EP4683867A1

EP4683867A1 - Compostable top lid structure for a beverage preparation capsule

Info

Publication number: EP4683867A1
Application number: EP24710766.7A
Authority: EP
Inventors: Chiara PAVAN; Federica SORDO
Original assignee: Societe des Produits Nestle SA; Nestle SA
Current assignee: Societe des Produits Nestle SA; Nestle SA
Priority date: 2023-03-20
Filing date: 2024-03-15
Publication date: 2026-01-28
Also published as: WO2024194163A1; AU2024239231A1; MX2025011116A; CN120835858A

Abstract

The invention relates to a capsule (100) for preparing a beverage in a beverage production machine, the capsule (100) comprising a capsule body (200) delimiting a chamber (250) for containing a beverage substance (500), an injection wall (220) closing the chamber at a first end and a delivery wall (300) closing the chamber (250) at a second end of the capsule body (200). The delivery wall (300) comprises in a layered manner a carrier layer (320) for carrying the subsequent layers, an optional filter layer (310) and a barrier layer (340) applied on the carrier layer (320), the barrier layer (310) providing a preferably bidirectional barrier against moisture and/or gas, the barrier layer (340). As proposed the barrier layer (340) is applied in one or more layers in a total quantity of 0,5 to 10 gsm (g/m2), preferably of 1,5 to 4 gsm (g/m2) and is applied on least one of the carrier layer's surfaces, said surface having a surface roughness lower than 1;3 microns when measured according to ISO 3274. The invention also relates to a system comprising the proposed capsule and to a use of the proposed capsule for preparing a beverage in a beverage production machine

Description

COMPOSTABLE TOP LID STRUCTURE

FOR A BEVERAGE PREPARATION CAPSULE

Field of the Invention

The present invention relates to a capsule for preparing a beverage in a beverage production machine, to a system comprising the proposed capsule and to a use of the proposed capsule for preparing a beverage in a beverage production machine.

Background

Single-serve beverage capsules for beverage preparation machines are known in the art. These capsules are commonly used for on demand dispensing of beverages, like coffee, tea or hot chocolate, and enjoy popularity due to their fresh tasting, variability of flavors and the convenience of the beverage preparation.

Usually, the capsule containing a beverage component is inserted in a capsule holder of a beverage preparation machine, the capsule holder is closed, and the beverage preparation is started. Fluid, such as water or milk, is delivered to the capsule to interact with the beverage component contained inside the capsule to produce the desired beverage. When a sufficient amount of the fluid fills the capsule, the capsule opens under pressure of the fluid to release the prepared beverage. For example, opening of the capsule can be accomplished by pressing an extraction face of the capsule with a force effected by increasing pressure of the fluid inside the capsule against an opening structure provided in the capsule holder such that the extraction face is torn upon reaching a breaking stress thereof. The opening structure can be a number of relief and recessed elements, e.g., pyramid-like elements, onto which the extraction face extends and tears under the effect of the internal pressure of the fluid. Such pressure-controlled beverage preparation has the advantage that it can produce a beverage of high quality.

However, a high number of parameters and dynamic effects can influence the opening process of the capsule on the extraction face with the aforementioned opening structure and thus, repeatability and consistency in the opening process are difficult to achieve, which may have a negative impact on the result of the finished beverage. In particular, it has been found that the extraction face needs to show a certain amount of stiffness to ensure pressure built-up in the capsule while avoiding collapse thereof during the opening process. Conversely, the extraction face should be configured such that it can be torn by the opening structure in the opening process. Also, it is desirable that particles and fibers from the beverage component are retained inside the capsule to avoid not only contamination of the prepared beverage but also obstruction of openings in the capsule and/or the opening structure that are provided for dispensing the prepared beverage out of the beverage preparation machine.

In the prior art, these technical challenges are addressed, by forming the extraction face of a membrane made of aluminium with a very precisely controlled thickness, in particular, of about 30 to 40 micrometers. Aluminium offers a number of advantages, such as a high-pressure resistance, durability, flexibility, low weight, provision of long shelf-life and letting the taste of the prepared beverage unaltered. In addition to Aluminium capsules, some consumers are expecting capsules made of alternative material, and in particular capsules made of compostable material.

Therefore, recently various attempts were made to replace Aluminum material used in capsules with alternative materials. For example, bioplastics made from cornstarch or dried pulp made from sugarcane fiber were proposed to be used as capsule materials. However, a disadvantage of such materials is that they do not have the same material properties as presently used materials, like aluminium. For example, capsules made from alternative materials often have a limited shelf-life as they do not provide the same reliable oxygen and moisture barrier as aluminium.

In particular, the design of an extraction face with alternative materials appears to be challenging, as it is not possible to simply transfer the design principles and solutions applied for the former aluminium extraction face to these new materials. Approaches that, for example, simply replace the known aluminium formed extraction face with a paper-based material have proved unsuccessful, because the quality of the prepared beverages, reproducibility of flavors and beverage consistency were not comparable with the high standards set by the known aluminium-based extraction faces.

Additionally, even if some attempts in providing alternative compostable capsules are starting to be successful, the structure and the design of the capsule top lid membrane is still a challenge as the capsule membrane needs to fulfil multiple requirements. Indeed, the capsule top lid membrane should: integrate biodegradable and/or compostable materials, have optimum barrier properties for an improved shelf life of the capsule be tight sealed to the capsule rim, have a structure and related materials allowing the capsule to be opened by the opening structure of the beverage preparation machine during the capsule opening process, provide optimized extraction.

Therefore, it is an object of the present invention to provide a capsule with a configuration and design that facilitates the use of compostable materials for the entire capsule while maintaining and/or exceeding the quality and continuity standards of the capsule itself and of the prepared beverage as set by a comparable aluminium capsule, especially with an improved top lid membrane as a delivery wall for the beverage to be delivered during extraction.

These and other objects, which become apparent upon reading the description, are solved by the subject-matter of the independent claims. The dependent claims refer to preferred embodiments of the invention.

Summary of the Invention

As used herein, the term "machine" or "device" may refer to an electrically operated device or machine that: can prepare, from a precursor material or ingredient, a beverage and/or foodstuff, or; can prepare, from a pre-precursor material, a precursor material that can be subsequently prepared into a beverage and/or foodstuff. The machine may implement said preparation by one or more of the following processes: dilution; heating; pressurization; cooling; mixing; whisking; dissolution; soaking; steeping; extraction; conditioning; infusion; grinding, and other like process. The machine may be dimensioned for use on a work top, e.g. it may be less than 70 cm in length, width and height. As used herein, the term "prepare" in respect of a beverage and/or foodstuff may refer to the preparation of at least part of the beverage and/or foodstuff (e.g. a beverage is prepared by said machine in its entirety or part prepared to which the end-user may manually add extra fluid prior to consumption, including milk and/or water). As a preference in the present invention, the beverage extraction device is a Nespresso Original Line extraction machine as described for example in one or more of EP0512468A1, EP0512470A1, EP1654966A1 or EP2142054A1. The Nespresso® Original Line system when used with capsule made of aluminium, are disclosed along with their opening system, for example, in one or more of EP0512468A1, EP0512470A1, EP1646305A1 or EP1165398A1. In these references, constructional, manufacturing and/or (beverage) extraction details of such aluminium capsules and/or closing members are also disclosed.

In such system, the capsule is intended to be inserted into an extraction device, in which it can be pierced and injected with a fluid that passes through the bed of coffee contained in the capsule. The capsule is then opened against a supporting part of the device comprising raised elements (in the form of truncated pyramids) under the effect of the pressure of the fluid entering and rising in the capsule.

As used herein, the term "container" or "capsule" may refer to any configuration to contain the precursor material, e.g. as a single-serving, pre-portioned amount. The container may have a maximum capacity such that it can only contain a single serving of precursor material. The container may be single use, e.g. it is physically altered after a preparation process, which can include one or more of: perforation to supply fluid; for example a liquid like water, to the precursor material; perforation to supply the beverage/foodstuff from the container; opening by a user to extract the precursor material. The container may be configured for operation with a container processing unit of the machine, e.g. it may include a flange for alignment and directing the container through or arrangement on said unit. The container may include a rupturing portion, which is arranged to rupture when subject to a particular pressure to deliver the beverage/foodstuff. The container may have a membrane for closing the container. The container may have various forms, including one or more of: frustoconical; cylindrical; disk; hemispherical, and other like form. The container may be formed from various materials, such as metal or plastic or wood pulp based a combination thereof. As a preference in the present invention, the container is a compostable capsule, preferably made of cellulose and preferably made as a cellulose or wood pulp molded capsule. The material may be selected such that it is: food-safe; it can withstand the pressure and/or temperature of a preparation process. The container may be defined as a capsule, wherein a capsule may have an internal volume of 20 - 100 ml. The capsule includes a coffee capsule, e.g. a Nespresso® capsule (including a Classic/Original Line, Professional, or other capsule).

