MULTIFUNCTIONAL, BIODEGRADABLE AND COMPOSTABLE FOOD CONTAINER, OPTIONALLY FITTED WITH AN ANTIMICROBIAL COATING

Technical Field

The present invention generally relates to convertible transportable containers and has been developed with particular reference to the containers for the disposable transport of food products.

Background Art

Convertible transportable containers are generally known. For example, take away foods - contained in their receptacles - can be provided in bags, which first enable the consumer to collect and transport the food, and then to facilitate its enjoyment. These solutions (see, e.g., GB2404181 A) typically involve the creation of a bag, formed from a sheet material, typically of paper material, which allows the food to be contained and transported. The sheet material is die-cut and provided with preferred folding lines, and is given a closed configuration by overlapping respective portions, which are secured together by means of restraint, such as adhesives, or adhesive tapes, or multiple folds. The sheet material that makes the structure of the bag can then be brought by the user to take on a substantially planar configuration, thus releasing the aforementioned means of restraint, so that it can serve as a placemat or the like. Convertible containers of this type are not particularly convenient, in relation to how they are used by the end users. For example, converting the bag to the “open” configuration involves awkward operations on the part of the user, often resulting in unwanted breakage or tearing of the sheet material, partially jeopardizing its usefulness as a placemat or the like. Even when in their initial configuration, in the form of a bag, the aforementioned containers have a structure that is often relatively fragile, and not without risk of breakage, for example at the handles, the very transportation of these containers can, in some cases, be not particularly convenient. The fragility of the paper materials used is drastically reduced by possible contact with liquids or the like, compromising their characteristics and increasing the risks of breakage: think of the accidental 2 spillage of a fluid food substance from a transported receptacle, or wetting the bag with water when it is transported in the rain.

Description of the Invention

In general, the present invention envisages making a new convertible transportable container which is compatible for the transport of food and food substances in general, having a relatively simple and inexpensive structure, but marked by high strength and convenience of use, including for the purpose of its conversion into a placemat or the like. It is therefore a related object of the invention to make such a container the conversion of which between two different configurations of use is simple and quick, and poses no risk of breakage or tearing. A further object of the invention is to make such a container that is significantly stronger than known containers made of paper material, and the strength characteristics of which are not affected by possible contact with food liquids or substances. An auxiliary object of the invention is to make such a container that is easy to carry. Another auxiliary object is to make such a container that, possibly, can be used repeatedly, in both of its possible configurations of use, i.e., has a reversible nature. A further auxiliary object is to make such a container which can be easily and effectively disposed of in an environmentally friendly manner.

At least one of the aforementioned objects is achieved, according to the invention, by a convertible transportable container having the characteristics set forth in the appended claims. A kit comprising such a convertible container also relates to the invention. The claims form an integral part of the technical teaching which is provided herein in connection with the invention.

Brief Description of the Drawings

Further objects, characteristics and advantages of the invention will result from the following description, made with reference to the attached drawings, provided as a non-limiting example only, wherein:

Figure 1 is a schematic perspective view of a convertible transportable container in accordance with possible embodiments of the invention, in a first configuration of use; 3

Figure 2 is a schematic view similar to that in Figure 1, wherein generic receptacles housed in the convertible transportable container are highlighted;

Figure 3 is a schematic perspective view of the convertible transportable container of Figure 1, in a second configuration of use;

Figure 4 is a schematic perspective view similar to that in Figure 1, of a convertible transportable container in accordance with other possible embodiments of the invention; and

Figure 5 is a partial and schematic perspective view of a closure system of a convertible transportable container according to possible embodiments of the invention.

Fmbodiments of the Invention

Reference to one embodiment within this disclosure indicates that a particular configuration, structure, or characteristic described in relation to the embodiment is comprised in at least one embodiment.

Thus, phrases such as “in one embodiment”, “in various embodiments”, and the like, possibly found in different places in this disclosure, do not necessarily refer to the same embodiment. Also, particular conformations, structures, or characteristics defined within this disclosure may be combined in any appropriate manner in one or more embodiments, even different from those shown. The numerical and spatial references (such as “upper”, “lower”, “high”, “low”, etc.) used herein are for convenience only and thus do not define the scope of protection or extent of the embodiments. The same reference numerals are used in the figures to indicate similar or technically equivalent elements. Referring initially to Figure 1, reference numeral 1 globally indicates a convertible transportable container, particularly for transporting food, according to possible embodiments of the invention.

