US2724650A - Packages and packaging articles - Google Patents

Description

United States Patent 2,724, 50 PACKAGES AND PACKAGING ARTICLES Daniel Melnick, Teaneck, N. 1., assiguor to The Best Foods, Inc., New York, N. Y., a corporation of New Jersey No Drawing. Application July 18, 1952,

, Serial No. 299,761

11 Claims. (Cl. 99 179) The present invention relates to protective packaging and wrapping material and more particularly to protective wrapping and cartoning material for protecting oleaginous foods which are ordinarily solids at room temperatures from fungus and bacterial contamination. The protective packaging materials of the invention are most suitable for use as parchment wrappers and waxed cartonsfor packaging margarine and butter.

It is an object of the present invention to provide a protective wrapping material which will prevent oleaginous food materials, anddesirably oleaginous-aqueous materials which are normally solids at room temperature, such as the bread spreads: butter and margarine, from becoming contaminated by molds under the most adverse conditions of storage. A

It is a further object of the present invention to provide a wrapping and cartoning material impregnated with a fungistatic composition which is easily applied and will protect the contents from external fungus contamination.

It is an additional object of the present invention to provide a fungistatic wrapping and cartoning material which will successfully protect the wrapped contents from external fungus contamination without direct incorporation of a fungistatic agent into the packaged contents themselves. It is also an object to provide wrapping material which will not impart more than infinitesimal and incidental amounts of fungistatic agent to the wrapped contents.

Mold contamination of bread spreads, including butter and margarine, is a serious problem facing the processing industry and the retail distributor. When mold contamination of a bread spread is discovered, the consumer is justified in returning the product. This results in not only a costly problem for the manufacturer but must inevitably result in some damage to his reputation. Quite frequently, entire batches of product of the same code number are returned, even though the incidence of mold spoilage in those batches wassmall. Upon the return of moldly prints, it is not possible to segregate the moldy prints from the uncontaminated ones; for while it is possible to subject the individual prints to visual examination, the unaffected prints may not be salvaged since the product must be stripped of its wrapping as part of the examination. Even if no visual signs of contamination are found, it is not possible to re-wrap and package these prints since they have been exposed to the air and may be subject to new contamination or they may already be infested with an early stage of mold growth which is not detectable upon visual examination.

While bread spreads, such as butter and margarine, are processed under the highest conditions of cleanliness by reputable manufacturers, these products are not sterile. Regardless of how microbiologically clean the butter or margarine may be as a result of manufacturing cleanliness, the product may still become contaminated after packaging. Under conditions of variable, uncontrolled humidity and elevated temperatures, such as may result in retail outlets, oil staining of the carton may occur.

This is due to the melted oils or fats in the bread spread leaking through the parchment wrapping and dissolving the parafiin coating of the carton itself. After the paraf fin coating has been dissolved in the oil exudate, the exposed cellulosic material of the carton becomes a good medium for the propagation of airborne molds settling upon it. The inner wrapper also made of cellulosic materials is in itself a good medium for supporting mold growth, even in the absence of oil leakage from the product. These molds can work their way into the product, primarily through the overlap of the inner wrapper.

While mold contamination is not a particularly pressing matter where proper storage facilities are available, bread spreads, such as margarine and butter, are often subjected to abusive treatment during retail distribution. In fact, it is only the most highly progressive retail outlets which have suflicient refrigeration facilities to protect the large quantities of butter and particularly margarine which pass through their normal sales channels. It is not uncommon to find large quantities of material placed on open unrefrigerated shelves in retail outlets. During the summer months, this material may be subjected to temperatures far in excess of the melting point of the lower-melting constituents of the oleaginous component. The resulting oiling o with or without accompanying weeping (moisture separation) makes the butter or margarine highly susceptible to external contamination from molds.

Bread spreads, such as butter and margarine, are characterized by a high minimal fat content of about They also contain an aqueous phase containing non-fat, milk solids. Salt is very frequently added in an amount up to 3.5% of the total weight of the bread spread for flavor purposes and particularly as a protective measure against mold and bacterial spoilage of the product. Be-

cause of the nutrient aqueous phase of these bread spreads, molds can grow on these products. With a total salt content which usually ranges from 2.0 to 3.5%, which is equivalent to 13 to 23% of the aqueous phase, a partially effective means of inhibiting mold growth on butters and margarine is provided. The use of salt, plus the observance of. satisfactory processing conditions and proper refrigeration of the product before and after packaging, should assure these products of freedom from visually detectable mold contamination. Nevertheless, due to the faulty storage practices in a large number of retail outlets, mold contamination is quite frequent and consumer complaints of moldy butter and margarine are common. For the above reasons, the incorporation of salt in the product is not in itself a satisfactory remedy to overcome this difficulty. Molds are salt-tolerant organisms which grow rapidly on a medium provided a high humidity, adequate oxygen supply, and optimal tem-. perature are maintained.