As used herein, the term "system" or "beverage or foodstuff preparation system" may refer to the combination of any two or more of: the beverage or foodstuff preparation machine; the container; the server system, and the peripheral device. As used herein, the term "beverage" may refer to any substance capable of being processed to a potable substance, which may be chilled or hot. The beverage may be one or more of: a solid; a liquid; a gel; a paste. The beverage may include one or a combination of: tea; coffee; hot chocolate; milk; cordial; vitamin composition; herbal tea/infusion; infused/flavoured water, and other substance. As used herein, the term "foodstuff" may refer to any substance capable of being processed to a nutriment for eating, which may be chilled or hot. The foodstuff may be one or more of: a solid; a liquid; a gel; a paste. The foodstuff may include yoghurt; mousse; parfait; soup; ice cream; sorbet; custard; smoothies; other substance. It will be appreciated that there is a degree of overlap between the definitions of a beverage and foodstuff, e.g. a beverage can also be a foodstuff and thus a machine that is said to prepare a beverage or foodstuff does not preclude the preparation of both. As a preference, the beverage is coffee including roast and ground coffee.

As used herein, the term "precursor material" or "ingredient" may refer to any material capable of being processed to form part or all of the beverage or foodstuff. The precursor material can be one or more of a: powder; crystalline; liquid; gel; solid, and other. Examples of a beverage forming precursor material include ground coffee; milk powder; tea leaves; coco powder; vitamin composition; herbs, e.g. for forming a herbal/infusion tea; a flavouring, and; other like material. Examples of a foodstuff forming precursor material include dried vegetables or stock as anhydrous soup powder; powdered milk; flour-based powders including custard; powdered yoghurt or ice-cream, and; other like material. A precursor material may also refer to any pre-precursor material capable of being processed to a precursor material as defined above, i.e. any precursor material that can subsequently be processed to a beverage and/or foodstuff. In an example, the pre-precursor material includes coffee beans which can be ground and/or heated (e.g. roasted) to the precursor material. As a preference, within the disclosed extraction process, the precursor material is roast and ground coffee.

As used herein, the term "fluid" (in respect of fluid supplied by a fluid conditioning system) may include one or more of a liquid, for example, water; milk; other.

As used herein the term "wood pulp-based" may refer to the material or a portion of material forming the container which is one or more of: porous; fibrous; cellulosic; formed of cellulosic material; formed of natural cellulosic material; formed of reconstituted or regenerated cellulosic material; non-woven; is composed entirely of or is a composition of wood pulp, and is wet formed. A thickness of the wood-based material may be 0.25 mm to 0.75 mm or about 0.5 mm. The wood-based material may be 200-400 gsm. As used herein the term "non-woven" may refer to a fabric-like material which is not woven or knitted. A non-woven material may be made from bonded together fibres. As used herein the term "porous" may refer to material configured with interstices to transmit water (or other liquid) therethrough. As used herein the term "fibrous" may refer to material comprised of fibres, which may be present in one or more of the material constituents. As used herein the term "cellulosic" or "cellulosic material" may refer to conventionally woody and/or non-woody materials, e. g. manila hemp, sisal, jute, bleached and unbleached soft wood and hard wood species. A cellulosic material may include a regenerated or reconstituted cellulose. As used herein the term "natural cellulosic material" may refer to conventionally woody materials, which are not regenerated. As used herein the term "reconstituted or regenerated cellulosic material" may refer natural cellulosic material subject to processing that comprises reconstitution or regeneration, examples include rayon and lyocell. As used herein the term "wood pulp" may refer to a lignocellulosic fibrous material, which may be prepared by mechanical or chemical separation of cellulose fibres from one or more of wood, fibre crops, paper or rags. As used herein the term "wet formed" may refer to a process of forming from an aqueous solution of fibres. The aqueous solution of fibres may be heated and pressed in a mould to set the material and remove water therefrom.

The capsule of the invention has the same design as a Nespresso® Original Line capsules and is fully made (capsule body and delivery wall) of compostable material, preferably of cellulose-based material, more preferably of pulp-molded cellulose-based material. The capsule is in the form of a frustoconical cup and has for example a diameter of 2 - 5 cm and an axial length of 2 - 4 cm.

In variant embodiments, which are not illustrated: the capsule may have other crosssection shapes, including square, other polygons, or elliptical; the closing member may be rigid or other non-membrane formation; the flange is alternatively connected to the upper surface of the closing member, e.g. by crimping; the sidewall is alternatively arranged, including with the reverse taper or is aligned to the depth direction, or is curved; the base is alternatively arranged, including with as flat or curved; the flange portion is connected to the storage portion rather than being integrally formed; the closing member is arranged as a storage portion, e.g. it comprises a cavity, and; the flange portion is omitted, e.g. the closing member connects directly to the storage portion. A first aspect of the invention relates to a capsule for preparing a beverage in a beverage production machine. In these respects, the invention provides a capsule according to Claim 1.

In more details, the capsule may be understood as a receptacle for containing a substance for preparing a beverage and preferably may form a case or container that surrounds the substance.

The capsule body is of a three-dimension shape. It delimits with its sidewall (at least part of) a chamber, which may be a compartment, a cavity or a hollow space in the capsule, for example. The chamber generally contains a beverage or foodstuff ingredient or substance for the preparation of the beverage. The capsule body also comprises a rim portion delimiting an opening in the sidewall. The capsule further comprises an injection wall suitable for injecting a fluid in the chamber. Injection of the fluid may lead to an interaction of the fluid with the substance, which may include any kind of chemical and/or physical reaction between the substance and the fluid, such as wetting, infusion, extraction, dissolution, and/or any other kind of corresponding interaction to produce a beverage product. The capsule further comprises a delivery wall that is connected to the capsule body to close the chamber. For example, it may be conceivable that a space inside the capsule may be (completely) surrounded from all sides by the container body (sidewall), the injection wall and the delivery wall, preferably such that the chamber for receiving the substance is formed (and closed). Thereby, a capsule can be provided that can be filled with a substance for preparing a beverage and used with known capsule machines. The substance can be protected from degradation and outside influences, like oxidation or moisture, and flavours of the substance can be kept inside the capsule even when storing the same for extended periods.

The delivery wall of the invention is made of biodegradable materials and comprises in a layered manner a carrier layer, an optional filter layer and a barrier layer. Thus, the delivery wall may comprise different parts that are arranged in plies, slats, tiers or as strata. Thereby, it is possible to provide the delivery wall with an arbitrary number of layers that each can provide a desired functionality, such as, for example, a layer for sealing, (a further layer) for forming a (moisture/gaseous (oxygen)) barrier, a bonding layer for bonding one or more layers, a protective layer, and/or for purifying and/or sieving out certain particles or contents from the prepared beverage before the prepared beverage leaves the capsule (the chamber), such as with the filter layer. Therein, the delivery wall may have various (layer) configurations, forms and shapes. The carrier layer (also called retention layer) of the delivery wall is provided such that it may be opened upon pressure rinsing in the capsule and/or interaction with opening elements of a capsule holder (of a capsule chamber of the beverage production machine) under the effect of rising pressure of the fluid injected in the capsule, for example,) by relative movement between the respective elements. Therein, the opening elements may have various configurations, forms and shapes and may comprise a plurality of relief and recessed elements, e.g. pyramid-like elements. This design allows tailoring the design of the delivery wall to technical needs.

The optional filter layer is provided for filtering out particles from the prepared beverage dispensed via the delivery wall.

Each of the filter layer and the carrier layer is made of a biodegradable, preferably compostable material. This may lead to a more straightforward recovery of the organic material inside the capsule as well as of the capsule material itself.

The barrier layer is made of biodegradable material and provides a preferably bidirectional barrier against moisture and/or gas, the barrier layer is preferably made of a different material than the filter layer and/or the carrier layer; the barrier layer being applied on the carrier layer.

In the proposed solution, the barrier properties are preferably against moisture and/or liquid and/or gaseous substance, preferably oxygen, entering and/or leaving the chamber.

Preferably, the barrier layer is preferably made of a different material than the filter layer and/or the carrier layer as the expected physicochemical properties of the barrier layer are protection of the substance enclosed in chamber against moisture and/or oxygen and not any filtering or retention properties.

Preferably, each of the filter layer, the barrier layer and the carrier layer is made of a different biodegradable and preferably compostable material, wherein preferably the different materials distinguish in at least one of their respective physical properties, such as tensile strength, ductility, elasticity, puncture resistance, density, porosity, and/or, if applicable, fibre structure and/or fibre orientation.

Therein, the expression "biodegradable material" may be understood as any material that can be broken down into environmentally innocuous products by (the action of) living things (such as microorganisms, e.g. bacteria, fungi or algae). This process could take place in an environment with the presence of oxygen (aerobic) and/or otherwise without presence of oxygen (anaerobic). This may be understood, for example, as meaning that composting can be carried out without reservation. In particular, at the end of a composting process there are no residues of the material, which may be problematic for the environment, or any non-biodegradable components.

Examples for biodegradable materials for the carrier layer or the filter layer may be different plant-based materials, such as wood, bamboo, bamboo fibres, cellulose, cellulose pulp, wood pulp, sugarcane pulp, paper and/or cardboard. In addition, bioplastic families such as polyhydroxybutyrate (PHB) and co-polymers, polybutylene succinate (PBS), poly(butylene succinate-co-butylene adipate) (PBS-A/PBSa), polylactide (PLA), polybutylene adipate terephthalate (PBAT), Cellulose Acetate, starch and/or compounds of above mentioned materials are other examples.