The basic structure of the container 1 comprises a semi-rigid sheet 2 and releasable clamping means, denoted 3 and 4. As explained below, the clamping means 3 and 4 are susceptible to assume an engagement condition, wherein the sheet 2 is maintained in a wrapped configuration (visible, for example, in 4

Figures 1-2), and a release condition (visible, for example, in Figure 3), wherein the sheet 2 can be brought to assume an unwrapped configuration. The sheet 2 preferably has a substantially quadrangular outline, preferably substantially rectangular.

In various preferred embodiments, the container 1 comprises two generally filiform elements intended to serve as shoulder straps, i.e., suitable for allowing the container 1 to be carried as a backpack, as clarified below. The two filiform elements, denoted 5 and 6, may, e.g., be in the form of a rope, a strip, or a ribbon. In the following of the present disclosure, the two elements 5 and 6 will be identified as “ropes”, only for simplicity, and because the use of ropes to make the elements 5 and 6 is currently considered preferable.

In the use of the container 1, i.e., in the assembled condition, the two ropes 5 and 6 are closed-loop: this means that each element 5 and 6 may initially consist of an unknotted rope (or the like), and that, after the assembly that will become clear later, the two opposite ends of the rope may be knotted or otherwise constrained together to form a closed loop.

In various embodiments, the ropes 5 and 6 are constrained in a sliding manner to the sheet 1, at respective points of constraint. In the case exemplified in the figures, the sliding points of constraint for each rope 5 and 6 are made by means of the annular elements 7 and 8 respectively, which are secured in place on the sheet 2, as described below. In the various preferred embodiments, the annular elements 7 and 8 are themselves made of small closed-loop ropes. In the following disclosure, for simplicity sake, the elements 7 and 8 will also be identified as “loops”.

As particularly visible in Figure 3, the sheet 2 extends in a direction of length L and a direction of width W and, due to its semi-rigid nature, is susceptible to being folded at a plurality of folding zones, extending in the width dimension W. Thus, as explained below, the sheet 2 can be brought to assume a wrapped configuration, i.e., partially “rolled” on itself, as in Figures 1-2, and an unwrapped configuration, substantially as in Figure 3. In the wrapped configuration, a plurality of different sheet regions can be identified in the sheet 5

2. In the case shown in Figure 3, for this purpose, lines B are shown corresponding to the aforementioned folding zones, which allow for a more intuitive identification of the aforementioned sheet regions, described below.

The lines B in Figure 3 can be understood as preferred folding lines, one or more of which can be predefined at the production stage in order to facilitate giving the sheet 2 a substantially predetermined outline, when the sheet itself is brought to assume its respective wrapped configuration; however, obtaining the above folding lines at the production stage constitutes only a preferred element of the invention.

In the example shown, a plurality of folding lines or zones B (distinguished from each other by the additional references 1 through 5) are highlighted, all of which are not necessarily defined at the production stage; for example, only the folding line shown as B3 might be defined at the production stage, with the other lines shown as Bl, B2, B4, and B5 being formed (or beginning to form) when the sheet 1 is first brought to assume the wrapped configuration.

As mentioned, the folding lines B identify in the sheet 2 a plurality of different sheet regions, which include two opposite end regions, denoted 2a and 2b, and at least one region 2c-2e that is intermediate to the two end regions 2a and 2b. In the non-limiting example shown, five folding lines B are provided, of which one - denoted Bl in Figure 3 - is provided to divide the end region 2a of the sheet 2 into two sub-regions 2a’ and 2a”. As mentioned above, however, the lines B could also be different in number from the one exemplified, such as e.g. four.

The sheet 2 is susceptible to assume the wrapped configuration shown in Figure 1, that is, a configuration wherein the end region 2a is at least partially overlapping the end region 2b. In the wrapped configuration, as visible in Figure 1, one surface of the sheet - denoted 2’ in Figure 1 - makes the outside of the container 1, while the opposite surface - denoted 2” - makes the inside of the container 1, bounding at least part of a transverse containment space S, susceptible to contain generic objects, such as the receptacles indicated by C in Figure 2. The containment space S is referred to here as “transverse” because, 6 even in the wrapped configuration of the sheet 2, this space is open at the two opposite side ends of the container 1.

In various embodiments, one or more of the sheet regions 2a- 2e are secured to one or more pairs of sliding and guiding elements for the ropes 5 and 6, here represented by the aforementioned annular elements or loops 7 and 8. Referring, for instance, to Figure 3, in the various embodiments in the end region 2a, and particularly in its sub-region 2a’, two loops 7 and 8 are secured in positions substantially aligned with each other in the direction of width W of the sheet 2. Similarly, in at least another sheet region, here the intermediate region denoted 2c, two additional loops 7 and 8 are secured, also in positions substantially aligned with each other in the direction of width W. Preferably, the two loops 7, on one side, and the two loops 8, on the other side, are in positions substantially aligned with each other in the direction of length L of the sheet 2. Preferably, the intermediate region 2c is the one that, in the wrapped configuration of the sheet 2, is in a generally opposite position to the at least partially overlapping end regions 2a and 2b (see, e.g., Figure 1).