The bread spread industry has undertaken numerous measures, other than the use of salt, in an attempt to overcome mold contamination of the product. It is quite common for the manufacturer to add sodium benzoate to margarine up to an amount of 0.10% by weight of the total product as permitted by law. Butter is usually not so treated. This treatment is almost completely ineffectural. First of all, sodium benzoate in a margarine has no significant fungistatic activity; it is only when the benzoic acid is available as the free acid that any protective effect is. to be noted. In present day practice, margarine is made from non-cultured milk having a pH of the aqueous phase of approximately 6.5. The butter .manufacturers attempt to adjust the pH of the aqueous phase as near to neutrality as possible (pH 6.7 to 7.2). At these high pH values, very little, if any, free benzoic acid is liberated from the sodium salt. Accordingly, although the practice of using sodium benzoate is Widespread, its effect is primarily psychological and its value substantially nil.

One approach to the problem which has been reasonably successful, has been wrapping of the prints of bread spread with an aluminum foil wrapper having a parchment backing. This wrapper containing an aluminum outer surface is substantially impermeable to air and thus the growth of molds on the inner parchment surface or on the product itself is made difficult. However, oil staining of the carton may still occur, even with aluminum foil, due to oil leakage at the folds or by the funneling of the oil through pinholes in the foil. Although reasonably successful, aluminum foil wrapping, because of its considerable cost, is not a satisfactory solution of the problem facing this highly competitive industry, and adds to the cost to the consumer of the product.

Cellophane overwrapping of the carton (with a parchment inner wrapping) has been attempted but this is I not only valueless but actually increases the susceptibility of the product (or more properly the package) to mold spoilage. Not only will cellophane itself support mold growth but it also serves as a barrier to moisture transfer, thereby insuring a high humidity within the package at all times. The use of cellophane thus makes the product more susceptible to mold contamination.

Attempts have been made to solve the problem of moldy butter and margarine by treating the wrapping and packaging materials with a fungistatic material. It has been recognized that mold growth initiates primarily on the surface of the butter or margarine print, where there is an available oxygen supply, rather than in the body of these prints. In margarine containing 0.1% benzoic acid or sodium benzoate, very little of the fungistatic material is at the surface of the print where protection is required. That material within the body of the print is wasted for all practical purposes. Other investigators have treated the inner surface (that facing the margarine) of the wrapper with an aqueous or alcoholic solution of benzoic acid or sodium benzoate. Tests of the products wrapped with these wrappers show that no fungistatic activity had been imparted to the wrapper and no protection was provided for the product. In the course of drying the wrappers, it appears that the benzoic acid had completely volatilized and this was not appreciated by the prior art investigators. Sodium benzoate will remain on the wrappers but due to the high pH of present day margarine and butter, this material will not liberate free benzoic acid and thus provides nomeasurable fungistatic activity.

It is apparent that the prior art was concerned with placing fungistatic material in direct contact with the surface of the print. Efforts were directed entirely toward placing as much of the fungistatic agent as possible in contact with the surface of the product.

The present invention comprises a cellulosic material suitable for use as a packaging material coated with a wax of a melting point of between 125 and 165 F. wherein the wax contains not more than 2% of an edible, fat soluble, steam-distillable, organic carboxylic acid.

The desirable packaging materials for use in the invention are in the nature of parchment wrappers (which may be wrapped around a print of butter or margarine) and wax coated, stiff, paper board which may be used as a cartoning material. While satisfactory results are obtained with a brittle wax of a melting point of 125 to 165 F., preferred results are obtained with a wax having a melting point of 135 to 155 F. It appears that waxes providing optimum results are those having a melting point of approximately 140 to 150 F.

The preferred coating waxes are the refined paratfin waxes. This type of material, sometimes called block paraffin, is a purified mixture of high melting, crystalline hydrocarbons derived from petroleum. Hydrogenated vegetable or glyceridic oils have also been found successful and it is intended that the term waxes, as used t the mechanics of packaging the bread spreads.

he to :3. in this specification and claims, shall include'hydrogen ated vegetable oils. Where a hydrogenated vegetable oil is used, it is preferred that the iodine number of the oil be a value of 3 or iess. Hydrogenated vegetable oils having an iodine value in this range show less flavor or odor deterioration on standing and are thus more desirable from the esthetic standpoint. Oils having a higher iodine value, on the other hand, are no less satisfactory from the standpoint of fungistatic protection of the packaging material. The socalled microcrystalline waxes derived from petroleum may also be used, but as a diluent for the paraflfin (macrocrystalline) waxes or of the hydrogenated vegetable oils. The microcrystalline waxes are solid hydrocarbon mixtures of a molecular weight averaging higher than the paraffin waxes and possess plastic and adhesive properties. These plastic properties are desirable to prevent cracking of the wax coating at the folds of the packaging material. it is believed that the microcrystalline waxes function as a plasticizer. Amounts of from 10 to 20% of the total wax material may desirably be a microcrystalline wax. Blocking, the sticking of cartons or wrappers one to the other, results more frequently when the microcrystalline waxes are used exclusively as the coating material. It is contemplated that various other plasticizers may be used to provide certain physical properties, such as lustrous finish as provided by polyethylene, and still remain within the scope of the present invention. The melting point of the wax referred to above is that of the wax including any plasticizer which may be incorporated.

