NZ222810A - Package containing oxygen-sensitive food and oxygen scavenger - Google Patents

Description

New Zealand Paient Spedficaiion for Paient Number £22810 222810 .2 8 Ai-k 123Q UOVPMJlfiCM: NEW ZEALAND PATENTS ACT, 1953 No.: Date: COMPLETE SPECIFICATION PACKAGING OF OXYGEN SENSITIVE FOOD PRODUCTS SUBSTITUTION OF APPLICANT UNDER SECTICfJ 24 VJ.&. &CACjCL,H-CO.- £<: Oor\r>t M/ We, Wi~Rr GRACE' SrCO., a corporation organized and existing under the laws of the State of Connecticut, U.S.A., of 1114 Avenue of the Americas, New York, New York 10036, U.S.A., hereby declare the invention for which we pray that a patent may be granted to $iQ(/us, and the method by which it is to be performed, to be particularly described in and by the following statement: - (followed by page la) $ A* ;T E N j>- ;:/1 ;7 ;v ;-4DEC1987 ;/> ;• v:; ;PACKAGING OF OXYGEN SENSITIVE FOOD PRODUCTS ;BACKGROUND OF THE INVENTION ;The present invention relates to the packaging of food products, and more particularly to the packaging of oxygen sensitive food products such as liquids contained in glass bottles or other vessels. ;Liquids such as grape wines are customarily packaged in glass bottles. Glass offers the advantage of an extended shelf life, with low permeability to oxygen and other gases. In bottling oxygen sensitive liquids such as grape wines, oxidation can cause a deterioration in quality. This deterioration can be measured by the drop in sulfur dioxide content, initially between 31 and 34 parts per million. After significant oxidation of the wine, the sulfur dioxide content may drop to 24 to 27 parts per million, or even significantly lower in some cases depending on the type of wine bottled and closure on the bottle. Thus, the vessel and closure used for packaging the wine is critical to its shelf life and maintenance of quality. ;The general popularity of wine has demonstrated itself in the use of and sale of wine in the airline industry. One critical problem encountered in the use of glass bottled wine is the weight penalty associated with a relatively heavy material being carried on airline flights. It is well known that the airline industry could attain considerable cost savings by using lighter weight materials for packaging wines and other beverages sold in flight. Various lighter weight plastic vessels including PET (polyethylene terephthalate), and multilayer plastic materials are available for this purpose. ;404/861112/4/1 ;\Ck ;22 2 8 1 ® ;These lighter weight materials, while providing a cost savings in terms of weight, suffer in many cases from a lesser ability to prevent oxidation of the bottled beverage both in closure integrity and permeation of oxygen through the vessel. ;It is therefore desirable to make use of lower weight and relatively inexpensive plastic bottles for use in packaging oxygen sensitive liquids such as grape wine, while maintaining the extended shelf life associated with glass vessels. ;Of interest is U. S. Patent No. 2,925,346 issued to Harper et al and disclosing the packaging of cured meats by placing the product in a transparent pliable, flexible container, vacuumizing the interior of the package, and backfilling with a source of oxygen-free nitrogen or nitric oxide. A gas impermeable flexible film is used as the packaging envelope. ;Of interest is U. S. Patent No. 2,955,940 issued to B. E. Williams and disclosing the treatment of vegetable produce by evacuation of air from the produce followed by gas treatment with carbon monoxide and nitrogen.' ;• ;Of interest is U. S. Patent No. 4,536,409 issued to Farrell 'and disclosing an activatable oxygen scavenger used as a part of a packaging structure for comestibles, the oxygen scavenger activated by water vapor. The oxygen scavenger is compounded into interleaving adhesive layers, and is preferably potassium sulfite. ;It is an object of the present invention to provide a package, and a method for packaging oxygen sensitive food products e.g. liquids such as grape wines in relatively light weight containers without substantially diminishing the shelf life of the oxygen