The semi-rigid sheet 2 has a substantially wicker-like structure, that is, it is formed by the interweaving of plant fibers, particularly fibers of the biodegradable or compostable type, very particularly plant fibers compatible for food use. In accordance with a feature of the invention, the fibers used to make the sheet 2 are fibers of water hyacinth (or hyacinth living in water, according to another name), which is easily worked for the purpose of obtaining wicker-like structures, as well as being biodegradable and compatible for food use.

Water hyacinth is a plant that - e.g., in tropical areas - grows wild among other things along the edges of rivers. Water hyacinths are thus floating plants with flowers, thick leaves and a stem which is susceptible to being dried. For the purpose of use, after the plants are harvested, the flowers and leaves are cut off and the stems - up to 80 centimeters long on average - are spread out to dry. The stems are preferably hung to avoid the formation of creases that could complicate subsequent working, as well as to prevent crushing of the cellulose pulp they contain. Drying is done naturally, in order to first remove all the water 7 contained in the stems, and then the residual moisture, as well as to avoid damage to the woody tissues and cellulose pulp, which could adversely affect the mechanical characteristics of the stems themselves, in subsequent working stages.

After drying, the stems are pressed, preferably by mechanical press, in order to reduce the overall size of the cellulose pulp. In this way, the air absorbed by the cellulose pulp is substantially removed from the stem, with the latter still remaining present, to improve the mechanical strength characteristics of the dried fiber: this makes it possible to speed up and simplify the subsequent interweaving process, which is preferably done by hand, according to methods known in themselves.

Once a sheet of material of predefined dimensions, preferably substantially rectangular in shape, has been obtained from the interweaving of the fibers, the sheet itself is subjected to a temporary folding operation, e.g. by means of a mechanical press. By means of this operation the sheet itself can be given at least one preferred folding line which, as previously mentioned, can subsequently be the basis or reference for the wrapping of the sheet 2 to form the container 1. Referring to the example in Figure 3, the preformed preferred folding line can be e.g. that indicated by B3, to define the fold which, in the final product represented by the container 1, lies between the “bottom” region 2c and the “back” region 2d of the container itself (see, e.g., Figure 1). Of course, there is nothing to prevent imposing several preferred folding lines on the sheet in advance, however this is not strictly necessary. In fact, the provision of a single preferred folding line is sufficient, as it still allows a reference to be provided to a user, for the purpose of the manual folding of the sheet 2.

Even following the definition of at least one preferred folding line, the sheet 2 can still maintain a substantially planar configuration, in part because of its inherent flexibility. This is advantageous for the purpose of the transportation and storage of the sheets 2.

A substantial advantage of the use of water hyacinth fibers for the purpose of making the sheet 2, which forms the basic structure of the convertible container 8 covered by the present invention, is its suitability for contact with food substances in general, in view of its chemical and physical properties, particularly in view of the fact that such plant fiber does not operate as a suitable substrate for the growth of microorganisms and does not release any volatile, semi-volatile or non-volatile organic matter, or any heavy metal, as clarified below.

In any case, in particularly advantageous embodiments of the invention, the sheet may be provided with a coating of natural origin having antimicrobial properties towards the sheet itself and not towards the products that are placed in contact therewith, preferably at least on its inner side 2”, as follows: such a coating may, e.g., be applied by spraying or brushing.

In the preferred embodiments, the ropes 5 and 6 can also be obtained by interweaving plant fibers, particularly biodegradable and/or compatible for food use. In this vein, the ropes 5 and 6 can also be obtained by means of water hyacinth fibers, according to a technique known in itself. The same applies to the constraint loops 7 and 8 of the ropes 5 and 6.

In various preferred embodiments, a handle 9 or the like protrudes from the outer side 2’ of the end region 2a, preferably but not necessarily in a position substantially intermediate to the loops 7 and 8 which are associated with that sheet region 2a, particularly its sub-region 2a”. The handle 9 may also consist of one or more generally filiform elements, such as e.g. in the form of a string or a strip or a ribbon. The element or elements making such a handle 9 may also be made from plant fibers, particularly biodegradable and/or compatible for food use, preferably also made from water hyacinth. The handle 6 may be formed by two closed-loop lanyards passing through relevant slits that exist between the interwoven fibers of the sheet 2, the ends of which are knotted at the inner side of the sheet itself; of course, it is also possible to provide a single lanyard, wrapped so as to form two closed loops, with the relevant ends knotted, or a single lanyard to form a single closed loop.