It has been customary for the packaging industry to supply the food processor unwaxed parchment and waxed cartons for packaging bread spreads, in the latter case, the parafiin wax has a melting point of 128 to 130 F. These waxes with lower melting point are objectionable in that limpid oil separating from the butter or margarine produces excessive oil staining of the packaging materials. Products in such oil soaked wrappers have little sales appeal and may be further penalized by supporting mold growth. These lower melting parafiins also have a greater tendency for blocking. This blocking" or sticking of one Wrapper unit to its neighbor occurs particularly in the summer months and it may interfere with It has been discovered that the fungistatic acids of the invention may be readily released from these low melting waxes to protect the bread spread but the advantages so gained are outweighed by the disadvantages described above. Waxes melting above 165 F. are undesirable since the release of the fungistatic acids of the invention occurs to a very limited degree, thus hindering their effectiveness. Furthermore, the higher melting waxes require the use of much higher temperatures in coating the wrapping materials which results in excessive volatilization of the fungistatic acids during the coating operation. The final objection to higher melting parafiin waxes (above 165 F.) is the greater tendency for such waxes to crack at the folds of the packaging material and to even flake off.

Waxes having a melting point of between and 155 F. provide preferred results. These waxes are substantially free from the disadvantages discussed above relative to those waxes melting below 125 or above 165 F. Waxes melting between 135 and 155 F. are particularly valuable and critical in providing a packaging composition which Will provide practical fungistatic protection to the package and, therefore, the bread spread contents. Where paraffin waxes are employed, the preferred melting point range is between 135 and 165 F. If hydrogenated vegetable oils are used, the preferred melting point range is between 125 and 155 F. Optimum results are obtained in all cases where the wax has a melting point of between and F.

The fungistatic acid dissolved in the wax is an edible, fat soluble, steam-distillable, organic carboxylic acid.

Conterhplated as desirable acids for use in the invention are those havingunsaturation next to the carboxyl group in accordance with the following formula:

R1 Rs tw) R1-.(, --C.OOH That portion of the moleculecontaining the unsaturation may be either an aliphatic or aromatic hydrocarbon group. Where more than one unsaturated group exists, such unsaturation shall be part of a conjugated double bond system with the alpha-beta unsaturation. In the formula given above, R1 is hydrogen, when R2 and Rs combine to complete a single carbocyclicnucleus; R1 is carbon of an aliphatic group when R2 and Rs are hydrogens. Examples of such acids are: crotonic, isocrotonic, alpha-hexenoic, benzoic, sorbic and para-hydroxybenzoic acids. Thepreferred acids according to the invention are benzoic, para-hydroxybenzoic, sorbic and alphahexenoic acids. Benzoic and sorbic acids are the most suitable. r

The fungistatic acids are to be incorporated in the wax coating of the outer carton and/or the inner parchment wrapper in an amount of not more than 2% by weight of the wax coating and preferably: between 0.5 and 1.0% by weight. It is possible to dissolve some of the acids in the melted waxes in much higher concentrations, viz., 5% in the case of benzoic and sorbic acids. However, on cooling these wax solutions, crystals of the fungistatic acids are deposited on the wax surface. A wrapper containing readily detectable crystals in the wax coating is objectionablein appearance. At a 1.0% con-. centration, no crystalline deposits are to be noted. Since as much as 50%. of the fungistatic acid may be volatilized during the coating of the packaging material with the wax, the preferred initial concentration of acid in the heated wax solution is 1.0 to 2.0%. Another disadvam tage of excessively high concentrations of fungistatic acid in the wax coatings is the medicinal odor imparted to the packaging material. Above 2.0% concentration, the odor becomes objectionable and may adversely condition a customer toward the product. 1

Due to the volatility of the fungistatic acids which are incorporated into the waxes in the present invention, loss of as much as 50% of the, acids may occur during the coating operation. However, by observing precautions and following the process of the invention for incorporating the waxes upon the packaging materials, this loss may be conveniently reduced to about 25%. The waxes containing thefungistatic acids are prepared for coating by dissolving an amount of the acid up to 2% in the wax by stirring and heating in the wax. "It is advisable not to exceed the melting point of the wax by more than about F. It is also advisable that the temperature of the wax bath not exceed the melting point ofthe wax by more than 10 F. during the coating operation. The

wax may be applied to the wrapping materials by either of two methods. The first of these is the so-called dry waxing procedure. a This method is essentially impregnationof the absorbent paper stock with the wax containing the fungistatic acid so as to fill up the minute spacings between the fibers of the paper with wax. In this process, only a small portion of wax remains as a surface coating. The second process isthe so-calledfwet waxing process. The wax is applied as a continuous film with a relativelysmall portion of the wax impregnating the paper stock. Either of these procedures are well known to the paper coating art and the term wax coating, as used in this specification, is intended to include both procedures for applying the wax to the packaging materials. If unnecessarily high temperatures are maintained during the coating operation, such as a temperature in excess of 175 F. or a temperature more than 10F. above the melting point of the wax, excessive volatilization of the acid will result. For example, at a 212 F., all of the fungistatic acids to be used in accordance with the invention are largely volatilized during the coating operation. Sorbic and hexenoic acids are more readily sublimed from the heated waxes while benzoic acid is more readily retained by the wax. When a temperature of 170 F. is used, a wax-holding period of no longer than four hours and preferably one of less than two hours is employed, i. e., a maximal period of four hours for the progressive addition to the trough of the same quantity of wax at the start of the operation, keeping the wax in the coating trough at a constant level during this period. The treated packaging materials normally suffer no further loss in fungistatic acids under their customary conditions of storage. The cartons are usually stored in stacks while the wrapping papers may be stored both in the form of stacks or in rolls. If the packaging materials are exposed as individual cartons or wrappers and subjected to circulating air at F. for a period of four weeks, an additional loss of 25% of the fungistatic acids is suffered. Such conditions represent the practical extreme in deleterious conditions to which packaged butter or margarine may be exposed in normal distribution.

