Note: Descriptions are shown in the official language in which they were submitted.
CA 02506706 2008-05-21
FOOD PACKING TRAY WITH INTEGRAL JUICE ABSORBING BOTTOM
TECHNICAL FIELD
Containers for packaging, preservation, and display of juice-containing foods
at
retail sales locations.
BACKGROUND ART
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 United States patent 5,320,895 of Larsonneur et al, and United
States patent
6,278,371 of Hopkins. 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
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applied around the tray. In addition, the visual appearance of the blood-red
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 an aspect 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 another aspect of this invention to provide a food
package with juice absorbing capability and oxygen absorbing capability.
It is another object of yet another aspect of this invention to provide a food
package with juice absorbing capability and with a non-oxidizing atmosphere
therein.
DISCLOSURE 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:
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Figure lA 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;
Figure 1B is a sectional view of the closed cell foam tray of Figure lA, taken
along line 1B-
1 B of Figure 1A.
Figure 2A is a top view of a first embodiment of the juice-absorbing package
of the present
invention;
Figure 2B is a sectional view of the juice-absorbing package of Figure 2A,
taken along line
2B-2B of Figure 2A.
Figure 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;
Figure 3B is a sectional view of the juice-absorbing package of Figure 3A,
taken along line
3B-3B of Figure 3A.
Figure 4A is a sectional view of the tray of Figure 3B, and a preferred juice
absorbing pad,
prior to assembly thereof to form a preferred juice absorbing package;
Figure 4B is a detailed view of a portion of the juice absorbing pad and tray
bottom
depicted in the sectional view of Figure 6B, after the juice absorbing pad and
tray have been
assembled together
Figure 5A is a top view of a first embodiment of the foam tray and juice
absorbing pad of
Figure 4, prior to assembly;
Figure 5B is a top view of a second embodiment of the foam tray and juice
absorbing pad of
Figure 4, prior to assembly;
Figure 5C is a detailed view of a portion of the juice absorbing pad and tray
bottom
depicted in Figure 5B and in the sectional view of Figure 6B, after the juice
absorbing pad and tray
have been assembled together;
Figure 6A is a top view of an assembled preferred embodiment of applicants'
juice
absorbing package.
Figure 6B is a sectional view of the juice-absorbing package of Figure 6A,
taken along line
6B-6B of Figure 6A.
Figure 7A is a sectional view of an embodiment of a juice and oxygen absorbing
package
comprising an oxygen absorbing packet.
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Figure 7B is an enlarged detailed view of a portion of the juice and oxygen
absorbing
package of Figure 7A, depicting the oxygen absorbing packet therein.
Figure 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 Figure 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.
BEST MODE FOR CARRYING OUT THE INVENTION
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.
Figure 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. Figure 1B is a sectional view
of the closed cell foam
tray of Figure lA, taken along line 1B-1B of Figure 1A. Referring to Figures
lA 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.
Figure 2A is a top view of a first embodiment of the juice-absorbing package
of the present
invention. Figure 2B is a sectional view of the juice-absorbing package of
Figure 2A, taken along
line 2B-2B of Figure 2A. Referring to Figures 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.
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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"TM 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"TM 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 Figures 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.
Figures 3A - 6B depict aspects of a more preferred embodiment of applicants'
juice absorbing package, in unassembled and assembled states. Figure 3A is a
top view
of a preferred foam tray that is used as the main container of applicants'
preferred juice
absorbing package. Figure 3B is a sectional view of the juice-absorbing
package of
Figure 3A, taken along line 3B-3B of Figure 3A. Referring to Figures 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
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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 countersunlc
volume provides a
space within tray for the placement of a juice absorbing pad therein as
depicted in Figure 6B, the
details of which will be explained subsequently in this specification.
Figure 4A is a sectional view of the tray of Figure 3B, and a preferred juice
absorbing pad,
prior to assembly thereof to form a preferred juice absorbing package.
Referring to Figure 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. hl 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.
Figure 5A is a top view of a first embodiment of the foam tray and juice
absorbing pad of
Figure 4, prior to assembly. Referring to Figure 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. Figure 5A further depicts a plurality of adhesive dots 50
having been applied
immediately prior to assembly ofjuice 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 Figure 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 Figure 4A.
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Figure 5B is a top view of a second embodiment of the foam tray and juice
absorbing pad of
Figure 4, prior to assembly. The embodiment of Figure 5B is similar to the
embodiment described
and shown in Figure 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 Figure 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
applicants' juice absorbing package. Figure 5C is a detailed view of a portion
of the juice
absorbing pad and tray bottom depicted in Figure 5B and in the sectional view
of Figure 6B, which
depicts the phenomena providing such an advantage. Referring to Figure 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 Figures 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 Figures 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
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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 foain 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 surfactant-
containing polymer film
comprising such foam is between about 0 and about 70 degrees.
Referring to Figures 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
aboutØ050 inches,
and more preferably between aboutØ015 inches arid 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.
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Figure 6A is a top view of an assembled preferred embodiment of applicants'
juice
absorbing package. Figure 6B is a sectional view of the juice-absorbing
package of Figure 6A,
taken along line 6B-6B of Figure 6A. Referring to Figures 6A and 6B, juice
absorbing package 30
comprises juice absorbing pad 36 joined to closed cell foam tray 32, with non-
perforated 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 Figures 2A and 2B, because trench 44 is formed by
step 39 of tray 32 and
perimeter 41 of pad 36, 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 Figures 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 Figure 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 witli 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
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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 Figure 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 Figure 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 United States patent
6,458,877.
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
CA 02506706 2008-01-16
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 between about 20% and about 80% open cells. The
foam
of such tray is preferably 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
filtn
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 United
States patents 6,269,946, 6,269,945, 6,213,294, 6,112,890, 6,210,725,
6,023,915, 6,520,323
and 6,877,601.
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 gas-
permeable 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
United States
patents 6,877,601 and 6,520,323. 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 gas-
permeable solid resin tray, further comprises an oxygen absorber, disposed
within such
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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.,
United States patents 6,436,872, 6,248,690, 6,156,231 of McKedy. Such oxygen
absorbing packets are well known and are commercially available from suppliers
such as
e.g., Multisorb, Inc. of Buffalo, NY.
Figure 7A is a sectional view of one preferred embodiment of a juice and
oxygen
absorbing package comprising an oxygen absorbing packet. Figure 7B is an
enlarged
detailed view of a portion of the juice and oxygen absorbing tray of Figure
7A, depicting
the oxygen absorbing packet therein. Referring to Figures 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
United States
patent 6,455,620 of Cyr et al. Thus in the preferred embodiment of Figure 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 ineat 200.
Figure 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 fray of Figure 7A,
disposed
within a valved barrier bag. Referring to Figure 8, in one embodiment, the
oxygen and
juice absorbing package 90 is disposed through opening 74 in a heat shrinkable
barrier
bag 70 as described in applicant's United States patent 6,877,601. 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
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CA 02506706 2005-05-19
WO 2004/045962 PCT/US2003/036977
72, as described in applicant's aforementioned pending application and in
applicant's United States
patents 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 Figure 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., C02 Technologies
of West Des Moines
Iowa. In the embodiment depicted in Figure 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 patent 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.
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