International standards, e.g. EU 13432 or US ASTM D6400, specify technical requirements and procedures for determining compostability of a material. Biodegradation can be tested following standards such as ISO 14855, ISO 17556 or ISO 14851. For example, one of the tests requires that - in order to be considered as being "industrially compostable" - at least 90% of the material in question is biologically degraded under controlled conditions in 6 months. Similar tests exist also to enable home composting certification.

According to the invention, the barrier layer is applied in one or more layers in a total quantity of 0,5 to 10 gsm (g/m2), preferably of 1,5 to 4 gsm (g/m2).

The proposed total barrier layer quantity allows to have sufficient barrier material to provide a barrier effect.

Additionally, the barrier layer is applied on at least one of the carrier layer's surfaces, said surface having a surface roughness lower than 1;3 microns when measured according to ISO 3274:1996.

Surface roughness, often shortened to roughness, is a component of surface texture. It is quantified by the deviations in the direction of the normal vector of a real surface from its ideal form.

Roughness measurement may use surface profile measurement using a profilometer. In the present case it is done using a contact or stylus profilometers (such as Smithers' portable Handysurf E-35B) which moves a loaded diamond probe across the surface and record the vertical movement of the stylus caused by the surface irregularities. Samples have been measured 15 times.

Controlling the roughness of the carrier layer surface before applying the barrier layer ensures regular application of the barrier layer on a material surface having more closed pores thereby improving the barrier layer properties, especially in OTR performances.

The barrier layer can additionally be applied more uniformly by covering all the carrier surface. A rougher surface could lead to "uncovered spots" that deteriorate the overall OTR perf.

According to a possible feature, the carrier layer is made of a material that is compostable and/or has a defined, preferably closed fibre structure, such as fibre structures with at least 50% of weight corresponding to softwood pulp, cellulose fibres, or paper. In a preferred solution, the carrier layer is made of paper-based material.

When the carrier layer is cellulose based, it may have a grammage comprised between 20 and 150 g/m2, preferably between 30 and 100 g/m2.

As an alternative, the closed fiber structure corresponds to Polyhydroxyalkanoate (PHA), Polyhydroxybutyrate (PHB) and co-polymers, Polybutylenesuccinate (PBS/PBS-A), biopolyesters, Cellulose Acetate, starch, polyvinyl alcohol (PVOH), polymers or co-polymers where at least one of the monomer units is vinyl alcohol, compounds and/or laminates of the above-mentioned materials.

In accordance with the use of the capsule in a beverage preparation machine capable of feeding an amount of a fluid under pressure into the capsule, the carrier layer, preferably the material of the carrier layer, is configured such that it is resilient against a built-up pressure in the chamber between 1 and 20 bar, more preferred between 10 and 20 bar, most preferred between 12 and 18 bar.

According to the needs, the characteristics of the carrier layer can be adjusted. For example, the tensile strength of the carrier layer can be improved by increasing the grammage of its material.

In a preferred embodiment, the filter layer is provided opposite to the chamber with respect to the carrier layer. This particular order and orientation of the carrier layer and the filter layer with respect to the capsule body leads to a number of improvements. For example, it is observed that the pressure profile during the beverage preparation is more consistent and reproducible. Moreover, a better crema formation and extraction and a reduced concentration of particles and residues of the substance, e.g. roast and ground of coffee, is found with this configuration in the beverage.

Resulting from the above, the carrier layer may face the chamber or may be provided closer to the chamber than the filter layer. Therein, for example, the expression "facing" may be understood as being directed towards the respective reference object without necessarily having to be provided directly onto the respective reference object.

According to a further possible feature, the filter layer is made of a compostable and/or non-woven material, such as wood or sugarcane pulp, cellulose fibres, rayon fibres, polybutylene succinate (PBS), poly(butylene succinate-co-butylene adipate) (PBS-A/PBSa), polyhydroxybutyrate (PHB) and/or Polylactic acid (PLA).

According to a further feature the filter layer has a total grammage between 10 and 150 g/m2, preferably between 20 and 100 g/m2.

Having a filter layer with a grammage between 10 and 150 g/m2, preferably between 20 and 100 g/m2 allows ensuring efficient filtering of any particle of the substance enclosed in the capsule chamber, for example roast and ground coffee.

Thereby, the characteristics of the filter layer can be set by defining their area density of material, i.e. as mass per unit of area. For example, the tensile strength of the filter layer can be improved by increasing the grammage of its material and/or by using a (non-woven) material comprising fibres of a defined length and/or with a defined fibre bonding. Moreover, the filtration capacity and/or the porosity of the filter layer can be modified, e.g. reduced to smaller particle diameters, by setting the filter layer's material characteristics accordingly. Thereby, it is possible to tailor the filter layer to the specific requirements of the beverage preparation.

In the proposed delivery wall structure, the barrier layer is applied on the surface of the carrier layer facing the chamber of the capsule body.

Additionally, the at least one barrier layer is made of a biodegradable and preferably compostable material, such as biopolymers, polyvinyl alcohol (PVOH), Butenediol vinyl alcohol copolymer (BVOH), or any vinyl alcohol co-polymers where at least one of the monomer units is vinyl alcohol, and compounds or laminates of the above-mentioned materials.

Preferably, the barrier layer is made of a different material than the filter layer and/or the carrier layer. This allows benefiting from the different material properties of both the filter layer and the carrier layer.

Hence, with the proposed delivery wall structure comprising the filter layer, the carrier layer and the barrier layer made from the previously proposed material, the Oxygen Transmission Rate (OTR) of the delivery wall (300) is below 35 cc/m²/day, measured according to ASTM D3985/ISO 15105 methodology.

Oxygen transmission rate (OTR) is the measurement of the amount of oxygen gas that passes through a substance over a given period. It is mostly carried out on non-porous materials, where the mode of transport is diffusion. In the present case, it relates to the permeation of oxygen through a packaging material (delivery wall) to sensitive foods like coffee.

OTR measurement methodology uses ASTM D3985/ISO 15105 with typical measured Test Area of 50cm2 with Analysis conditions: 23°C and 50% Relative Humidity.

The controlled surface roughness coupled to the total quantity of barrier material applied on the carrier layer allows for improved OTR performances of the delivery wall via a decrease in the OTR values. Hence a tighter capsule may be obtained.

According to a further feature the delivery wall, preferably the carrier layer further comprises a protective layer extending on the surface of the barrier layer facing the chamber of the capsule, for the protection of the barrier layer. It is thereby possible to guarantee that the barrier layer is fully protected.

The protective layer is applied in one or more protective layers in a total amount of 0.1 gsm to 10 gsm (g/m2), preferably between 2 gsm and 5 gsm (g/m2) and with a maximum total thickness of 10 microns.

The protective layer is made of a biodegradable and preferably compostable material, such as a vegetable-based starch or acrylic adhesive polymers.

Furthermore, the protective layer is preferably non hydrosoluble to avoid its degradation by the moisture content of the substance enclosed in the chamber. The protective layer is preferably made of a different material than the filter layer and/or the carrier layer to ensure proper separation of the physicochemical properties of the different layers

With this proposed improved structure of the delivery wall completed with a protective layer (applied in one or more layers), the OTR value of delivery wall of the delivery wall comprising the protective layer is less than 10 cc/m2/day.

The controlled surface roughness, the defined total quantity of barrier material applied on the carrier layer coupled with the application of a protective layer in one or more layers allows for further improved OTR performances of the delivery wall.

These improved OTR performances participate in increasing the protection of the substance filled in the capsule chamber, generally roast and ground coffee, thereby increasing the shelf-life of the capsule itself for the benefit of the consumer.

In an additional aspect, the delivery wall, preferably the protective layer, comprises, on the side that is oriented towards the chamber, an adhesive layer for joining, preferably sealing, preferably heat-sealing, the delivery wall onto the rim portion of the capsule body.

The adhesive layer is applied in one or more layers and the total grammage of the adhesive layer(s) is comprised between 0.5 to 20 g/m2 to provide sufficient adhesive material for a complete adhesion/sealing of the (periphery of the) delivery wall on the capsule rim portion.

Additionally, the adhesive layer(s) has a total thickness comprised between 1 and 30 micrometers, preferably between 10 and 15 micrometers.

The total thickness of the adhesive layer is limited when compared to the thickness of the carrier layer (ranging between 10 to 150 micrometers, preferably 30 to 70 micrometers).

In a proposed embodiment, the adhesive layer covers a maximum of 75% of the surface of the delivery wall and is at least applied around the perimeter of the delivery wall along its periphery over a radial distance D of at least 3 mm, preferably between 5 and 10 mm.

Preferably, the adhesive layer covers a maximum of 70% of the surface of the delivery wall, specifically of the carrier layer, more specifically of the protective layer. More preferably, the adhesive layer covers a maximum of 50 %, even more preferably a maximum of 30%, most preferably a maximum of 20% of the surface of the delivery wall, specifically of the carrier layer, more specifically of the protective layer.

The specific location of the adhesive layer, at least all around the perimeter of the carrier layer allows its efficient sealing onto the rim portion of capsule body and its limited extension on the surface of the carrier layer of the delivery wall ensures that the delivery wall will correctly open and that the interaction with the opening elements of the beverage preparation machine may be done without physical and/or chemical interferences to provide controlled extraction parameters.

The direct interaction of the carrier layer (and subsequent layers) with the opening elements with limited presence of the adhesive layer allows for a more effective control of the extraction parameters.