The essence of the present invention, which is novel to the packaging and food industry, is the protection of the packaging material from fungus atack and only indirectly protection of the product itself. Butter and margarine may be processed under conditions of utmost cleanliness, so that the resulting product may be made microbiologically clean (although not sterile). These products will be so free of mold that they will exhibit in accordance with prior art teachings, is exposed to abusive storage conditions (absence of refrigeration), the product and package becomes susceptible to mold contamination and growth. The resulting mold propagation may progress to such a degree that even should the product be returned to proper conditions of storage, the mold growth will be so apparent that consumer rejection of the product will follow. As distinguished from the present invention, the prior art was directed to attempts to bring a fungistatic agent on the wrapper surface into intimate contact with the surface of the product and/or to admix the fungistatic agent with the product itself.

As a result of the present invention, there is made available a dynamic protection against mold contamination in the marketing of bread spreads. The fungistatic acid is held in reserve until conditions arise wherein they are needed to combat fungus growth. Both margarine and butter are made to melt in the range of to F. so that they will promptly dissolve in the mouth of the user and have desirable mouthing properties. Because the fat of these bread spreads is made up of a mixture of a large number of difierent triglycen'des, these products will tend to exude the lower melt.- ing oils when they reach 75 to 80 F. This separated oil fraction remains liquid at room temperature. A packaged bread spread is not in jeopardy of becoming mold contaminated until these lower melting oils are released from the product. It is normally only when these lower melting oils seep through the Wrapping and reach the wax carton that danger exists. Theseparated oil is a solvent for the wax coating on the packaging materials. Since elevated temperatures of storage are necessary forthe melting of these oils, oil separation is apt to occur only under poor conditions of storage. Also, under these conditions, optimal temperatures are provided for mold propagation on the packaging materials. It is under these unfavorable conditions of storage that the packaging compositions of the present invention come into play. Since the wax coating contains fungistatic acids which dissolve in the oils, the fungistatic 75 agent is liberated from the wax by the separated oil and thereby creates a medium unfavorable for mold propagation. Thus, the fungistatic acids in the wax coatings are not released under proper storage temperatures (55 F. or less at which temperature mold growth is nil), and it is only when the acids are needed that they are released from the packaging coating.

Packaging materials in accordance with the present invention have been tested under various conditions of adverse storage and have been found to be highly successful in'protecting the wrapped product from mold contamination. The tests which will be described demonstrate the various advantageous properties of the packaging compositions of the present invention.

It is essential to the satisfactory performance of the treated packaging compositions of the present invention that the reservoir of fungistatic acid shall not be unduly depleted during manufacture of the packaging material or during satisfactory conditions of storage but will readily supply adequate quantities of fungistatic acid at the time when oil separation occurs from the butter or margarine due to adverse conditions of storage. It is necessary that the acid used and the wax in which it is dissolved shall cooperate to function properly at the required time with the oils separating from abused margarine or butter. It has been discovered that when the fungistatic acids described in accordance with the present invention are dissolved in wax having a melting point within the range present invention, into the oil fraction which separates from margarine at 80 F. Tests were conducted in accordance with the following procedure: Twenty gms. of'

parafiin wax or hydrogenated vegetable oil containing 1.0 per cent of a fungistatic acid (sorbic) were melted and poured into a stainless steel pan of 22 cm. by 22 cm. After uniform distribution of the molten wax over the bottom surface, the pan was placed in a brine bath and chilled rapidly; this simulates the coating of wrapping ma terials. The hardened wax was then scraped ofi yielding flakes 0.5 to 0.75 mm. thick. 1.25 gms. of these flakes were placed in 100 ml. beakers and 48.75 gms. of limpid oil separated from margarine at 80 F. were added. (This oil had a melting point of 82.8 F. and an iodine value of 75, whereas the original margarine oil had a melting point of 95 F. and an iodine value of 70.) These test systemswere held at 80 F; and the oil free of flakes periodically analyzed for-sorbic acid content. The concentration of this fungistatic acid determined spectrophotometrically (maximal absorption at 255 millimicrons) was used as an index of wax dispersion or solution. The proper blank controls were included in the analyses. The experiments were designed tosimulate the exposure of the wax coatings to the oil drippings from the bread spreads during abusive storage of the packaged products in retail outlets. The results are shown in Table I which follows:

TABLE I Solution of wax and fungistatic acid (sorbic acid) in the oil fraction separated from margarine at 80 F.

