Note: Descriptions are shown in the official language in which they were submitted.
The present invention relates to an improved receptacle
of the type used to contain and display various food products, and
which acts to substantially improve the appearance and shelf-life
of the product.
It is conventional practice to display meat, poultry,
and other food products in individual packages which comprise a
supporting tray with an absorbent pad of tissue-like paper wadding
in the bottom of the tray to absorb any juices or liquids exuded
from the food product. A transparent outer plastic wrapping is
also usually employed to cover and surround the package. A major
problem associated with such packages is the fact that the exuded
liquids support the rapid growth of bacteria, which migrate back to
the food product and result in spoilage and discoloration thereof.
As will be apparent, such spoilage and discoloration quickly
renders the food product unsuitable for sale.
In an effort to alleviate the above problem, and to
extend the shelf-life of such food products, it has been proposed
to employ an absorbent pad in the package which includes an
imperforate plastic film positioned above a layer of absorptive
wadding, and such that the plastic film acts to retard the reverse
migration of the liquids back to the food products. Also, it has
been proposed to position a non-absorptive barrier above the
absorbent material for this purpose, note the United States Patent
to Niblack et al No. 3,026,209. While the above package construc-
tions provide a spatial relationship between the exuded liquids in
the pad and the food product, they nevertheless permit the sub-
stantial migration of bacteria back to the food product and thus
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are not totally satisfactory.
It is accordingly an object of the present invention to
provide a receptacle for displaying food products which substantial-
ly alleviates the problem of foocl spoilage and discoloration result-
ing from bacterial growth within the exuded liquids, and thus
materially contributes to the shelf-life of the food product.
The invention provides a receptacle for containing and
displaying food products which tend to exude liquids, such as meat
and poultry, and characterized by the ability to separate and
maintain the exuded liquids from the food product to thereby
minimize contamination of the food product and improve the appearance
and shelf-life thereof, and comprising
a food product supporting member having a wall said
supporting member comprising a flexible plastic sheet material, and
an absorbent pad overlying and resting upon said wall,
said pad comprising a mat of liquid absorbent material, and
imperforate, liquid impermeable upper sheet overlying and covering
said mat, and a bottom sheet of substantially liquid impermeable
material underlying said mat so as to be disposed between said mat
and said supporting member wall, the peripheral edges of said upper
and bottom sheets being sealed together to enclose said mat of
absorbent material therebetween, and said bottom sheet including a
plurality of openings which are sized to permit passage of a liquid
from said supporting member wall into said mat while substantially
precluding reverse flow of the liquid and any associated bacteria
back to the food product, and such that the liquid passes around
the edges of the pad and into said mat and is confined by said pad
out of contact with the food product.
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The disclosed display receptacle is aesthetically pleas-
ing, is able to hold and retain a substantial quantity of liquid,
and permits the use of chemical additives in the absorptive mater~
ial while preventing the additives from contacting the food product.
The liquids exuded from the food product thus pass around the
edges of the pad and onto the bottom wall of the supporting member,
and are drawn upwardly into the mat through the openings by
capillary action. Once in the mat, the liquids are confined
against reverse flow by the capillary action, and the imperforate
upper sheet acts to prevent migration of bacteria, which may
develop in the liquids, back to the food product. The supporting
member may be a flexible transparent plastic bag/ with the
- apertured bottom sheet of the pad disposed against the wall of the
bag, so that a food product may be retained in the bag in contact
with the upper sheet of the pad and the exuded liquids collected
and confined in the pad in the above-described manner.
The liquid absorbent material of the pad is preferably
composed of superposed layers of paper wadding and wood fluff, and
with the layer of paper wadding being disposed immediately adjacent
the apertured bottom sheet and so as to prevent dust from the wood
fluff from passing outwardly through the openings.