As mentioned above, releasable clamping means are also associated with the sheet 2, suitable for maintaining the sheet itself in its respective wrapped 9 condition, i.e., in the configuration of Figure 1 or 2. In the case exemplified in Figures 1-2, and as visible in the detail of Figure 5, on the outer side 2’ of the end region 2a (in the example, the outer side of its end sub-region 2a’) a first engagement element is secured, e.g. in the form of a disc 3. The disc 3 can, e.g., be secured in place by means of a respective lanyard 3 a, to make a kind of seam; such a lanyard 3a can also, e.g., be constrained by taking advantage of one or more slits that exist between the interwoven fibers of the sheet 2. The lanyard 3a can also be formed from biodegradable or compostable material, such as e.g. the woven textile fibers of water hyacinth. The disc 3 can be formed from biodegradable or compostable material, and compatible for food use, e.g., wood or compacted water hyacinth fibers.

In the wrapped configuration of the sheet 2, the region 2a (i.e., its aforementioned end sub-region 2a’) is overlapped on a portion of a further intermediate region of the sheet 2, here a region 2d that is intermediate to the regions 2b and 2c (i.e., a “front” region of the container 1), and from the outer side of such further intermediate region 2d protrudes at least a second substantially filiform engagement element, e.g., two portions of a lanyard 4, that are engageable and disengageable with respect to the disc 3. The lanyard 4 may also be formed from biodegradable or compostable material that is particularly compatible for food use, e.g., woven textile fibers of water hyacinth. The end portions of the lanyard 4 can, e.g., be rolled several times around the seam given by the lanyard 3 a that secures the disc 3 in place, below it, to constrain the regions 2a and 2d together; when it is necessary to separate these regions from each other, however, for the purpose of switching to the unwrapped configuration of the sheet 2, it will be sufficient to unroll the end portions of the lanyard 4 from the aforementioned seam. Of course, it is also possible to arrange the lanyard 4 so that it forms - at the outer side 2’ of the region 2d of the sheet 2 - an annular handle, which can be engaged with respect to the disc 3 and to the relevant seam 3a. Of course, from the region 2d of the sheet two separate lanyards 4 could also protrude to be constrained with respect to the seam 3 a or to the disc 3, or again the first and the second engagement elements could both 10 be in the form of lanyards, which can be tied and untied with each other, as needed. It is, however, obvious to the experienced person that the means 3-4 to constrain the regions 2a and 2d of the sheet 2 together in a releasable manner may be of a different type from that exemplified.

For assembly purposes, starting with the interwoven sheet 2, the loops 7 and 8 are constrained to the corresponding points on the sheet itself, also e.g. by exploiting existing spaces between the interwoven fibers (the loops 7, 8 can also be lanyards tied at the ends to form closed loops). The sheet 2 is then also associated with the handle or grip 9 and the clamping means 3-3a and 4, as indicated above. The ropes 5 and 6 are then fitted through, with the possibility of sliding, into the corresponding loops 7 and 8, respectively. After fitting through the loops, the two ends of each rope 5 and 6 can be tied together, such as knotted, to form the corresponding closed loop.

For the purpose of use for food transport, the sheet 2 can be wrapped around itself in order to define the space S in Figure 1 to receive the relevant contents. For example, referring to the case shown in Figures 2-3, a user will place the three receptacles C stacked on the bottom region 2c (i.e., to the right of line B3 in Figure 3); thereafter, and again referring to Figure 3, the right side of the sheet - corresponding to the regions 2d and 2b will be folded over the stack of receptacles C, up to the top of the topmost receptacle C in the stack; the left side of the sheet - corresponding to the regions 2e and 2a - will then be folded partially over the stack of receptacles C and partially over the regions 2b and 2d. At this point, the means 3-3a and 4 will be engaged with each other to keep the sheet 2 in the wrapped condition.

The two ropes 5 and 6 are of such a length that, in the wrapped configuration of the sheet 2, and as seen e.g. in Figures 1 and 2, the container 1 is transportable as a backpack, with the two ropes 5 and 6 serving as shoulder straps. In various preferred embodiments, the location of the means of constraint and sliding guides for ropes 5 and 6 - here represented by the loops 7 and 8 - is chosen so that, in the wrapped configuration of the sheet 2, a section of each rope 5 and 6 extends to one side of the transverse containment space S, as shown in Figure 1 11

(where such a section of rope is denoted by 5x). Thus, as can be seen from Figure 2, such sections of rope can advantageously serve as lateral containment elements for the object(s) C housed in the containment space S.