Solution of Wax and Sorbie M P of Acid in Oil at 80 F. aiter- Maiga'rme Melting Iodine Fraction Wax P omt, Value 1 Day 4 Days 12 Days after 12-day Percent of added wax and 2 2 sorbic acid dissolved 127 0 75 100 100 83. 5 137 0 57 64 67 83. 8 154 0 27 5O 57 84. 6 Do 165 0 15 84. 6 Hydrogenated peanut oil 120 44 51 71 71 84. 0 Hyidrogenated cottonseed 139 1 6 0 3 8 48 63 8 4 Hydrogenated soybean oil. 152 1 10 35 42 86. 2 Miergerystallinen 0 26 84 91 84. 8 0 0 18 35 48 84'. 7 Do 172 0 12 21 26 84. 2

1 Melting point of margarine oil fraction was 828 F. prior to the-addition of 48.75 parts of the oil to 1.25 parts of wax.

called for by the invention, they are not available to exhibit fungistasis according to conventional tests. For we ample, when 1% of sorbic acid dissolved in a hot (140 F.) paraffin wax having a melting point of 130 F. is coated upon the walls of a flask and cooled, exposure to water showed that none of the sorbic acid is extractable by the water. This would appear to be disappointing since sorbic acid has even a greater distribution ratio (concentration of acid in the aqueous phase to concentration of acid in the oil) than benzoic acid in the two phase system found in butter and in margarine. In conventional plating tests in which parafiin scales prepared from paraflin' solutions containing 1% benzoic acid or 1% sorbic acid were placed on wort agar plates and the surface of the agar plates streaked with a mixed mold inoculum and incubated at 80 F. for a period of five days, no Zones of inhibition around the paraflin scales were noted, although no growth on the scales themselves was observed. The inoculum used in this test and elsewhere in the specification is a mixture of the common molds isolated from salted margarine and butter returned from the trade because of mold spoilage.

Contrary to the findings by the conventional tests, it was discovered that sorbic acid will be released from the wax solutions, prescribed for use in accordance with the r unsightly oil-stained very quickly.

scribed by the present invention, the' fungistatic acids are more readily released but the waxes are then prone to cause blocking, the sticking of one carton or wrapper to its neighbor during packaging. The packaging materials coated with waxes of undesirably low melting points are too sensitive to attack from the separated oils, becoming The hydrogenated vegetable oils are superior to the paraffin waxes of comparable melting point in that similar results may be obtained with hydrogenated vegetable oils of significantly lower melting point. That true solution of the wax in the margarine oil fraction occurred is apparent from the increase in melting point of the oil on completion of the test(see last column of Table I). The failure to observe progressive increase in the melting point of the margarine oil fraction on exposure to the wax of progressive higher melting points is due to the progressively lower degree of solubility of the wax of higher melting point.

I The extent of t olatilization of the fungistatic acids 1 from the heated wax solutionsare illustrated in two tables for two of the. fungistatic acids are illustrative of the findings in the series.

TABLE II 10 to a higher degree. At 170 F., whichis'the ayerag' temperature of the wax in coating operations, aholding period of no longer than four hours, and preferably of less than two hours, should be observed, i. e., a maximal period of four hours for the progressive addition to the trough of the same quantity of wax at the start of the operation, keeping the wax during this period at a constant level in the trough. As an alternate or added safety measure the temperature of the heated wax should be maintained not at 170 F. but at about 10 F. above the melting point of the selected Wax. At the more moderate coating temperatures the hydrogenated vegetable oils are superiorto the paraffin waxes in favoring benzoic acid retention. This is not noted atthe high Volatilization of benzoic acid from waxes held at elevated temperatures Hours at 140? F. Hours at 170 F. Hours at 212 F.

Wax 3" 2 4 a 24 2 4 o s 1 2 3 Percent loss of Benzoic Acid Paraffin 127 8 16 63 21 67 76 95 11 38 69 Do. 137 4 10 58 29 44 69 8 35 68 154 6 9 14 3 14 31 31 t 49 70 16 28 50 165 5 7 1 2 1 13 i 59 83 14 65 Average 1 2 9 13 61 24 39 57 79 12 34 63 Hydrogenated peanut 011.. 120 0 0 13 13 3 13 35 60 14 39 65 Hydrogenated cottonseed oil 139 1 4 5 24 2 11 24 50 14 24 54 Hydrogenated soybean oil 152 7 11 15 2 24 15 20 34 61 I 8 30 Average -L. 1 2 9 19 7 15 31 57 12 31 53 1 In calculating the averages for all waxes, the results at 140 F. onthe unmelted wax flakes were omitted.

. 3 Wax flakes not melted.

TABLE III Volatilization of sarbic acid from waxes held at elevated temperatures Hours at 140 F.

Hours at 170 F.

Hours at 212 F.

Wax 15" 2 s 24 Percent loss of Sorbic acid Average 1 Q. 7 22 25 66 Hydrogenated peanut oil 120 a 10 10 14 40 Hydrogenated cottonseed oil.. 139 i 5 7 14 27 Hydrogenated soybean oil 152 0 0 8 z 8 Average 8 9 14 34 1 In calculating the averages for all waxes, the results at 140 F. on the unmelted wax flakes were omitted.

1 Wax flakes not melted.

The above results are important in demonstrating that precautions must be exercised in preparing the fungistatic wrapping materials of this invention. The. wax in the troughs through which the carton board or parchment are passed in plant coating operations must not be excessively heated. At 212 F., all the fungistatic acids selected for inclusion in the wax coatings are very volatile. Sorbic and hexenoic acids are more readily temperature (212 F.) or in tests with the more volatile fungistatic acids.

Wrappers and cartons coated with a waxcontaining a fungistatic acid in accordance with the present invention and produced on a commercial scale of operations, were subjected to other tests to evaluate their efficacy in preventing mold contamination.