Some of the objects having been stated, other objects will
appear as the description proceeds, when taken in connection with
the accompanying drawings~ in which --
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Figure 1 is an exploded perspective view of
a receptacle for food products which embodies the features
of the present invention;
Figure 2 is a perspective view o~ the absorbent
pad of the present invèntion;
. Figure 3 is an enlarged, fragmentary perspective
view o~ the bottom sheet of the pad;
Figure 4 is an enlarged, fragmentary sectional
elevat;on.Yiew of the pad and taken,substantially alon~
the line 4-4 of Figure 2; ; i~
~igure S is an enlar~ed,~fr~gmentary sectional
elevation view showing the openings in the bottom sheet
and taken substantially along the:line~-5 of Figure 3;
Figure 6 is a perspectiv-er~iew of the display
receptacle as shown in Figure 1, toge~her with the packaged
food product and surrounding plasti~.i.wrap;
Figure 7 is a sectional v`i~ taken substantially
along the line 7-7 of Figure 6;
Figure 8 is a perspectivë-view of another embodi-
ment of the receptacle, which comprisés a pad disposed
. within a flexible transparent plastic bag, and further
illustrating the packaged food product and
Figure 9 is a sectional view taken substantially
. àlon~ the line 9-9 of Figure 8. .
Referring more specifically to the drawings,
- Figure 1 discloses a display receptacle which embodi~s
~ the present invention, and`which comprises a support tray
: 10, and an absorbent pad 12. The support tray 10 may
` conveniently be fabrica~ed from a relatively rigid molded
foam plastic material, and includes a generally rectangular
~ bottom wall 14 and an upstanding peripheral side wall
; - 15. The absorbent pad 12 is also rectangular, and is
` sized-to overlie substantially the full area of the bottom
wall 14 sf th~ tray. In use, the pad 12 is positioned
upon the bo~tom wall 14, and the food product B .(note
Figure 6) is positioned to rest upon the pad. Further,
an ou~er wrapping of suitable thermoplastic film material
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17 may be positioned over the ood product and heat sealed
beneath the tray 10 in the conventional manner, to form
the completed food package.
The pad 12 comprises a mat 16 o liquid absorbent
material, an upper sheet 18 of substantially liquid imper-
meable hydrophobic material overlying and covering the
mat of absorbent ma~erial, and a bottom sheet 19 of hydro-
phobic material underlying the mat of absorbent material
- so as to be disposed between the mat and the tray bottom
wall 14.
The thickness of the mat 16 may be varied to
control the absorbency thereof, and typically is between
about 1/8 to 1~4 inches so as to permit absorption and
retention of a substantial quantity of liquid~ The mat
may be composed of a number of absorbent materials, such
as stacked layers of tissue-like wadding, a mat of con-
ventional defiberized wood pulp (known in the art as wood
fluff), a mat of synthetic pulp such as rayon, a mat of
cotton, or combinations of ~he above.
In the preferred embodiment as illustrated herein,
the mat 16 is composed of hydrophilic cellulose base~fibers,
and more particularly, the mat is composed of a relatively
thick layer of wood fluff 20, and a relatively thin layer
of tissue-like paper wadding 21. Wood fluff is well known
in the art and consists of defiberized cellùlose fibers
which have been formed into a compressed batt in the manner
of a non woven fabric. Thè flu~f layer has little or
no consistency or integrity, and it is thus difficult
to maintain in web form during manufacturing operations.
The paper wadding 21, which is also known in the art,
is produced on a ~ourdrinier paper making machinè, ànd
may, if desired, be creped for added body. The wadding
typically has a texture similar to household facial tissue,
and has substantially more integrity than does the wood
; 35 ~luff.
~ he layers of wadding and wood fluff are superposed
and mechanically interconnected by the diamond-shaped
emb~ssing 22 to maintain the relative positioning thereof
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and the integrity of the wood fluf, and to ~acilitate
handlinq of the flu~f during the manufacturing operations.
The embossing 22 typically comprises myriad distinct
~ indentations along the lines of the diamon shaped pattern
! 5 and which serve to compact and thereby interconnect the
superposed layers along those lines. Such embossing may
be imparted to the mat by passing the superposed layers
through conventional emhossing rolls (not shown). As
best seen in Figure 4, the wadding layer 21 is preferably
disposed immediately adjacent the perforated bottom sheet
19 as hereinafter further described, and in this orientation,
it has been found that the wadding layer also acts to
prevent any loose fluff dust from passing through the
openings and possibly contaminating the food product.