sensitive food product. ;It is another object of the present invention to provide a package and method for packaging oxygen sensitive food products such as liquids wherein the quality and taste of the food product are not substantially impaired. ;404/S64-14-2-/4/-2 ;- > ;il L ;: 2 ;SUMMARY OF THE INVENTION ;In one aspect of the invention, a method for extending the shelf life of oxygen sensitive contained food products comprises inserting the contained product into a pouch comprising a polymeric material and having an oxygen barrier layer; placing an oxygen scavenger in the pouch; vacuumizing the pouch; gas flushing the pouch with an inert gas; and heat sealing the pouch. ;In another aspect of the present invention, a package for extending the shelf life of oxygen sensitive contained food products comprises a heat sealed pouch comprising a polymeric material and having an oxygen barrier layer; and a vacuumized, gas flushed interior of the pouch containing the contained food product and an oxygen scavenger. ;DEFINITIONS ;The term "contained" as used herein refers to an integral enclosure which holds a food product, especially a liquid, and although directed primarily to glass and plastic bottles, can also include cans and other rigid containers, paperboard boxes, flexible pouches, bag-in-box, and the like. ;The term "oxygen sensitive food products" refers herein primarily to liquids such as grape wines, and also to both alcoholic and non-alcoholic beverages, fruit juices, nectars, and other products which are adversely affected in quality, taste, or shelf-life by the presence of oxygen, or which can benefit from packaging systems which reduce the exposure of the product to oxygen. ;DESCRIPTION OF THE PREFERRED EMBODIMENT ;A grape wine is bottled in a 187 ML PET (polyethylene terephthalate) bottle and placed in a high oxygen barrier film. This film has an oxygen transmission of less than lcc/m /24 hours at STP. The bottled ;5 liquid may be assembled in a corrugated grid or other retainer in groups of, ;for example 24 bottles per case or any other desirable number of bottles depending on the marketing and shipping needs of the customers. Films ;2 ;having higher oxygen transmissions of between about 10 to 15cc/m /24 hours at STP, showed some slight improvement in shelf-life of contained food 10 product when packaged in accordance with this invention. A preferred film has an oxygen transmission of less than 5, and more preferably less than ;2 ;lcc/m /24 hours at STP. A preferred pouch comprises a multilayer film including a layer of ethylene ~vinyl alcohol copolymer. ;An oxygen absorber or scavenger is added to the pouch formed from the barrier film. These scavengers are available commercially from several 15 suppliers and typically contain one of various oxygen—absorbing agents in a packet or small bag. One such example is the P500 Tamotsu free oxygen absorber. ;The barrier pouch, now containing the bottled liquid and an oxygen scavenger, is vacuumized on a machine capable of achieving a high vacuum, 20 and then back flushed with an inert gas. Such gases include 100% CC^, ;or combinations of CO^ and N^. A final heat seal closure is applied to the pouch to hermetically seal the pouch. ;This package permits the removal of remaining oxygen within the package, by means of the oxygen scavenger usually within about 24 hours, 25 leaving a very small residual amount, typically less than 0.01%, of oxygen within the pouch. At the same time, the high barrier film pouch prevents additional oxygen from entering the package in any significant amount. ;In this way, packaging and shipping costs are reduced by using a • lighter weight plastic bottle instead of the heavier glass bottle, but 30 without detrimental effect on the shelf life and quality of the liquid. ;c>'% ;404/8 61irt2-/4-/4- its: __ -*\\ /■ ? G /-'Crt rn-," Ar V.. 0 >990, m!f 2 2 8 1 0 After the final heat seal closure, the pouch is placed in a standard shipping corrugated box or the like. This packaging method allows the shipper to reduce the cube per box unit by 36% in a 48 bottle case.