Thanks to the length of the ropes 5, 6 and their ability to slide in the relevant loop elements 7, 8, the sheet 2 can be brought to assume the unwrapped configuration, wherein the sheet 2 is at least approximately planar, to serve, e.g., as a mat or as a placemat, on which, for example, to consume a food item previously carried by means of the container 1. The concept can be understood from Figure 3, wherein the sheet 2 is substantially shown at an intermediate stage in its switch from the wrapped configuration to the unwrapped configuration. As mentioned, this switch between the two configurations is made possible by the sliding of the ropes 5, 6 with respect to the relevant loops 7 and 8, and by the substantially flexible structure of the sheet 2.

Given the semi-rigid nature of the sheet 2, the sheet itself will tend slightly (due to its elastic memory) to revert towards the wrapped configuration: however, by simply placing objects on the unwrapped sheet ensures that it is sufficiently planar (moreover, the problem practically does not arise by flipping the sheet 2 with respect to the condition shown in Figure 3).

As can be guessed, the clamping means represented by components 3-3a and 4 ensure that the wrapped configuration is maintained for the use of the container 1 for transport purposes. Thereafter, by releasing those means 3-3a and 4, and simply stretching out the sheet 2 as explained above, by virtue of the ability of the ropes 5 and 6 to slide, the container 1 can be brought to the unwrapped configuration, wherein it serves as a mat or placemat, or the like. If necessary, in order to return to the wrapped configuration, simply return the sheet towards its initial condition.

The provision of the loops 7 and 8 is a preferred feature of the container 1, but not an essential one. In fact, in possible variants of embodiment, the function of constraining and guiding the ropes 5 and 6 to slide could be achieved by exploiting relevant spaces or slits 7’, 8’ between the interwoven fibers of the sheet, as exemplified in Figure 4. In such a case, in the unwrapped condition, a 12 respective section of the two ropes 5 and 6 will be extended at the inner side 2” of the sheet 2, while the remaining part of the same ropes 5 and 6 will be at the outer side 2’ of the sheet 2.

The container 1 in accordance with the invention may be part of a set or kit comprising one or more box receptacles, prepared, in terms of size, to be housed in the containment space S. Figure 2 precisely exemplifies the case of three box receptacles C, formed from material suitable for food use. In the example, each receptacle C has a box base Cl or tray, with which a lid C2 is associated in a removable manner, the two parts Cl and C2 defining between them a containment volume for food. Advantageously, the container C or its parts Cl and C2, can be formed from a biodegradable and/or compostable material. The container C or each container C in the set will preferably be sized so as to be housed in an area comprised between the sections of the ropes 5 and 6 that extend to the sides of the space S, as shown in Figure 2 (in which only one section 5x is visible), where the aforementioned sections serve as lateral containment elements for the stack of receptacles C (Figure 4 shows the two sections 5x and 6x for the two ropes 5 and 6).

The convertible transportable container covered by the present invention is particularly suitable for food transportation in view of the chemical and physical properties of its constituent material, namely water hyacinth.

The water hyacinth used in the manufacture of the sheet 2, that is, its woven fibers, is not subjected to any treatment with artificial chemicals but only to the aforementioned drying process, and thus without the use of solvents, or adhesives, or binders, or paints, or the like. Water hyacinth as such, in contrast to other plant fibers (such as bamboo, for example), is an substantially inert material in that it does not have colonies of microorganisms on its surface and does not release any organic substances or heavy metals, i.e., it does not contaminate foods placed in contact therewith. Therefore, water hyacinth meets the requirements set forth in Regulation (EC) 1935/2004, which establishes that the materials or objects intended to come into contact, directly or indirectly, with food must be sufficiently inert to exclude the transfer of substances to food 13 in quantities that could endanger human health or result in an unacceptable change in the composition of food or a deterioration of its organoleptic characteristics.

As just mentioned, the water hyacinth has no colonies of microorganisms on its surface and exhibits a more than acceptable microbiological level. In fact, microbiological analyses have been conducted on the water hyacinth and no molds and yeasts, aerobic mesophilic microbial load, coliforms, enterobacteria, coagulase-positive staphylococci, strains of salmonella or Pseudomonas aeruginosa were detected on its surface. This implies that water hyacinth - which, let us recall, has not been subjected to any chemical treatment of any kind and, in particular, to sanitization/hygienization treatments - is a plant fiber that does not allow the growth of microorganisms on its respective surface, that is, it possesses chemical and physical characteristics that allow it to be placed in direct contact with food by not acting as a carrier of microorganisms harmful to human health. The convertible transportable container for food covered by the present invention can thus be used without danger to consumers, since even unpackaged food that may be placed directly on its respective surface will not be contaminated by any microorganisms.