The limitation of the adhesive layer onto the surface of the carrier layer allows for an improved controlled interaction of the delivery wall with the opening elements of the beverage preparation machine.

With the proposed configuration, and especially when the surface of the delivery wall covered by the adhesive layer is low (for example below 50% of the surface of the carrier layer/protective layer), opening of the delivery wall is improved and a better and uniform extraction result can be achieved.

As mentioned, the surface of the delivery wall (or carrier layer) covered by the adhesive layer is preferably be limited to the periphery/perimeter of the delivery wall (or carrier layer) with a radial extension comprised between 3 mm to 12 mm from the perimeter edge of the delivery wall (or carrier layer).

The limitation of extension of the adhesive layer to the perimeter of the delivery wall participates in improving the opening of the delivery wall of the capsule when it is used in a beverage preparation machine as previously mentioned.

Similarly, as the carrier layer and the filter layer, the adhesive layer is of a biodegradable and preferably compostable material. For example, the adhesive layer may be a vegetable-based starch or acrylic adhesive.

In a preferred feature, the at least one adhesive layer is hydrophobic. Additionally, the adhesive layer is non-hydrosoluble to avoid any interaction with the moisture content of the beverage substance. Indeed, the beverage substance that is preferably roast and ground coffee has a resulting moisture content comprised between 2 and 4% and it is mandatory to avoid that this moisture reacts and degrades the adhesive layer. In this way, the adhesive layer is kept integral.

Preferably, the at least one adhesive layer is made of a different material than the filter layer and/or the carrier layer. Generally, this may lead to the advantageous effect that the combination of the two or more constituent materials with different physical or chemical properties produce a structure with different and added characteristics coming from each of the individual components.

As mentioned, the delivery wall also comprises a bonding layer which allows to, at least partially, join the filter layer and the carrier layer to each other on opposite sides thereof, preferably through adhesive bonding or heat-sealing.

As proposed, the bonding layer is provided between the carrier layer and the filter layer to ensure efficient adhesion of the two above-mentioned layers.

The bonding layer is of a biodegradable and preferably compostable material, such as vegetable based starch or acrylic adhesive and participate to the biodegradable properties of the complete capsule.

Preferably, the different layers forming the delivery wall, namely, the filter layer, the bonding layer, the carrier layer, the barrier layer, the protective layer and the adhesive layer, which can be each formed of one or more layers, are made of different biodegradable, preferably compostable, material.

In addition to the above, the delivery wall may comprise additional layers beside the filter layer, the carrier layer, and the adhesive layer. These additional layers may be intercalated between the filter layer, carrier and the adhesive layers as needed and depending on their function.

The different layers are preferably made of different materials that preferably distinguish in at least one of their respective physical properties, such as tensile strength, ductility, elasticity, puncture resistance, density, porosity, and/or, if applicable, fibre structure and/or fibre orientation. By providing at least the aforementioned carrier layer and filter layer from two different materials, it is possible to provide the delivery wall as a composite structure. However, it is also conceivable that the delivery wall may comprise multiple different layers, which preferably may be made from different materials. This may lead to the advantageous effect that the combination of the two or more constituent materials with different physical or chemical properties produce a structure with characteristics different from each of the individual components. Thereby, the interface of the capsule to the outside can be tailored to the technical needs of the application. For example, by providing each of the layers with a different tensile strength, the pressure built up inside the capsule can be controlled and defined as required. Thereby, for example, the capsule can be designed to produce a beverage according to the specifications of its recipe. Moreover, by providing the two layers from materials with a different fibre configuration it is possible to tailor material characteristics relevant for the interaction of the delivery wall with the prepared beverage to the individual application, such as defining the filtering capabilities of the delivery wall. Also, the difference of orientation of the individual layers of the delivery wall may lead to different stresses in the layers, which can be taken into consideration with the above configuration by selecting different materials. For example, the material of one of the layers may break at a lower pressure than the material of another layer but the structure may be kept together by the combined resistance of each material, which may support each other under the effect of pressure.

In particular, one or more of the different layers of the delivery wall, namely the carrier layer, the filter layer, the bonding layer, the adhesive layer, the barrier layer and the protective layer, is laminated with the other layers of the delivery wall. Thanks to the lamination of one or more of the mentioned layers, it is possible to produce a blank foil that is cut or punched to form the delivery wall. Depending on the dimension of the blank, several delivery walls may be formed from the same blank.

The proposed capsule body and/or the injection wall comprise a layered and/or laminated structure, and preferably the capsule body and/or the injection wall are made of preferably laminated molded pulp fiber, and/or wherein the capsule body and the injection wall are made up of separate pieces or are integrally formed, e.g., as a one-piece. This opens different manufacturing options for the capsule body and/or injection wall.

A further aspect of the present invention relates to a system for preparing a beverage comprising a capsule containing a beverage ingredient, preferably roast and ground coffee and as above described and a beverage production machine. The proposed system makes use of a beverage production machine with a fluid dispensing device capable of feeding the capsule with an amount of a fluid, such as water, with a pressure between 2 bars and 20 bars at a first end of the capsule, and with a brewing chamber, comprising a first part for hosting the capsule and a second part for closing the brewing chamber. The second part of the brewing chamber comprisies a capsule holder that comprises an opening structure (with opening elements) for engaging with the capsule at the second end of the sidewall when the brewing chamber holding the capsule is closed. The opening structure comprises a relief and recessed surface facing, in use, the delivery wall, preferably the filter layer of the capsule.

According to the proposed embodiment, the delivery wall, preferably the filter layer of the capsule when in use in the closed brewing chamber, is opened with reduced tearing by the relief and recessed surface of the opening structure, when compared with a capsule comprising an aluminium delivery wall.

An additional aspect of the present invention relates to a use of a capsule as described above for preparing a beverage in a beverage production machine having a capsule holder. So, a beverage can be prepared in an advantageous and ecologically beneficial manner.

Brief description of the Drawings

The invention is further described with reference to the following examples. It will be appreciated that the invention as claimed is not intended to be limited in any way by these examples.

Embodiments of the present invention will now be described, by way of examples, with reference to the accompanying figures in which:

Figure 1 shows a schematic exploded view of a capsule according to an embodiment of the invention.

Figure 2A shows an enlarged schematic cross-section of a section of the beverage container's delivery wall from Figure 1 including a filter layer.

Figure 2B is a graph presenting the impact of the surface roughness of the carrier layer on the OTR of the delivery wall for the delivery wall of Figure 2A. Figure 3A shows an enlarged schematic cross-section of a section of the beverage container's delivery wall from Figure 2A including protective layer.

Figure 3B is a graph presenting the impact of the number of protective layers applied on the barrier layer, on the OTR of the delivery wall for the delivery wall of Figure 3A. Figure 4 is a graph presenting the OTR values of a delivery wall according to Figure 3A depending on both the roughness of the carrier layer and the number of protective layers.

Figure 5 is a graph presenting the average maximum extraction pressure curve according to the number of protective layers applied.

Figure 6 shows an enlarged schematic cross-section of a section of a beverage container's delivery wall according to an additional proposed embodiment.

Detailed description

As used in this specification, the words "comprises", "comprising", and similar words, are not to be interpreted in an exclusive or exhaustive sense. In other words, they are intended to mean including, but not limited to.

Any reference to prior art documents in this specification is not to be considered as an admission that such prior art is widely known or forms part of the common general knowledge in the field.

The figures show different views, and aspects and features of a capsule 100 and related components of the present invention for preparing a beverage in a beverage production machine in accordance with the present invention. Figures 1 shows an exploded view of a capsule according to an embodiment of the present invention and Figure 2A, 3A and 6 shows in schematic cross-section the structure of different proposed delivery walls of the capsule of the proposed invention.

The capsule

The capsule 100 may have a composite structure and/or may be made from a composite material, which preferably may consist entirely of biodegradable and/or compostable materials. The capsule 100 comprises a capsule body 200 with a three-dimensional shape with a sidewall 210. The capsule body 200 may have any shape or form, for example the capsule body may be in the form of a cup-shaped body. For example, the capsule body 200 may have a form that is suitable for the capsule 100 being inserted in a capsule holder of a (known) beverage production machine, for example a Nespresso® beverage production machine. The capsule body 200 may have a frustoconical, truncated-, cup- or bowl-shaped form. The capsule body 200 may have a circular cross-section. Thereby, for example, pressure related forces exerting on the capsule body 200 can be absorbed.

The capsule body 200 comprises a sidewall 210. The sidewall 210 delimits a chamber 250 inside the capsule 100. The sidewall 210 may be provided such that it encloses a continuous space inside the capsule body 100. This is shown exemplarily in Figure 1.

The chamber 250 is arranged to receive and store a substance 500 for the preparation of the beverage. Therein, the substance 500 may be any type of (solid, liquid, at least partially soluble and/or percolate-able) matter of a particular or definite chemical constitution. Examples for substances 500 may be roasted ground coffee, instant coffee, tealeaves, syrup concentrate, fruit extract concentrate, a chocolate product, dehydrated edible substances, and/or combinations thereof depending on the extraction process taking place. Accordingly, examples for beverages that may be prepared may be coffee- or chocolate-based drinks, or other similar types of food. However, the above examples for the substance 500 and beverages are not to be seen as a complete enumeration. Instead, various other examples are conceivable.

