrene, low-density polyethylene, amorphous poly(ethylene terephthalate), high-density polyethylene, and suitable mixtures thereof.




In other embodiments, the juice absorbing package of the present invention may be incorporated into other packaging having means to absorb, dilute, displace or control the concentration of oxygen therein. Such packaging is disclosed in applicant's U.S. Pat. No. 6,269,946, 6,269,945, 6,213,294, 6,112,890, 6,210,725, 6,023,915, and U.S. patent applications U.S. Ser. No. 09/906,280 and U.S. Ser. No. 10/280,034 the disclosures of which are incorporated herein by reference.




Thus, the previously described embodiments of the juice absorbing package comprising a closed cell foam tray, or an open cell foam tray without surfactant, or a gaspermeable solid resin tray, may be overwrapped or lidded with highly gas permeable film and placed in heat shrinkable barrier valve bag containing means for flowing a non-oxidizing gas such as carbon dioxide therein, as described in applicant's co-pending patent applications U.S. Ser. No. 10/280,034 and U.S. Ser. No. 09/906,280. Such a package would be advantageous in that it would provide juice absorbing capability, and an extended shelf life by reducing the exposure of the food packaged therein to oxygen.




In another embodiment having such advantages, the juice absorbing package comprising a closed cell foam tray, or an open cell foam tray without surfactant, or a gaspermeable solid resin tray, further comprises an oxygen absorber, disposed within such package, overwrapped, and placed in heat shrinkable barrier bag. The oxygen absorber may be a separate item, such as a packet comprising an oxygen absorbing material, such as iron powder. Such oxygen absorbing materials and packets are described in e.g., U.S. Pat. Nos. 6,436,872- 6,248,690, 6,156,231 of McKedy, the disclosures of which are incorporated herein by reference. Such oxygen absorbing packets are well known and are commercially available from suppliers such as e.g., Multisorb, Inc. of Buffalo, NY.





FIG. 7A

is a sectional view of one preferred embodiment of a juice and oxygen absorbing package comprising an oxygen absorbing packet.

FIG. 7B

is an enlarged detailed view of a portion of the juice and oxygen absorbing tray of

FIG. 7A

, depicting the oxygen absorbing packet therein. Referring to

FIGS. 7A and 7B

, oxygen absorbing packet


56


is disposed in package


90


, which is overwrapped by film


60


. In the preferred embodiment, oxygen absorbing packet is disposed upon bottom


33


of tray


32


, beneath juice absorbing pad


36


, within a pocket


58


formed therein. Such a placement of oxygen absorbing packet provides for a more aesthetically pleasing appearance to the consumer.




In yet a further embodiment alternatively or additionally to an oxygen absorbing packet, the function of oxygen absorption is provided by an oxygen absorbing composition incorporated within or coated onto the tray, absorbent pad and/or film used as an overwrap or lid for the tray of the package. One suitable oxygen absorbing composition is comprised of an oxygen scavenging polymer as described in U.S. Pat. No. 6,455,620 of Cyr et al, the disclosure of which is incorporated herein by reference. Thus in the preferred embodiment of

FIG. 7A

, overwrap


60


, tray


32


, and/or pad


36


further comprise an oxygen scavenging polymer, which reduces the exposure of the meat


200


contained within package


90


to oxygen, thereby increasing the shelf life of meat


200


.





FIG. 8

is a sectional view of one preferred barrier packaging system for absorbing juice and absorbing and/or purging oxygen from the atmosphere therein, comprising the overwrapped juice and oxygen absorbing tray of

FIG. 7A

, disposed within a valved barrier bag. Referring to

FIG. 8

, in one embodiment, the oxygen and juice absorbing package


90


is disposed through opening


74


in a beat shrinkable barrier bag


70


as described in applicant's pending U.S. patent application U.S. Ser. No. 10/280,034. The opening


74


of such barrier bag


70


is sealed, such barrier bag is heat-shrunk, and the atmosphere within bag


70


is evacuated through one-way valve


72


, as described in applicant's aforementioned pending application and in applicant's U.S. Pat. Nos. 6,269,945, 6,269,946, 6,213,294, 6,112,890, and 6,210,725.




In another embodiment, alternatively or additionally to oxygen absorbing packet


56


, a source of non-oxidizing gas is disposed within barrier bag


70


. Referring again to

FIG. 8

, a piece


110


of solid carbon dioxide is disposed within barrier bag


70


, prior to the sealing of opening


74


. Subsequently, solid carbon dioxide piece


110


sublimes as indicated by arrows


112


, purging the air therein, and providing a non-oxidizing atmosphere. Accordingly, the exposure of meat


200


contained in package


100


to oxygen is substantially eliminated, thereby greatly extending the shelf life of such meat prior to purchase.




In another embodiment, alternatively or additionally to solid carbon dioxide piece


110


, a carbon dioxide producing sachet is disposed within barrier bag


70


. Such sachets are well known and are commercially available from suppliers such as e.g., CO2 Technologies of West Des Moines Iowa. In the embodiment depicted in

FIG. 8

, sachet


114


is disposed within barrier bag


70


, and when moisture diffuses into sachet


114


as indicated by arrow


116


, carbon dioxide is produced by a chemical reaction, an is released into barrier bag


70


, as indicated by arrow


118


.




In another embodiment, tray


32


is provided with additional volume, and an additional compartment therein, in which the piece of solid carbon dioxide is disposed prior to the wrapping of tray


32


with film


60


, and the sealing of package


90


in barrier bag


70


, as described in the aforementioned applicant's Pat. No. 6,269,946.




It is, therefore, apparent that there has been provided, in accordance with the present invention, a food packaging tray with an integral juice absorbing bottom. While this invention has been described in conjunction with preferred embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.