The possible antimicrobial effect of the water hyacinth was also checked, which - if present - would affect the use as a material for making food containers since it could not be considered an inert material as defined by the Regulation (EC) 1935/2004.

The determination of the antimicrobial effect was carried out using the official EN 1104 method (MI 1104 rev.Ol 2020), which involves the preparation of cultures of various types of living organisms subsequently placed in contact with the test sample.

Specifically, the antimicrobial effect of water hyacinth was evaluated by observing the generation of areas of growth inhibition within cell cultures of Bacillus substilis and Aspergillus niger when placed in contact with water hyacinth by observing the behavior of cell cultures near and at the water hyacinth. 14

Analyses did not show antimicrobial properties of water hyacinth, such that this plant fiber is microbiologically inert and adapted to be placed directly in contact with food, despite having the ability to prevent the formation of colonies of microorganisms on its surface, as indicated above.

Specific experimental analyses designed to verify the release from the water hyacinth of non-intentionally added substances (so-called NIAS - Non Intentionally Added Substances ) have also been conducted, where this expression refers to substances derived from degradation processes, impurities, reaction products or other contaminants directly derived from the water hyacinth that, if released into the food, could migrate therein, by polluting it and thus making it no longer suitable for consumption.

In particular, analyses have been carried out which are intended to determine:

(i) any volatile and semi-volatile organic compounds released from the plant fiber of water hyacinth as is through gas chromatographic analysis with mass detection by headspace solid-phase micro-extraction (SPME-HS- GC/MS) and

(ii) any semi-volatile and non-volatile organic compounds on the extraction liquid of the water hyacinth plant fiber side intended for food contact through gas chromatographic analysis with mass detection (GC/MS).

The analyses carried out did not reveal the release of any volatile, semi-volatile and non-volatile organic matter by the plant fiber involved.

The identification of organic matters is done by comparison with libraries contained in the analytical instrument by comparing the ion profile of the fragmentation of the substance found with the profiles of the molecules in the instrument’s libraries. Semi-quantification of organic matters is performed using the response factor of the internal standard assuming that they have the same response factor as the standard; the use of the internal standard allows organic compounds attributable to the environmental contamination or to the solvents/reagents and glassware used to be excluded from attribution to the sample. 15

The aforementioned analyses were carried out according to the specifications given below:

(i) VOLATILE AND SEMI- VOLATILE ORGANIC COMPOUNDS

INSTRUMENT

Gas chromatograph Shimadzu

Mass spectrometer Shimadzu

Chromatographic column HP-5ms

Extraction mode SPME-HS

OPERATING CONDITIONS

Mass acquisition range m/z 35÷400

Internal standard 1 ,4- bromofluorobenzene

PERFORMANCES

Sensitivity 0.2 pg/dm ²

COMPOUND RECOGNITION

Library ST/EPA/NIHMass

Spectral Library

RECOGNITION CRITERIA

Match Quality > 90 Good

Match Quality between 80-90 Acceptable Match Quality < 80 Unidentified The analysis did not detect the presence of volatile and semi-volatile organic compounds in concentrations above 0.2 pg/dm ² (such as 1.4- bromofluorobenzene) .

(ii) SEMI-VOLATILE AND NON-VOLATILE ORGANIC

COMPOUNDS INSTRUMENT

Gas chromatograph Agilent

Mass spectrometer Agilent

Chromatographic column HP-5ms

OPERATING CONDITIONS

Mass acquisition range m/z 50÷1000

Internal standard 1 (quant.) 4.4-difluorbiphenyl

Internal Standard 2 (LoQ) Metilmargarate 16

EXTRACTION CONDITIONS

Extraction solvent MPPO (Modified

Polyphenyl Oxide)

Contact mode Immersion

Contact surface 1 dm2

Contact volume 50 mL

MPPO weight 4 g

Contact time and temperature 10 days at 40 °C

PERFORMANCES

Sensitivity 0.010 mg/kg food

COMPOUND RECOGNITION

Library NIST/EPA/NIH Mass

Spectral Library

RECOGNITION CRITERIA

Match Quality > 90 Good

Match Quality between 80-90 Acceptable

Match Quality < 80 Unidentified

The analysis did not detect the presence of semi-volatile and non-volatile substances in concentrations above 10 pg/kg (such as 4.4-difluorbiphenyl).