The capsule body 200 may have an opening 230 to the chamber 250. The opening 230 may be on at least one of the capsule body's 200 opposite ends. For example, the substance 500 may be filled inside the capsule 100 through the opening 230. The substance 500 may fill the chamber 250 entirely. However, there may be a free space between the opening 230 and the filling level of the substance 500, which may be filled with an inert gas for keeping the substance 500 fresh. Preferably, a rim portion 211 of the sidewall 210 may delimit the opening 230. The rim portion 211 may have the form of a flange and extend from the sidewall 210, preferably away from the chamber 250. In operation, the capsule 100 may be placed on the rim portion 211 inside a capsule holder of a beverage production machine.

The sidewall 210 may be provided such that it forms a continuous mantle surface of the capsule body 200. For example, the sidewall 210 may have an inside surface facing the chamber 250 and an outside surface facing away from the chamber 250. A protective layer 400 for providing a preferably bidirectional barrier against moisture and/or oxygen for the substance 500 may be provided on the capsule body 200 and/or the sidewall 210. In Figure 1, the protective layer 400 is exemplarily illustrated as being provided as a liner on the inside surface of the sidewall 210, which may extend up to and over the rim portion 211. The protective layer 400 may be provided additionally or alternatively on the outside surface of the sidewall 210. Additionally, or alternatively, the protective layer may be provided as a coating having similar barrier properties. Therein, the protective layer 400 may be made of a biodegradable and preferably compostable material, such as biopolymers or bioplastic families such as PHB and co-polymers, PBS, PBS-A, PLA, PBAT, Cellulose Acetate, starch, PVOH, and it may include any polymers or co-polymers where at least one of the monomer units is vinyl alcohol (for example BVOH, Butenediol vinyl alcohol), as well as compounds or laminates of any of the above-mentioned materials. Preferably, the protective layer 400 may be made of a food safe material (FCS, FCMs).

For example, the capsule body 200 may be made of (laminated) (wet/dry) moulded pulp fibre. Preferably, the capsule body 200 may be made of a biodegradable and/or compostable material. The capsule body 200 may be made of a food safe material (FCS, FCMs). The capsule body 200 may comprise a layered and/or laminated structure. For example, the capsule body 200 may be relatively stiff or rigid so not to collapse during operation in a beverage production machine or during storage. The layered and/or laminated design may provide the capsule body 200 with additional rigidity and/or stiffness in comparison to other designs. Therein, the moulded pulp fibre may be a composite having an additional substrate, such as biodegradable resin, laminated on the capsule body 200. For example, a laminated structure of the capsule body 200 may be created by providing the protective layer 400 thereon. However, it is also conceivable that the capsule body 200 may comprise, for example, in addition to the protective layer 400 a further laminate film or layer.

Alternatively, the capsule body 200 may be made of paper-based material or of a paper-based material with a laminate, specifically shaped to delimit a chamber 250.

The capsule 100 comprises an injection wall 220 for injecting a fluid in the chamber 250 for preparing the beverage upon interaction of the fluid with the substance 500. This is exemplarily illustrated in Figure 1.

The injection wall 220 may be provided on an opposite end of the capsule body 200 to the opening 230. The injection wall 220 may be provided integrally or separately with the capsule body 200. Hence, the capsule body 200 and the injection wall 220 may be made up of separate pieces or may be integrally formed as a one-piece. The injection wall 220 may form a tapered end portion of the capsule body 200. The injection wall 220 may be configured to be perforated by blades of the coffee production machine such that the blades provide openings for the fluid injection. Preferably, the fluid may be a liquid or a liq uid/gas mixture, such as water or milk. As the capsule body 200, the injection wall 220 may comprise also the above-described protective layer 400. It is also conceivable, that the injection wall 220 may comprise (small) openings through which blades of the coffee production machine can enter and pierce the protective layer 400. Like the capsule body 200, the injection wall 220 may comprise a layered and/or laminated structure and may be made of (laminated) moulded pulp fibre and/or a food safe material (FCS, FCMs).

The capsule body 200 and the injection wall 220 may be provided such that the chamber 250 is closed (sealed) preferably from at least three sides as shown in Figure 1. The capsule body 200 and the injection wall 220 may be provided such that the injected fluid is dispersed evenly in the chamber 250 along the sidewall 210.

The delivery wall

The capsule 100 comprises a delivery wall 300, which is connected to the capsule body 200 to close the chamber 250. This is exemplarily indicated in Figure 1.

The delivery wall 300 is provided in a layered manner as exemplarily shown in Figure 1, 2A, 3A and 6. There is no limitation on the number of (different) layers the delivery wall 300 may have.

The delivery wall 300 is flat. The word "flat" shall mean that the delivery wall 300 extends substantially in one plane. In other words, the delivery wall 300 extends in one plane, but it can be deformed in a convex or concave plane, depending on the relative pressure between the inside and the outside of the capsule. In particular, it can happen that the ingredient contained therein (e.g., roast and ground coffee) will produce gases such as carbon dioxide over the storage period of the pod. In this case, an overpressure can be created within the capsule, which forces the - initially flat - delivery wall to bulge outside. It can also happen that the atmospheric pressure varies around the capsule, for instance if the capsule is formed, filled and sealed at a factory which is near sea level, and then said capsule is transported at a higher altitude, where the atmospheric pressure is lower. In such case, the - initially flat - delivery will deflect inwardly in a concave shape. As presented in Figure 1, the delivery wall comprises o a carrier layer 320 being adapted to be opened under the effect of rising pressure of the fluid being injected into the capsule, and o a barrier layer 340 for providing a preferably bidirectional barrier against moisture and/or gas and applied on the surface of the carrier layer 320 facing the chamber 250 of the capsule body 200.

The carrier layer 320 and the barrier layer 340 are both made of biodegradable material and are presently made of different material.

The carrier layer 320 is adapted to be opened under the effect of rising pressure of the fluid being injected in the capsule 100 during extraction in the beverage preparation machine. The carrier layer 320 may be a film, membrane or ply with a defined thickness and preferably with a substantially planar surface.

The carrier layer 320 is made of biodegradable material. Preferably, the carrier layer 320 may be made of a material that is compostable and/or a food safe material (FCS, FCMs) also. Additionally, or alternatively, the (material of the) carrier layer 320 may have a defined fibre structure, such as a closed fibre structure. For example, the carrier layer 320 material may be a fibre structure with at least 50% of weight corresponding to softwood pulp. Further examples for the material of the carrier layer 320 may be one or any combination of the group of cellulose fibres, paper, biopolyesters, PHA, PHB and co-polymers, PBS, PBS-A, PVOH and/or polymers where at least one of the monomer units is vinyl alcohol.

The carrier layer 320 may be provided such that it is resilient against a built-up pressure in the chamber 250, preferably between 1 and 20 bar, more preferred between 10 and 20 bar, most preferred between 12 and 18 bar. In particular, the material of the carrier layer 320 may be configured such that it is resilient against a built-up pressure in the chamber 250 within such pressure ranges. Therein, the thickness and density of the material may influence the stiffness, i.e., the resistance to a bend, of the carrier layer 320. The carrier layer 320 may have a thickness of material of 10 to 150 micrometers, preferably 30 to 70 micrometers. Alternatively, or additionally, the carrier layer 320 may have a grammage between 20 and 150 g/m2, preferably between 40 and 100 g/m2. Preferably, the carrier layer 320 may be attached to the (rim portion 211) capsule body 200, preferably by heatsealing or adhesive bonding. As presented in Figure 1, the delivery wall 300 also comprises a barrier layer 340 which provides a barrier against moisture and/or oxygen. The barrier is chosen to be a bidirectional barrier against moisture and oxygen to preserve the substance 500, preferably roast and ground coffee, from the moisture and oxygen present outside the capsule. The bidirectional barrier layer 340 acts against liquid and/or gaseous substances/contents entering or leaving the chamber 250. With such an arrangement, the substance 500 keeps its initial quality and does not alter over time.

The barrier layer 340 is positioned on the side of the carrier layer 320 facing the capsule opening 230. It is indeed positioned closest to the opening 230 of the capsule so as to allow keeping all the nutritional properties and aromas of the substance 500.

The barrier layer 340 may be provided in the form of a single layer or in the form of multiple layers and its total thickness may vary between 1 micrometer and 10 micrometers. The amount of barrier material in the one or more barrier layers 340 is comprised between 0,1 to 10 gsm (g/m2).

It is made of a biodegradable (preferably compostable material) such as biopolymers, polyvinyl alcohol (PVOH) or copolymers, or butanediol vinyl alcohol co-polymer (BVOH) or any polymers or co-polymers where at least one of the monomer units is vinyl alcohol, and compounds or laminates of the above-mentioned materials.

In the present case, the barrier layer is made of BVOH (Butenediol vinyl alcohol copolymer) or co-polymer. The barrier layer has a total thickness between 3 and 4 micrometers.

Figure 2A shows in cross section a delivery wall according to Figure 1 to which has been added a filter layer 310 on the side of the carrier layer 320 opposite the barrier layer 340.

The filter layer 310 may be configured to filter out particles from the prepared beverage before dispensing the same via (from) the delivery wall 300. The filter layer 310 may be a film, membrane or ply of a defined thickness (and/or with a (largely) planar surface).