Various additives may be added to the mat to
increase its liquid absorbency. A particular example
of a suitable additive of this type is a synthesized starch,
such as the starch-acrylonitrile graft co polymer as des-
~ribed in U.S. Patent No. 3,661,815. This product is
marketed commercially as a free flowing powder, which
may be either sifted onto the fluff layer or sifted into
the 1uff chamber when the layer is being formed. In
addition, a bactericidal agent, such as potassium sorbate,
- may be added to the mat to retard bacterial growth.
The upper and lower sheets 18 and 19 are typically
of like composition and are composed of a material which
is non-reactive to food products. For example, the sheets
may comprise a flexible thermoplastic film, such as poly-
ethylene having a thickness between about 00035 to ~005
inches. The peripheral edges of the upper and bottom
sheets are preferably sealably secured together as shown
at 23 by any suitable means, such as a hot melt adhesive
seal, or by heat sealing, to thereby sealably enclose
the mat of absorbent material therebetween. In addition,
the bottom sheet 19 includes a plurality of minute openings
24 which permit the passage of a li~uid from ~he tray
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bottom wall into the absorbent material. The openings
24 are distributed substantially uniformly over the full
area of the sheet and typically have a density of between
about 15 and 100 per square inch, and preferably between
about 80 to 90 per square inch. In this regard, the open-
ings 24 may be formed by a perforating operation, such
as by contacting the film with a roll covered with pins
having a diameter of about .01 inches, an~ of the type
used on a textile carding cloth. Such perforating operation
1~ results in the openings having a diameter of about .01
inches, and peripheral portions 25 (note Figure 5) which
extend outwardly from the sheet. Also, the sheet is oriented
so that the peripheral portions 25 extend toward the mat
16 and thereby act to further retard the passage of liquid
outwardly from the mat and through the sheet.
In use, the juices or liquids from the food
product resting on the pad 12 will tend to flow downwardly
onto the botto~ wall 14 of the tray and beneath the pad.
The capillary action of the absorbent material in the
mat 16 tends to lift these liquids into the pad where
they are held out of contact with the food product.
The upper sheet 18 prevents these absorbed liguids and
any additives in the mat ~rom directly contac~ing the
food product, and the combination of the capillary action
?5 and the small size and construction o~ the openings 24
acts to retard the reverse flow of the liguids through
the openings. Thus substantially all migration of the
exuded liquids back to the food product is precluded,
thereby significantly alleviating the problems of spoilage
and discoloration. Further, the upper surface of the
sheet 18 remains relatively clean and smooth in use thereby
resulting in an aesthetically pleasing appearance.
Figures 8 and 9 illustrates a further embodiment
of the present invention wherein the pad 12 as described
above is disposed within a transparent flexible plastic
bag 26 having a closeable end opening. The pad is dis-
posed with the aper~ured bottom sheet 19 contacting the
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wall of the bag, and the food product B is preferably
oriented so as to overlie the pad and rest upon the upper
sheet 18. Thus the exuded liquids will flow downwardly
and beneath the pad in the manner described above, where
they are drawn into the mat and thus confined ~ut of
contact with the food product.
It has also been found that the pad 12 has
separate utility as a hydrating or moisturizing device,
whereby moisture may be provided to various food products,
such as lettuce or mushrooms, while stored in a closed
container or package. In particular, the pad may be
thoroughly saturated by dipping in water, and then placed
in the food container or package~ The water in the pad
will slowly varporize, and pass outwardly through the
openings 24 to thereby maintain a relatively high humidity
leYel within the container or package.
In the drawings and specification, there has
~ been set forth a preferred embodiment of the invention,
and although specific terms are employed, they are used
in a generic and descriptive sense only and not for pur-
poses of limitation.
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