Thus, more product can be shipped per pallet, providing a volume reduction over past methods.

A suitable apparatus for gas flushing the pouch during the gas flushing step is a Koch-Multivac AG800 vacuum chamber machine.

It has been found that this method permits a reduction in the weight of a case of bottled wine of about 12.5 pounds, or about a 33% reduced weight savings. A savings of between $10.00 and $25.00 per pound of reduced weight transported per year are possible in the airline industry, where weight savings can play an important role in cost savings.

The invention may be further understood by reference to the comparative examples below.

EXAMPLE 1 In a four month test conducted by an outside laboratory, Chardonnay wine was packaged in different ways to determine the improvements, if any, obtained by the practice of the present invention.

Wine was bottled in glass bottles, Gamma (TM) bottles, and polyethylene £erephthalate bottles.

Twenty four of each type of bottle, filled with the Chardonnay wine, were placed in a corrugated tray and held at room temperature for four months.

Additional bottles were prepared as described above, and the trayed bottles were placed in a P203B Cryovac (TM) high oxygen barrier pouch. This pouch had dimensions of about 14 inches in width and about 23 inches in length. A high vacuum was pulled on the pouch, which was then back flushed with 100% carbon dioxide gas. The pouch was thereafter closed by heat sealing. 0k 22 2 8 s Still additional samples were prepared, using the barrier pouch, vacuumization and back flushing steps, but with the additional step of inserting an oxygen scavenger, P500 Tamotsu FOA (free oxygen absorber) inside the pouch prior to vacuumization.

In each of the three methods, Che wine was allowed to stand for about four months at room temperature. Analysis was made by a blind taste panel test.

It was found that the overall quality of the wines was improved by the use of the high barrier pouch combined with vacuumization and back 10 flushing with 100% carbon dioxide, and even further improved by the additional use of an oxygen scavenger inserted into the pouch prior to vacuumization.

The results of these tests were further supported by tracking the level of sulphur dioxide content in each tested wine. The sulphur dioxide 15 content of wine packaged in accordance with the invention showed the least deterioration in SO^ level.

EXAMPLE 2 Wine was bottled in 187 milliliter glass, trilayer laminate, and PET bottles. Some of these samples were further packaged in accordance with 20 the present invention, i.e. as described in Example 1, using barrier pouch, an oxygen scavenger, high vacuumization and back flushing with 100% carbon dioxide.

All samples had an initial sulphur dioxide content of about 31 parts per million.

It was found that, after 112 days of storage at room temperature, the samples packaged in accordance with the invention as described above, had approximately the same drop in sulphur dioxide content as the wine bottled in glass bottles without further processing. (o figs* 7 V P Additional data indicated that this relationship remained substantially unchanged up to about 131 days.

Although the preferred embodiment and examples have been directed principally to the packaging of grape wine, one skilled in the art will understand that this invention can be very suitable for use with other oxygen sensitive liquids such as fruit juices.

It will be clear to one skilled in the art, after review of this disclosure, to make obvious modifications and changes in the method for packaging and in the package itself. Therefore these modifications are deemed to be within the scope of the invention, as defined in the claims following.

AQA+S&O-4-2/4/7

Claims (11)

WHAT WE CLAIM IS:

1. A method for extending the shelf life of oxygen sensitive contained food products comprising: - a) inserting the contained product into a pouch comprising a polymeric material and having an oxygen barrier layer; b) placing an oxygen scavenger in the pouch; c) vacuumizing the pouch; d) gas flushing the pouch with an inert gas; and e) heat sealing the pouch.

2- A method according to claim 1 wherein the contained food product is grape wine.

3. A method according to claim 1 wherein the food product is contained in a bottle.

4. A method according to claims 1 wherein the pouch is gas-flushed with carbon dioxide after vacuumization.

5. A package for extending the shelf life of oxygen-sensitive contained food products comprising: a) a heat-sealed pouch comprising a polymeric material and having an oxygen barrier layer; and b) a vacuumized, inert gas-flushed interior of said pouch containing the contained product and an oxygen scavenger.

6. A package according to claim 5 wherein the pouch comprises" a multilayer film including a layer of ethylene vinyl alcohol copolymer. I ^ ,—• 22 2 8

7. A package according to claim 5 wherein the interior of the pouch is gas flushed with carbon dioxide.

8. A package according to claim 5 wherein the product is contained in a bottle. 5 9. A package according to claim 8 wherein the bottle is constructed of a material taken from the group consisting of polyethylene terephthalate, glass, and multilayer laminates.

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J 10. A method as claimed in any one of claims 1-4 substantially as hereinbefore described.

11. A package as claimed in any one of claims 5-9 substantially as hereinbefore described. o Q DATED THIS' ^ DAY OF CteffcJW! EXLV |9 7 A. J. PARK & SON PER AGENTS FOR THE APPLICANTS -4DECI987.;;,1