The filter layer 310 is made of biodegradable material. Preferably, the filter layer 310 may be made of a material that is compostable and/or a food safe material (FCS, FCMs) also. For example, the filter layer 310 may be a non-woven material, such as cellulose fibres or PLA. Further examples may be cellulose fibres, wood pulp, sugarcane pulp, rayon fibres, PBS, PBS-A, PHB and/or PLA.

The mechanical and filtering properties of the filter layer 310 may be influenced by the thickness of the material, its density as well as its permeability for particles. The filter layer 310 may have a thickness of material of 10 to 300 micrometers, preferably 30 to 250 micrometers. Additionally, or alternatively, the filter layer 310 may have a grammage between 10 and 200 gm (g/m2), preferably between 20 and 150 gsm (g/m2).

With the proposed delivery wall embodiment, the carrier layer 320 and the filter layer 310 are provided on the capsule body 200 such that the filter layer 310 is provided opposite to the chamber 250 with respect to the carrier layer 320.

Preferably, the carrier layer 320 may face the chamber 250. Alternatively, or additionally, the carrier layer 320 may be provided in the delivery wall closer to the chamber 250 than the filter layer 310. This is exemplarily illustrated in Figure 2.

Preferably, each of the filter layer 310 and the carrier layer 320 may be made of a different biodegradable and preferably also compostable material. The different materials of the two layers may distinguish in at least one of their respective physical properties, such as tensile strength, ductility, elasticity, puncture resistance, density, porosity, and/or, if applicable, fibre structure and/or fibre orientation. For example, it may be preferred that the elasticity of the filter layer 310 may be higher than the elasticity of the carrier layer 320, as, as typical for layered structures, layers being further away from the base layer undergo larger strain during bending compared to layers being closer thereto.

The delivery wall 300 may be provided opposite to the injection wall 220 with respect to the chamber 250. The delivery wall 300 and the injection wall 220 may be provided with respect to each other such that in operation the injected fluid traverses the capsule 100 in the order of the injection wall 220, the chamber 250 (and, if available, the substance 500 contained therein), and the delivery wall 300. The chamber 250 may be fully enclosed by the delivery wall 300 (on one end), the injection wall 220 (on an opposite end thereof) and the sidewall 210 (along/surrounding the sides between the two opposite ends). The delivery wall 300 preferably entirely extends over the opening 230 overlaps (with) the rim portion 211.

In the delivery wall 300 of Figures 1 and 2A; the barrier layer 340 is applied in one or more layers in a total quantity of 0,5 to 10 gsm (g/m2), preferably of 1,5 to 4 gsm (g/m2) allowing an efficient barrier to oxygen, for example. The barrier layer 340 is furthermore applied on the surface of the carrier layer 320 that is facing the capsule chamber 250 when the delivery wall 300 is sealed onto the capsule body 200, and said surface has a surface roughness lower than 1;3 microns when measured according to ISO 3274.

As presented in Figure 2B showing the Oxygen Transmission Rate (OTR) (measured in cc/m2/day) of the delivery wall 300 presented in Figure 2A according to the surface roughness of the carrier layer 320 onto which is applied the barrier layer 340, the more the surface of the carrier layer 320 is smooth, the lower is the OTR.

In the present case, the OTR of the delivery wall should be as low as possible to improve the barrier performance of the barrier layer 340 and hence of the delivery wall 300.

As presented in the graph, the OTR value is falling from 80 cc/m2/day to 35 cc/m2/day when the roughness of the surface of the carrier layer 320 onto which the barrier layer 340 is applied is decreased from 1.3 microns to 1.1 microns.

Hence, OTR performances of the delivery wall 300 are improved when the roughness of the carrier layer surface supporting the barrier layer 340 decreases.

The OTR performance of the delivery wall can further be increased to 0.5 cc/m2/day when the roughness of the carrier layer surface is dropped to 0.6 microns. However, with such limited roughness of the carrier layer surface, the surface is very smooth with very closed pores and the delivery wall may be difficult to pierce during extraction.

Reduced roughness of the carrier layer surface may be obtained using different methods. For example, the skilled person may use :

A mechanical treatment to smooth the carrier layer surface, for example with the use of abrasive cylinders having abrasive parameters adapted to the required result, or A chemical treatment, in particular an acid treatment, from example using such sulfurization process to close and reduce pore sizes.

Figure 3A shows in cross section the delivery wall of Figure 2A to which has been added a protective layer 350 in the form of a protective lacquer. As shown, the protective layer 350 extends on the side of the barrier layer 340 opposite the carrier layer 320 (i.e. facing the chamber 250 of the capsule body 200 when the delivery wall is attached to the capsule body). This protective layer 350 aims at protecting the barrier layer 340 against moisture. It may be applied in one or more layers in a total amount of 0.1 to 10 gsm with a maximum total thickness of 10 microns.

The protective layer 350 may be made from a material that is preferably nonhydrosoluble and is made of a biodegradable and preferably compostable material, such as acrylic polymers.

Figure 3B shows the impact of the number of layers of protective lacquer 350 on the OTR performance of a delivery wall 300 as presented in Figure 3A in which the roughness of the carrier layer surface has not been controlled and is therefore higher than 1.3 microns.

As can be seen, the OTR value drops significantly, from 35 cc/m2/day to 9.7 cc/m2/day between a delivery wall have one layer of protective lacquer and a delivery wall having two layers of protective lacquer 350.

The OTR value drops even more (to 0.1 cc/m2/day) when the delivery wall comprises 5 layers of protective lacquer 350 applied on the barrier layer 340.

Figure 4 is a diagram showing the impact of both the surface roughness of the carrier layer onto which the barrier layer is applied, and the number of protective layers applied onto the surface of barrier layer (opposite the carrier layer) on the OTR performances.

In the first set, the barrier layer 340 is applied on a carrier layer surface which roughness is not controlled meaning a surface roughness that is higher than 1.3 microns. As can be seen, the OTR value drops from 35 cc/m2/day to 9.7 cc/m2/day with the application of a second layer of protective lacquer. The OTR is reduced of a factor of 3.7.

In the second set, the barrier layer 340 is applied on a carrier layer surface which roughness is controlled to be less than 1.3 microns. As presented, the OTR value drops from 17.4 cc/m2/day to 1.3 cc/m2/day with the application of a second layer of protective lacquer. In this configuration, the OTR is reduced of a factor of 13.3.

As understood, both parameters, roughness of the carrier layer's surface and the number of protected layers applied on the barrier layer, have an impact on the OTR performance by a reduction of the OTR of the delivery wall.

However, as shown above, the combination of both parameters allows achieving reduction in OTR that is higher than the combined reduction of each parameter. Figure 5 presents a graph showing the maximum pressure (Pmax expressed in bars) of the pump (corresponding to the pressure in the extraction chamber) during extraction of a capsule comprising a delivery wall according to the one of Figure 3A in which the number of layers of protective lacquer varies with a controlled surface roughness of the carrier layer (meaning that it is less than 1.3 microns).

As can be seen, when the delivery wall comprises one protective layer, the maximum pressure applying during the extraction process is around 15 bars, when the delivery wall comprises two protective layers, Pmax raises to about 17.5 bars.

It could be envisaged to add as more layers of protective lacquer on the barrier layer, as possible, however, as visible on Figure 5, this has an impact on the extraction process and one the pressure exceeds a certain threshold (Pmax threshold around 18 bars), the beverage preparation machine stops due to the reaching of the maximum acceptable pressure in the machine and the extraction ceases.

Hence in order to have an improved and maximized OTR performance of the delivery wall while keeping an optimized extraction and a good system performance, it is necessary to in addition to controlling the surface roughness of the carrier layer of the delivery wall, to optimize the number of protective layers and/or the quantity of the protective layer applied on the barrier layer.

An optimized proposed combination may be:

Roughness of the carrier layer's surface holding the barrier layer: 1.1 micron, Number of protective layers: between 2 and 3 corresponding to a maximum total quantity of protective material of 6 gsm.

With the above proposed combination, the OTR performances are increased and the OTR value of the delivery wall is less than 10 cc/m2/day which is an important achievement for compostable membrane that are mainly cellulose based.

The delivery wall 300 may comprise additional layers beside the filter layer 310, the carrier layer 320, the barrier layer 340 and the protective layer 350. These additional layers may be intercalated between different layers or may constitute the most external layer of the delivery wall as needed and depending on their function.

For example, Figure 6 as already presented, proposes an optimized delivery wall 300 based on the delivery walls discussed in connection with Figure 2A and 3A. 1 As proposed in Figure 6, a bonding layer 360 is interposed between the carrier layer 320 and the filter layer 310 to join them through adhesive bonding or heat-sealing.

Hence, the carrier layer 320 and the filter layer 310 are at least partially joined to each other on opposite sides thereof, i.e. on their sides facing each other thanks to the bonding layer 360.

The bonding layer 360 is made of one or more bonding layers and provides adhesive bonding between the carrier layer 320 and the filter layer 310 to ensure efficient adhesion of the two above-mentioned layers.

The bonding layer is also of a biodegradable and preferably compostable material, such as vegetable based starch or acrylic adhesive and participate to the biodegradable properties of the complete capsule.

Bonding strength of the bonding layer 360 may vary depending on the material of the filter layer 310 and carrier layer 320.