The following data indicated in Tables IV and V lost from the heated Waxes, whilebenzoic acid is retained below shows the protection against mold growth granted by the packaging compositions according to the present spread itself rather than on the outer surface of the invention: parchment. Measurable inhibition of mold growth was TABLE IV Fungistatic properties of parchment wrappers before and after processing according to the present invention Mold Growth on Inocu- Parchment Example Melting Benzoic W on latcd Wrappers l I Point Acid in m i I Gig/lax, Wax lief- Perlgnt Alt 3 Aft e v C811 9! 61 No. Description Weeks Weeks Regular, Unwaxed l l Waxed on both surfaces" 139 0 0 32 .do 150 0. 0 29 l Waxed on one surface. 139 0. 94 18 none Waxed on both suriaces. 139 O. 57 32 none Waxed on one surface. 150 1.45 17 none Waxed on both surfaces 150 0. 90 29 none 1 Parchment sheets were inoculated on both sides with a mold-in-water suspension; the sheets were dried and then incubated at 80 F. at 100% relative humidity. Relative mold growth is indicated by number of +s.

resistance to mold propagation. The presence of the 30 fungistatic acid renders the wrapper remarkably resistant to molds. Given time, molds will eventually grow on the wrapper coated with the fungistatic wax on one noted only in Examples 2 and 4, i. e., only in the case of the margarines in direct contact with the fungistatic wax. While coating both sides of the parchment may provide certain advantages in this respect, it is not an admirable practice in all respects; for not only does it introduce some fungistatic acid into the product, but it surface, but such growth is predominantly on the unwaxed surface. The susceptibility of the unwaxed surface to mold growth is of no practical concern since the objective of the present invention is the protection of the microbiologically clean product through protection of the package from contamination by adventitious molds during retail distribution and sale; the waxed coating would be on the parchment surface away from the product. for mold growth than parchment, when these wrappers the manufacture of the bread spread.

Tests were conducted on waxed cartons prepared according to the present invention. The cartons were waxed on both surfaces. Earlier tests had demonstrated that the regular waxed carton is a far poorer medium TABLE V Fungistatic properties of parchment wrappers before and after processing according to the present invention in protecting bread spread and package 1 Parchment Example Mold Growth 1 After 3 weeks After 6 weeks No. Description On gg On On 3.2 On Carton men; Product Carton ment Product Regular, Unwaxed none Waxed on both Surfaces (wax=139 F., M. 1 none Waxed on both surfaces (wax=150 F., M. P.) none Waxed on one surface (wax=139 F., M. P.; 0.94% none none none i benzoic acid). Waxed on two surfaces (wax=139 F., M. P 0.57% none none none none none none benzoic acid). Waxed on one surface (wax=150 F., M. P.; 1A5% none none none i benzoic acid). Waxed on two surfaces (wax=l F., M. P.; 0.90% none none none none none none benzoic acid).

1 Illustrated with packaged margarine containing no fungistatic agent and stored at F. at relative humidity. Mold inoculum applied on parchment surface facing regular waxed carton; relative mold growth is indicated by the number of s.

The effectiveness of the present invention is well ilalone are inoculated and stored under conditions oplustrated by the above results. Tests were also contirnal for mold propagation. Accordingly, the cartons ducted with the mold inoculum applied to the bread 75 were tested before and after staining with margarine oil.

implicitly condones or permits insanitary practices in static acid, benzoic as such or as sodium benzoate, may be i i Y t 14 l I Typical results with benzoic acid as the fungistatic agent of acid in the wax, the quantity is exceedingly small, only in the Wax coating are shown in T able VI which follows:

Fungistatic properties of waxed cartons before and after processing according to the present invention 1 Cartons were inoculated on both sides with a mold-ln-water suspension; the cartons were dried and then finleubated at 80 F. at 100% relative humidity. Relative mold growth is indicated by the numer s.

The above data are typical of observations made on products in commercial channels. Oil stainingof cartons is practicallyalways a prerequisite for molds to grow on The tgfg i g g fi ig gagigg for 1 pound of the the cartons. Confirmatory results in tests conducted on bread spread gm 2:27 packaged margarine subjected to mold spoilage are pre- Weight wrapper of this inventim (1% sented in Table VII. The protective influence of the carpackaging materials are presented:

fungistatic acid in the wax coating of outer surface) gm 2.67

tons of this invention on the untreated parchment wrap- Weight t Weight of funglstatic acl agm 0.004 p r w al o pp r n l these tests- 3 Then, the concentration of fun c acid in r relation to product packed "per cent 0.0009

TABLE VII Fungistatic properties of waxed cartons before and after processing according toj the present invention in pro-- tecting bread spread and package 1 Carton Example Fungi- Mold Growth 1 After 6 weeks Melting static Wax Point of Acid on N D ri a i w gmoni 0 i P h 0- BS0 p OD. 3X 010611 ar on are i Percent ment Product Oontrol Regular. waxed 130 0.0 15.2 5 Benzoic acid in w 137 1. 0 15. 6 none none -do 142 0.57 15.5 none Sorbic acid in wax. 142 0. 14. 2 none illustrated with margarine contaimn g no tungistatic agent wrapped in regular parchment and stored at 80 F. at 100% relative humidity.