Claims
  • 1. A food package comprising a tray having a bottom bounded by an upwardly extending lip around the perimeter of said bottom and a liquid-absorbing pad comprised of polymer foam joined to said bottom of said tray, wherein(a) said polymer foam is comprised of between about 20 to about 90 percent open cells, (b) said polymer foam has an average cell diameter of between about 1 and about 10 mils, (c) said polymer foam has a density of between about 1 and about 20 pounds per cubic foot, and (d) said polymer foam has a contact angle when placed in contact with water of about 0 to about 70 degrees.
  • 2. The food package as recited in claim 1, wherein said polymer foam contains between about 0.5 and about 15 weight percent of surfactant.
  • 3. The food package as recited in claim 1, wherein said tray further comprises a step disposed around said perimeter of said bottom and wherein said step and said bottom form a countersunk volume within said tray.
  • 4. The food package as recited in claim 1, wherein said tray is comprised of at least 50 weight percent of polymer.
  • 5. The food package as recited in claim 4, wherein said closed cell foam comprises at least 90 percent of closed cells.
  • 6. The food package as recited in claim 4, wherein said tray further comprises a step disposed around said perimeter of said bottom and wherein said step and said bottom form a countersunk volume within said tray.
  • 7. The food package as recited in claim 1, wherein said pad has a thickness of between about 20 mils and about 300 mils.
  • 8. The food package as recited in claim 1, wherein said tray comprises at least 50 weight percent hydrophilic polymer surfactant mixture comprising between about 20% and about 80% open cells.
  • 9. The food package as recited in claim 1 wherein said tray comprises at least 50 weight percent hydrophobic polymer comprising between about 20% and about 80% open cells.
  • 10. The food package as recited in claim 9, wherein said tray further comprises a step disposed around said perimeter of said bottom, and a countersunk volume formed by said step and said bottom.
  • 11. The food package as recited in claim 1, wherein said tray is comprised of a gas permeable solid resin.
  • 12. The food package as recited in claim 11, wherein said tray further comprises a step disposed around said perimeter of said bottom and wherein said step and said bottom form a countersunk volume within said tray.
  • 13. The food package as recited in claim 3, wherein said liquid absorbing pad further comprises an impermeable surface and a plurality of perforations disposed through said impermeable surface.
  • 14. The food package as recited in claim 13, wherein said impermeable surface of said liquid absorbing pad is disposed adjacent to said bottom of said tray.
  • 15. The food package as recited in claim 14 wherein said liquid absorbing pad is joined to said bottom of said tray with adhesive.
  • 16. The food package as recited in claim 15, wherein said adhesive is elastic adhesive when said adhesive is in a cured state.
  • 17. The food package as recited in claim 15, wherein said adhesive is disposed between said juice absorbing pad and said bottom of said tray in a plurality of dots.
  • 18. The food package as recited in claim 15, wherein said adhesive is disposed between said juice absorbing pad and said bottom of said tray in a continuous bead.
  • 19. The food package as recited in claim 18, wherein said continuous bead of adhesive is to disposed on said bottom of said tray within between about 0.25 inches and about 0.5 inches of said step of said tray.
  • 20. The food package as recited in claim 3, wherein said liquid absorbing pad is disposed within said countersunk volume and wherein said liquid absorbing pad and said step form a trench between said step of said tray and the perimeter of said liquid absorbing pad of between about 0.025 inches and about 0.125 inches wide.
  • 21. The food package of claim 20, wherein said trench is between about 0.001 inches and about 0.250 inches wide.
  • 22. The food package as recited in claim 3, wherein said liquid absorbing pad is disposed within said countersunk volume and wherein said liquid absorbing pad and said bottom of said tray forming an interstice between said liquid absorbing pad and said bottom of said tray between about 0.00001 inches and about 0.075 inches.
  • 23. The food package as recited in claim 22, wherein said interstice is between 0.00001 and 0.020 inches.
  • 24. The food package as recited in claim 22, wherein said interstice is between 0.010 and 0.050 inches.
  • 25. The food package as recited in claim 1, wherein said juice absorbing pad further comprises a bactericide.
  • 26. The food package as recited in claim 1, further comprising a film overwrapping around said tray.
  • 27. The food package as recited in claim 26, further comprising an oxygen absorbing substance disposed within said tray.
  • 28. The food package as recited in claim 27 wherein said oxygen absorbing substance is disposed in an oxygen absorbing packet.
  • 29. The food package as recited in claim 27 wherein said oxygen absorbing packet is disposed between said juice absorbing pad and said bottom of said tray.
  • 30. The food package as recited in claim 26, wherein said tray and said film overwrapping are disposed within a barrier bag.
  • 31. The food package as recited in claim 30, wherein a non-oxidizing gas is disposed within said barrier bag.
  • 32. The food package as recited in claim 31, wherein said non-oxidizing gas is carbon dioxide.
  • 33. The food package as recited in claim 32 wherein said carbon dioxide further comprises solid carbon dioxide disposed within said barrier bag.
  • 34. The food package as recited in claim 31 wherein said non-oxidizing gas is produced by a sachet disposed within said barrier bag.
CROSS REFERENCE TO RELATED PATENT APPLICATION

This application is a continuation-in-part of copending application U.S. Ser. No. 10/280,034, filed Oct. 24, 2002 CIP application U.S. Ser. No. 09/906,280, filed Jul. 16, 2001 now U.S. Pat. No. 6,520,323.

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Continuation in Parts (2)
Number Date Country
Parent 10/280034 Oct 2002 US
Child 10/300256 US
Parent 09/906280 Jul 2001 US
Child 10/280034 US