In Figure 6, the delivery wall 300 further comprises at least one adhesive layer 330 for adhesion of the delivery wall 300 to the capsule body 200. As mentioned, and as a one-piece element, the delivery wall 300 may be connected to the rim portion 211 of the capsule body 200 to close the chamber 250, thereby forming a closed capsule 100. This may be accomplished, for example, by heat-sealing or adhesive connection. Therefore, an adhesive layer 330 may be provided between the delivery wall 300 and the capsule body 200, with which (adhesive layer) the capsule body 200 and the delivery wall 300 may be attached (joined) to each other.

More precisely and as represented in Figure 6, the adhesive layer 330 is provided on the protective layer 350.

The adhesive layer 330 may comprise of one or more adhesive layers 330a, 330b ..., as shown in Figure 6 and may be integrated in the delivery wall 300, especially if integrated into a laminated structure.

The total thickness of the adhesive layer 330, applied in one or more layers 330a, 330b, is between 1 and 30 micrometers, preferably between 10 and 15 micrometers. In the proposed embodiment, the thickness is around 10 to 13 micrometers. The material forming of the adhesive layer may be a biodegradable (and preferably compostable) material, such as vegetable based starch or acrylic adhesive. In the present embodiment the adhesive layer 330 is a polymer made of acrylic adhesive.

From the above description, the adhesive layer 330 is hence made of a different material than the filter layer 310 and/or the carrier layer 320.

This material of the adhesive layer is hydrophobic.

Additionally, the selected material is non-hydrosoluble to avoid any interaction with / degradation by the moisture content of the beverage substance 500 which may be, for example, roast and ground coffee.

This material is applied, as previously mentioned, in one or more layers. The total amount of adhesive material applied on the perimeter of the carrier layer is comprised between 0,5 and 20 gsm. This ensures that sufficient adhesive material is applied on the carrier layer 320 for an efficient tight sealing of delivery wall 300 on the rim portion 211 of the capsule body 200.

The one or more adhesive layer may be applied as coating, for example, a waterbased coating.

As can be seen in Figures 6, the adhesive layer 330 does not cover the full surface of the delivery wall 300. The adhesive layer has a limited radial extension (starting from the periphery of the delivery wall) and extends solely on the periphery of the carrier layer, all around its perimeter. The extension of the adhesive layer 330 on the perimeter of the carrier layer 320 over at least a radial distance D.

The radial distance D has to be at least equal, preferably a bit bigger than the radial extension of the rim portion 211 on which the delivery wall 300 is sealed. In the proposed embodiment of Figure 4, the radial distance D of extension of the adhesive layer is comprised between 3 mm and 12 mm, preferably between 5 to 10 mm, so that a proper sealing of the periphery of the carrier layer on the rim portion 211 is provided.

Additionally, it can be proposed that the maximum coverage percentage of the surface of the carrier layer by the adhesive layer is 90%.

In the proposed embodiment, the adhesive layer 330 clearly covers less than 50% of the surface of the carrier layer. As shown in figure 6, the (one or more) adhesive layer 330 is only applied on the periphery of the carrier layer 320, all around its perimeter over a radial distance D of about 7 mm. This radial distance D may vary between 3 and 12 mm, however, it is preferably limited in extension to a value that is slightly more than the rim portion radial extension. As exemplified, there is no adhesive layer at the center of the carrier layer to enable easier opening of delivery wall 300 and interaction with the opening elements of a beverage production machine for improved control of the extraction parameters.

The surface of the carrier layer 320 covered by the adhesive layer 330 may be limited to the periphery of the delivery wall with an extension of a radial distance D from the perimeter edge of the carrier layer 320 of the delivery wall 300. However, other valuable configurations may be implemented.

In the proposed embodiments, the adhesive layer is a heat-sealing layer 330 that can be sealed on the rim portion 211 by local heat application. The sealing of the delivery wall 300 on the rim portion of the capsule 100 is done all around the perimeter of the delivery wall.

The above presented additional layers are not impacting neither reducing the previously presented results concerning the OTR performances of the delivery wall.

Hence a delivery wall 300 according to the embodiment of Figure 6 having improved OTR performances with an OTR of less than 10 cc/m2/day, may be used in connection with the above described capsule body 200 to provide a capsule 100 having improved shelf life and optimized extraction.

Manufacturing process of the capsule

A further aspect of the present invention relates to a process for manufacturing the above-described capsule 100.

Therein, the capsule body 200 is formed from a biodegradable pulp material, such as cellulose pulp, bamboo pulp, bagasse pulp or wood pulp. The injection wall 220 is formed (preferably along with the capsule body 200) such that at least a part of the chamber 250 for receiving the substance 500 for the preparation of the beverage is formed. The delivery wall 300 is provided and attached to the capsule body 200, e.g., by heat sealing. Therein, the delivery wall 300 is provided on the capsule body 200 such that the filter layer 310 is provided opposite to the chamber 250 with respect to the carrier layer 320.

Preferably, the capsule body 200 may be formed by wet pulp moulding. Therein, a slurry of biodegradable pulp material, such as wood pulp, bagasse pulp, non-wood pulp, and/or cellulose based pulp in any form, may be pressed into a mould to form the capsule body 200. Thereafter, the so formed capsule body 200 is dried. At least a part of the inside surface (prior to filling) or at least a part of the outside surface of the capsule body 200 may be provided with the protective film 400, e.g., by thermoforming.

Alternatively, the capsule body 200 may be formed by dry pulp molding. Therefore, a blank of preferably dried cellulose fibres may be provided, from which the capsule body 200 is formed with a tool preferably under the application of heat and/or water. The protective film 400 may be applied as a liner on the inside of the capsule body 200 (for example by applying heat and/or a vacuum), which may extend on and cover the inwards facing surface of the sidewall 210 between both ends of the capsule body 200 and may extend and cover the rim portion 211 on its surface facing away from the chamber 250.

In both of the two aforementioned processes, the injection wall 220 may be formed along with the capsule body 200, e.g., in the same step. Preferably, the injection wall 220 may be formed either by (wet/dry) pulp molding or by attachment, e.g., with a biodegradable adhesive, of a membrane or film as the injection wall 220 to the capsule body 200 after forming of the capsule body 200. For example, by (wet/dry) pulp molding the injection wall 220 may be formed together with the capsule body 200 in the same process step while a second, separate process step may be needed for attaching the injection wall 220 with an adhesive. The capsule body 200 may be filled with the substance 500 for the preparation of the beverage. The delivery wall 300 may be provided and attached to the capsule body 200 thanks to the adhesive layer 330 such that the carrier layer 320 may face (be directed towards) the chamber 250. The protective film 400 may be added to a (circumferential) surface of the capsule 100, which is preferably made from a biodegradable and/or compostable material. At least a part of an inner facing or of an outer facing surface of the injection wall 220 (a surface which in addition may delimit the chamber 250) may be provided with the protective film 400.

As disclosed, the disclosed delivery wall 300 is hence composed of different layers of material each having specific properties and function and that are as a whole participating to the final properties of the delivery wall 300. The delivery wall 300 may then comprise a layered structure or be proposed as laminated structure. The general laminating manufacturing process is known in the prior art.

The specific arrangement of the one or more adhesive layer 330 on the protective layer 350 or on the barrier layer 340 may be done using coating technology or printing technologies. If a coating is applied, the coating is, for example, water-based.

System incorporating the capsule and use of the capsule

A further aspect of the invention relates to a system comprising the above-described capsule 100 and a beverage production machine and to the use of the above-described capsule 100 for preparing a beverage in a beverage production machine having a capsule holder.

For example, the capsule 100 as described above may be provided and inserted in a brewing chamber of the beverage production machine. The brewing chamber comprises a first part for hosting the capsule and a second part comprising a capsule holder having an opening structure. During the extraction process, the capsule 100 is placed in the beverage production machine such that the filter layer 310 is closer to (and eventually contacts) the opening structure (comprising opening elements in the form of a relief and recessed surface) of the capsule holder of the second part of brewing chamber of the machine than the carrier layer 320. The brewing chamber is then closed.

The injection wall 220 of the capsule 100 may be perforated by an injection nozzle of the beverage production machine to inject a fluid in the chamber 250 to interact with the substance 500. The fluid, such as a liquid or a liquid/gas mixture, may be injected into the chamber 250, thereby causing a pressure to build up in the capsule 100 and the delivery wall 300 is to thrust against opening elements, e.g. of the beverage production machine. At least part of the delivery wall 300 may be opened when the pressure of the injected fluid reaches a predetermined level in the chamber 250. Preferably, the carrier layer 320 may be perforated. Alternatively or additionally, the delivery wall 300 may be provided such (e.g. with regards to its material configuration/selection) that the carrier layer 320 may be perforated while the filter layer 310 is not perforated. In this preferred embodiment, the carrier layer 320 is perforated while the filter layer 310 remains integral. The prepared beverage may be drained from the capsule 100, wherein the beverage may pass through openings in the carrier layer 320 and (cavities in the porous material of) the filter layer 310, wherein the carrier layer 320 may be closer to the chamber 250 than the filter layer 310 and the filter layer 310 is provided opposite to the chamber 250 with respect to the carrier layer 320.

The delivery wall 300 of the capsule in use in the closed brewing chamber is thus opened with reduced tearing by the relief and recessed surface of the opening structure, when compared with a capsule comprising an aluminium delivery wall.