fit Told inoculum applied on both carton surfaces; relative mold growth is indicated by the number 0 s. l

Poolin both develo ments i. e. ache in the bread The ton:

g p p g g Weight of regular waxed carton for 1. pound of spread in both the fungistatic wrappers and in the fungistatic cartons of this invention, imparted further resistance of the packaged product to mold spoilage. Under each circumstance no mold growth, despite deliberate inthe bread spread gm 21.50 Wax coating of both inner and outer surfaces c per cent" 15.0 Weight of wax coating gm 3.22 Weight of fungistatic acid (1% of the wax) oculations occurred on the acka in materials or on the 0-032 bread spread after 6 to 8 w e eks gorige at 80 F. and. at $311533 i fifiiiifici idfi fifif ii cr ficff 0.007

100 per cent relative humidity. In these tests objectiontfg gg igg gfg fgg fungistatic acid in mm able oil staining of the packaging material was apparent tion to product packed per cent 0.008

When the parafiin waxes of melting point of less than 130 F. or the hydrogenated vegetable oils of fmelting point less than 125 F. were used for the coatings. Use of high melting coatings above 165 F., was abandoned because of flaking difiiculties and interference with machine operations due to the poor flexibility of the wrapping materials.

The preferable concentrations of fungistatic acid of 0.5

It is to be emphasized, however, that the objective of the present invention is not to furnish fungistatic acids to the bread spreads. The present invention is intended to protect the packaging materials against mold spoilage, the ordinary packaging materials having been shown to support mold growth as received or after having been in to 1.0 P cent in Wax coating of the packaging contact with the bread spreads duringabusive conditions terials for butter or margarine might be considered by of storage i analyses of margarmes and Butter frefi food technologists to be a very high concentration, since 'f funglstauc afuds and stored at -80 for a in one of the two bread spreads (margarine) the fungi period of one month in the above wrappers have shown no detectable amounts (less than 0.00001%) of either added in a maximal concentration of only 0.1 per cent. bellloic acid in the bread P Thatthe However, in terms of absolute amount of fungistatic acid in Products Were abused during Storage was pp from relation .to product furnished by the higher concentration 75 the oil stained condition of the wrapping materials.

one-twelfth of that ordinarily in the product. For purpose of illustration, the results calculated for two typical Analyses of the surfaces of the bread spreads, 1.0 mm. in depth, adjacentto. the oil stained areas of the package,

also have shown no detectable amounts of either fungistatic acid in the products; this latter analytical approach is a far more critical test of the possible migration of fungistatic acid into the product.

' The terms and expressions employed are used as terms of description and not of limitation, and it is not intended, in the use of such terms and expressions, to exclude any equivalents of the features shown and described or portions thereof, but recognize that various modifications are possible within the scope of the invention claimed.

What is claimed is: V

1. A package comprising at least one print of a bread spread selected from the class consisting of butter and margarine, said print being protected from fungus contamination by being wrapped in a cellulosic wrapper, said cellulosic material being susceptible to fungus contamination; said wrapper being coated on the exterior surface only with a Wax having a melting point of between 125 and 165 F. and containing therein not more than 2% of a fungistatic edible, fat soluble, steam-distillable, organic carboxylic acid having unsaturation adjacent to the carboxyl group and that portion of the molecule containing the unsaturation is a member selected from the class consisting of aliphatic and aromatic hydrocarbon groups and groups containing an additional unsaturated linkage making up a conjugated double bond system with the unsaturation adjacent to the carboxyl group.

2. A package comprising at least one print of a bread spread selected from the class consisting of margarine and butter, said print being protected from fungus contamination by' being wrapped in a parchment wrapper coated on the exterior side only with a wax and the wrapped bread spread packed in a carton of cellulosic board coated on both sides with a wax; each of said waxes having a melting point of between 125 and 165 F. and containing uniformly dispersed therein a fungistatic edible, fat soluble, steam-distillable, organic carboxylic acid having unsaturation adjacent to the carboxyl group and that portion of the molecule containing the unsaturation is a member selected from the class consisting of aliphatic and aromatic hydrocarbon groups and groups containing an additional unsaturated linkage making up a conjugated double bond system with the unsaturation adjacent to the carboxyl group.

3. An article comprising an oily exudable print selected.

from the group consisting of butter and margarine containing a cellulosic wrapper thereabout which is susceptible to fungus contamination, said wrapper containing on the outer surface thereof only a coating of wax having a melting point of between 125 and 165 F., and said wax coating being susceptible to the solubilizing eifects of any exuded oil from said print and containing not more than about 2% of a'fungistatic edible, fat soluble, steam-distillable, organic carboxylic acid having unsaturation adjacent to the carboxyl group and that portion of the molecule containing the unsaturation is a member selected from the class consisting of aliphatic and aromatic hydrocarbon groups and groups containing an additional unsaturated linkage making up a conjugated double bond system'with the unsaturation adjacent to the carboxyl group.

4. A packaging article for a bread spread selected from the class consisting of margarine and butter comprising a cellulosic material coated with a wax of melting point of between 135 and 155 F. which contains therein not more than 2% of an edible, fat soluble, steam-distillable, organic carboxylic acid having unsaturation adjacent to the carboxyl group and that portion of the molecule containing the unsaturation is a member selected from the class consisting of aliphatic and aromatic hydrocarbon groups and groups containing an additional unsaturated linkage'making up a conjugated double bond system with the unsaturation adjacent to the carboxyl group.