In a particularly preferred embodiment, the convertible transportable container covered by the present invention has on at least one respective surface, preferably a surface intended to be in contact with food, a coating having antimicrobial characteristics, particularly based on aqueous sumac extract. The container so coated - i.e., the sheet 2 so coated at least on its inner side 2” - is suitable for being placed in contact with food or tools used for the consumption of food (e.g., cutlery), since the water hyacinth dried and treated with such extract does not interact by “sanitization” with the food placed in direct contact therewith, but is such as to preserve its safety and hygiene over time.

The aqueous sumac extract - although provided with its own antimicrobial effect (which will be discussed shortly) - when applied to the dried water hyacinth no longer exerts any antimicrobial activity but behaves as a surface 17 antimicrobial with respect to the water hyacinth alone, precisely ensuring its respective safety and hygiene and consequently its suitability for use as a material for making food containers. As we have seen, the production process of the water hyacinth fibers used to make the transportable convertible container described herein involves subjecting this plant fiber to drying and subsequent pressing. This implies that the cellulose and lignin that constitute the plant fiber undergo neither chemical nor physical alteration. Without wishing to bind oneself to any theory in this regard, it is believed that the cellulose pulp retained in the plant fiber acts as an absorbent material of sumac extract and also prevents the release of that extract by the fiber itself, such that the treated water hyacinth fiber exhibits characteristics suitable for the production of food containers, which will meet the requirements set forth in Regulation (EC) 1935/2004 by being substantially inert with respect to the food with which they come into contact.

In an embodiment, the aqueous sumac extract is made by infusing sumac berries in boiling water. Specifically, this aqueous extract is obtained by infusing sumac berries with exocarp and seed (about 500 ml) in boiling water (about 500 g); once the solution reaches room temperature (allowing it to settle and decant), the respective filtration and subsequent bottling are carried out. The solution is stored at about 4 °C, in a refrigerator. During the infusion stage, water-soluble tannins contained in sumac berries - which are responsible for the antimicrobial activity of the extract - are extracted from the berries.

In one embodiment, during the production stage the aqueous sumac extract is applied to the container in liquid or spray form on at least one respective surface, preferably on the surface intended to be in contact with food. In addition or alternatively, one application of the aforementioned extract may take place later, such as at the time of using the container 1.

The aqueous sumac extract was characterized by HPLC/Q-TOF (high- performance liquid chromatography-quadrupole time-of-flight mass spectrometry) in order to verify the presence of pollutants of various kinds in this extract at very low concentrations. Characterization was performed with 18

Shimadzu Nexera X2 UHPLC instrumentation coupled with a high-resolution QTOF Sciex 4600 mass spectrometer. This technique performs an initial chromatographic-level separation of the analytes using the ultra-high performance liquid chromatography (UHPLC) system. Next, the analytes are desorbed by the Electron Spray Ionization (ESI) source and enter the QTOF system, where they are further separated by the first quadrupole based on their mass-to-charge ratio and finally by the time-of-flight analyzer, which allows for high resolution of the molecular ions enabling brute formula identification. With this technique, all ions in both positive and negative modes with a mass-to- charge ratio between 50 and 1200 Da are acquired.

The sample was analyzed following 1:20 dilution with distilled water. A solvent blank was analyzed in parallel.

The compounds identified in the aqueous sumac extract are shown qualitatively and quantitatively in Table 1. No pollutants were identified within this extract. The compounds mainly present in the aqueous sumac extract are: gallic acid (about 26 percent), oxydisuccinic acid (about 8 percent), petunidin-3-O- glucoside pyruvate (about 9 percent) and mycyrin-3-O-deoxyhexoside (about 9 percent).

19

Table 1.

The aqueous sumac extract was also subjected to analysis by the official EN 1104 method mentioned above to check for any antimicrobial effect. The results of this analysis demonstrated antimicrobial activity of the extract against 20

Bacillus substilis : indeed, areas of inhibition of the growth of this bacterium are evident near and at the inoculation of the extract on the Petri dishes on which the bacterium was grown under suitable conditions.

In order to verify whether water hyacinth treated with the aqueous sumac extract is suitable to be placed in contact with food, additional experimental tests were carried out that evaluated:

(i) the antimicrobial properties,

(ii) a possible release of the polyphenols contained in sumac extract into dry food and

(iii) the migration of heavy metals.

All tests (which will be reported below) were negative: the dried water hyacinth treated with the aqueous sumac extract is an inert material suitable for being placed in contact with food as no antimicrobial activity and no release of substances was detected.