5. A packaging article for a bread spread selected from the class consisting of margarine and butter comprising a cellulosic material coated with a wax of melting point of between 135 and 155 P. which contains therein not more than 2% of an edible, fat soluble, steam-distillable, organic carboxylic acid selected from the class consisting of benzoic, pa rahydroxybenzoic, sorbic and hexenoic acids.

6. A cellulosic material susceptible to mold attack suitable for use as a parchment wrapper and a carton for packaging butter and margarine, said cellulosic material being coated with a wax of melting point of between and 165 F. and containing therein not more than,2.0% of an organic carboxylic acid selected from the class consisting of benzoic, parahydroxybenzoic, sorbic and hexenoic acids.

7. A. cellulosic material susceptible to mold attack suitable for use as a parchment wrapper and a carton for packaging butter and margarine, said cellulosic material being coated with a hydrogenated vegetable oil of melting point of between 125 and 155 F. and containing therein not more than 2.0% of an organic carboxylic acid selected from the class consisting of benzoic, parahydroxybenzoic, sorbic and hexenoic acids.

8. A parchment wrapper for wrapping butter and margarine, said parchment being coated on one side only with a wax of melting point 125 to 165 F., said wax containing therein not more than 2% of an edible, fat soluble, steam-distillable, organic carboxylic acid having unsaturation adjacent to the carboxyl group and that portion of the molecule containing the unsaturation is a member selected from the class consisting of aliphatic and aromatic hydrocarbon groups and groups containing an additional unsaturated linkage making up a conjugated double bond system with the unsaturation adjacent to the carboxyl group, said coated side of said parchment being intended to appear on the outer side of a wrapped package.

9. A parchment wrapper for wrapping butter and margarine, said parchment being coated on one side only with a wax of melting point to B, said wax containing. therein 0.5 to 1.0% of a fat soluble, steam-distillable organic carboxylic acid selected from the class consisting of benzoic, parahydroxybenzoic, sorbic and hexenoic acids; said coated side of said parchment being intended to appear on the outer side of a wrapped package.

10. A cellulosic material susceptible to mold attack suitable for use as a wrapper for packaging a bread spread selected from the class consisting of butter and margarine,

said cellulosic material being coated on one side only with ing unsaturation adjacent to the carboxyl group and that portion of the molecule containing the unsaturation is a member selected from the class consisting of aliphatic and aromatic hydrocarbon groups and groups containing an additional unsaturated linkage making up a conjugated double bond system with the unsaturation adjacent to the carboxyl group.

ll. A cellulosic material susceptible to mold attack suitable for use as a wrapper for packaging a bread spread selected from the class consisting of butter and margarine, said cellulosic material being coated on one side only with a coating which is intended to appear on the outside when wrapped about the bread spread, said coating comprising a wax having a melting point of between 135 and 155 F.

and containing therein between 0.5% and 1% of an acid selected from the class consisting of benzoic, parahydroxybenzoic, sorbic and hexenoic acids.

(References on following page) References Cited in the file of this patent UNITED STATES PATENTS Mitchell Dec. 23, 1941 Ingie Aug. 4, 1942 Abrams et a1. May 9, 1944 Gooding June 26, 1945 Coleman et a1. June 28, 1949 Flett Aug. 23, 1949 Bennett Feb. 14, 1950 Coleman et a1 Sept. 4, 1951 Cherepow et a1. Aug. 5, 1952 18 FOREIGN PATENTS 555,907 Great Britain Sept. 13, 1943 110,841 Australia June 8, 1940 OTHER REFERENCES The Journal Textile Institute, 1930, vol. 21, pages T245 to T259, article entitled The Inhibitory Action of Certain Substances on the Growth of Mould Fungi, by R. G. Fargher et a1.

Claims (1)

1. A PACKAGE COMPRISING AT LEAST ONE PRINT OF A BREAD SPREAD SELECTED FROM THE CLASS CONSISTING OF BUTTER AND MARGARINE, SAID PRINT BEING PROTECTED FROM FUNGUS CONTAMINATION BY BEING WRAPPED IN A CELLULOSIC WRAPPER, SAID CELLULOSE MATERIAL BEING SUSCEPTIBLE TO FUNGUS CONTAMINATION; SAID WRAPPER BEING COATED ON THE EXTERIOR SURFACE ONLY WITH A WAX HAVING A MELTING POINT OF BETWEEN 150* AND 165*F. AND CONTAINING THEREIN NOT MORE THAN 2% OF A FUNGISTATIC EDIBLE, FAT SOLUBLE, STEAM-DISTILLABLE, ORGANIC CARBOXYLIC ACID HAVING UNSATURATION ADJACENT OT THE CARBOXYL GROUP AND THAT PORTION OF THE MOLECULE CONTAINING THE UNSATURATION IS A MEMBER SELECTED FROM THE CLASS CONSISTING OF ALIPHATIC AND AROMATIC HYDROCARBON GROUPS AND GROUPS CONTAINING AN ADDITIONAL UNSATURATED LINKAGE MAKING UP A CONJUGATED DOUBLE BOND SYSTEM WITH THE UNSATURA-TION ADJACENT TO THE CARBOXYL GROUP.