As for the antimicrobial activity of water hyacinth treated with aqueous sumac extract, this was evaluated according to the method EN 1104 (as described above). Again, no growth inhibition activity of Bacillus substilis and Aspergillus niger was detected.

Evaluation of the release of polyphenolic compounds by water hyacinth treated with aqueous sumac extract when in contact with a dry food simulant was carried out by applying:

(i) the HPLC/Q-TOF technique, as described above, to identify non-volatile and high-boiling polar substances, and

(ii) gas chromatography coupled with mass spectrometry (GC/MS) to identify non-volatile apolar substances.

The dry food simulant used is modified polyphenyl oxide (also known as MPPO or TEN AX).

As for GC/MS analysis, this was carried out with Shimadzu QP2010SE GC MS instrumentation. This analysis compares the quantities of analytes determined with an internal standard by operating a semi-quantitative evaluation. Qualitative recognition of analytes is operated by means of NIST library 21 supplied with the instrument; the comparison between the revealed mass spectra and those in the library is expressed as percent probability of matching. An amount of analyte in the dry food simulant equal to 90 ug/kg is identified as LOI ( level of interest)·, analyte recognition is positive when the percent probability of matching is greater than 80% by comparison with the NIST library.

Water hyacinth treated with aqueous sumac extract was placed in contact with TENAX for about 2 hours at a temperature of about 70 °C.

Both analyses showed that the treated water hyacinth did not release substances into TENAX beyond the legal limits. Specifically, HPLC/Q-TOF analysis did not find any compounds related to polyphenols characterizing the aqueous sumac extract as per Table 1 above; GC/MS analysis did not find the presence in TENAX of either substances contained in the aqueous sumac extract or other intentionally added substances and potentially harmful to health.

In relation to the migration of heavy metals by water hyacinth treated with aqueous sumac extract, this was evaluated using the UNI EN 71-3:2019 method. The heavy metals evaluated were aluminum, antimony, arsenic, barium, cadmium, cobalt, chromium, manganese, mercury, nickel, lead, copper, tin, strontium, zinc, boron and selenium. The results of the analysis showed that these heavy metals are not released from the treated water hyacinth, which therefore meets the requirements set by Regulation (EC) 1935/2004.

In one embodiment, the container treated with sumac extract in accordance with the invention may be part of a set or kit comprising a vial containing the aqueous sumac extract as described above, for further application, preferably at the time of use, to a surface of the container, preferably the surface intended to be placed in contact with food. The extract can again be applied by spraying or brushing. In this way, the container can be further sanitized before unpackaged food is placed thereon.

In conclusion, water hyacinth treated with aqueous sumac extract constitutes a suitable material to be placed in contact with at least dry food at room 22 temperature or by placing hot food thereon for a period of time up to 2 hours and with repeated use.

From the description made, the characteristics of the present invention are clear, as are its advantages.

The convertible container described is of simple and economical construction, has a low weight and a particularly sturdy structure, substantially immune to the risk of tearing during conversion between two of its possible configurations, or during use for transportation purposes. The container also proves to be particularly resistant following possible contact with water or other liquids, as it is able to absorb them without deteriorating, thanks to the presence of its pulp, which, in a way, acts as an anhydrous sponge. The presence of the pulp, albeit in a dried condition, allows for a “cushioning effect” with respect to the receptacles housed in the container.

The construction of the sheet structure using water hyacinth fibers makes the container easily disposable, when necessary, as it is completely or nearly completely biodegradable or compostable. Moreover, the container itself need not be intended as a disposable item, in view of its reversible structure (wrapped to unwrapped and unwrapped to wrapped).

Due to the chemical and physical characteristics of water hyacinth, the container can be used for the transportation of food, in view of its ability not to act as a substrate for the growth of microorganisms and not to release any substances, with obvious advantages in, e.g., the street food, take-away catering, ready-to- go catering, and horeca sectors in general. The preferred presence of the relevant coating further ensures the suitability of the container for use in conjunction with food substances, as it has been shown that water hyacinth treated with the aforementioned coating does not release any substance contained in the coating.

Another advantage of the invention lies in the possibility of carrying the container directly as a backpack, which has obvious practical advantages: carrying the container does not involve the engagement of one or both hands, 23 which is convenient for those involved (think of the customer of a fast-food restaurant, or a take-out food establishment, or a stall).

It is clear that numerous variations are possible for the person skilled in the art to the transportable convertible container and kit described as an example, without departing from the scope of the invention as defined by the following claims.

It will be appreciated that the region indicated by 2b in the figures could possibly be omitted, in which case the function of the second end portion of the sheet 2, i.e., the portion opposite the region 2a, will be made by the portion indicated by 2d.