As previously mentioned, the invention is also related to the use of a capsule and system as above described

It should be understood that various changes and modifications to the presently preferred embodiments of the capsules described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the scope of the present invention covered by the appended claims.

In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word 'comprising' does not exclude the presence of other elements or steps then those listed in a claim. Furthermore, the terms "a" or "an," as used herein, are defined as one or more than one. Also, the use of introductory phrases such as "at least one" and "one or more" in the claims should not be construed to imply that the introduction of another claim element by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim element to inventions containing only one such element, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an." The same holds true for the use of definite articles. Unless stated otherwise, terms such as "first" and "second" are used to arbitrarily distinguish between the elements such terms describe. Thus, these terms are not necessarily intended to indicate temporal or other prioritization of such elements. The mere fact that certain measures are recited in mutually different claims does not indicate that a combination of these measures cannot be used to advantage.

Unless otherwise explicitly stated as incompatible, or the physics or otherwise of the embodiments, example or claims prevent such a combination, the features of the foregoing embodiments and examples, and of the following claims may be integrated together in any suitable arrangement, especially ones where there is a beneficial effect in doing so. This is not limited to only any specified benefit, and instead may arise from an "ex post facto" benefit. This is to say that the combination of features is not limited by the described forms, particularly the form (e.g. numbering) of the example(s), embodiment(s), or dependency of the claim(s). Moreover, this also applies to the phrase "in one embodiment", "according to an embodiment" and the like, which are merely a stylistic form of wording and are not to be construed as limiting the following features to a separate embodiment to all other instances of the same or similar wording. This is to say, a reference to 'an', 'one' or 'some' embodiment(s) may be a reference to any one or more, and/or all embodiments, or combination(s) thereof, disclosed. Also, similarly, the reference to "the" embodiment may not be limited to the immediately preceding embodiment.

The foregoing description of one or more implementations provides illustration and description but is not intended to be exhaustive or to limit the scope of the invention to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practice of various implementations of the present disclosure.

Claims

1. A capsule (100) for preparing a beverage in a beverage production machine, wherein the capsule (100) comprises:

- a capsule body (200) comprising a sidewall (210) delimiting a chamber (250) for containing a substance (500) for the preparation of the beverage, and a rim portion (211) delimiting an opening (230) in the sidewall (210);

- an injection wall (220), closing the chamber at a first end, for injecting a fluid in the chamber (250) for preparing the beverage upon interaction of the fluid with the substance (500); and

- a delivery wall (300) being connected to the capsule body (200), preferably to the rim portion (211), to close the chamber (250) at a second end of the capsule body (200), the delivery wall (300) comprising in a layered manner: o a carrier layer (320) made of biodegradable material, the carrier layer (320) being adapted to be opened under the effect of rising pressure of the fluid being injected into the capsule (100), and o optionally a filter layer (310) made of biodegradable material for filtering out particles from the prepared beverage dispensed via the delivery wall (300), o a barrier layer (340) made of biodegradable material for providing a preferably bidirectional barrier against moisture and/or gas, the barrier layer (340) being preferably made of a different material than the filter layer (310) and/or the carrier layer (320); the barrier layer (340) being applied on the carrier layer (320). wherein the barrier layer (340) is applied in one or more layers in a total quantity of 0,5 to 10 gsm (g/m²), preferably of 1,5 to 4 gsm (g/m²) and is applied on least one of the carrier layer's surfaces, said surface having a surface roughness lower than 1,3 microns when measured according to ISO 3274.

2. The capsule (100) according to claim 1, wherein, in the layered delivery wall (300), the carrier layer (320) is provided on the side facing the chamber (250) and the filter layer (310) is-provided opposite to the chamber (250) with respect to the carrier layer (320).

3. The capsule (100) according to any one of the preceding claims, wherein the carrier layer (320) is made of a material that is compostable and/or has a defined, preferably closed fibre structure, such as fibre structures with at least 50% of weight corresponding to softwood pulp, cellulose fibres, paper or Polyhydroxyalkanoate

(PHA), Polyhydroxybutyrate (PHB) and co-polymers, Polybutylenesuccinate (PBS/PBS- A), biopolyesters, Cellulose Acetate, starch, polyvinyl alcohol (PVOH), polymers where at least one of the monomer units is vinyl alcohol, compounds and/or laminates of the above mentioned materials, and/or wherein the carrier layer (320) has a grammage between 20 and 150 g/m², preferably between 30 and 100 g/m².

4. The capsule (100) according to any one of the preceding claims, wherein the filter layer (310) is made of a compostable and/or non-woven material, such as wood or sugarcane pulp, cellulose fibres, rayon fibres, polybutylene succinate (PBS), poly(butylene succinate-co-butylene adipate) (PBS-A/PBSa), polyhydroxybutyrate

(PHB) and/or Polylactic acid (PLA), and/or wherein the filter layer (310) has a grammage between 10 and 150 g/m², preferably between 20 and 100 g/m².

5. The capsule (100) according to any one of the preceding claims, wherein the barrier layer (340) is applied on the surface of the carrier layer (320) facing the chamber (250).

6. The capsule (100) according to any one of the preceding claims, wherein the barrier layer (340) provides a preferably bidirectional barrier against moisture and/or oxygen, wherein the at least one barrier layer (340) is made of a biodegradable and preferably compostable material, such as biopolymers, polyvinyl alcohol (PVOH), butanediol vinyl alcohol co-polymer (BVOH ) or any vinyl alcohol co-polymers where at least one of the monomer units is vinyl alcohol, and compounds or laminates of the above mentioned materials, and wherein the barrier layer (340) is preferably made of a different material than the filter layer (310) and/or the carrier layer (320).

7. The capsule (100) according to any one of the preceding claims, wherein the Oxygen Transmission Rate (OTR) of the delivery wall (300) is below 35 cc/m²/day, measured according to ASTM D3985/ISO 15105 method.

8. The capsule (100) according to any one of the preceding claims, wherein the delivery wall (300) further comprises a protective layer (350) preferably extending on the barrier layer (340) and applied in one or more protective layers in a total amount of 0.1 to 10 gsm (g/m2), preferably between 2 and 5 gsm (g/m2) and with a maximum total thickness of 10 microns

9. The capsule (100) according to claim 8, wherein the protective layer (340) is preferably non hydrosoluble and is made of a biodegradable and preferably compostable material, such as vegetable based starch or acrylic polymers.

10. The capsule (100) according to any one of claims 1 to 7 in combination with one of claims 8 or 9, wherein the OTR value of delivery wall of the delivery wall (300) comprising the protective layer (340) is less than 10 cc/m2/day measured according to ASTM D3985/ISO 15105 method.

11. The capsule (100) according to anyone of claims 1 to 7 in combination with anyone of claims 8 to 10, wherein the delivery wall (300) further comprises an adhesive layer (330), applied in one or more layer and being positioned on the side of the delivery wall (300) oriented towards the chamber (250), preferably on the surface of the protective layer (340) and/or comprises a total amount comprised between 0.5 and 20 gsm and has a total thickness between 1 micrometer and 30 micrometers, preferably between 10 micrometers and 15 micrometers

12. The capsule (100) according to claim 11, wherein the adhesive layer (330) covers a maximum of 75 % of the delivery wall and is at least applied around the perimeter of the delivery wall (300), along its periphery, over a radial distance D comprised between 3 mm and 12 mm, preferably between 5 mm and 10 mm.

13. The capsule (100) according to claim 11 or 12, wherein the adhesive layer (330) is a sealing layer (330) made of biodegradable and preferably compostable material, such as vegetable based starch or acrylic adhesive, preferably a heat-sealing layer, for sealing the delivery wall (300), preferably the periphery of the delivery wall (300), to the rim portion (211) of the capsule body (200).

14. The capsule (100) according to any one of the preceding claims, wherein the carrier layer (320) and the filter layer (310) are at least partially joined to each other on opposite sides thereof, preferably through adhesive bonding or heat-sealing, using a bonding layer (360) provided between the carrier layer (320) and the filter layer (310) that is of a biodegradable, preferably compostable, material, such as vegetable based starch or acrylic adhesive.

15. The capsule (100) according to any one of the preceding claims, wherein the capsule body (200) and/or the injection wall (220) comprise a layered and/or laminated structure, and wherein preferably the capsule body (200) and/or the injection wall (220) are made of preferably laminated molded pulp fiber, and/or wherein the capsule body (200) and the injection wall (220) are made up of separate pieces or are integrally formed, e.g., as a one-piece.

16. The capsule (100) according to any one of the preceding claims, wherein the capsule body (200) is made of cellulose-based pulp-molded material, preferably wood-based pulp-molded material.

17. System for preparing a beverage comprising a capsule according to anyone of claims 1 to 16 and a beverage production machine with a fluid dispensing device capable of feeding the capsule with an amount of a fluid, such as water, with a pressure between 2 bars and 20 bars at a first end of the capsule, and with a brewing chamber, comprising a first part for hosting the capsule and a second part for closing the brewing chamber, wherein the second part of the brewing chamber comprises a capsule holder comprising an opening structure for engaging with the capsule at the second end of the sidewall when the brewing chamber holding the capsule is closed, the opening structure comprising a relief and recessed surface facing, in use, the delivery wall (300), preferably the filter layer (310) of the capsule, wherein the delivery wall (300), preferably the filter layer (310) of the capsule in use in the closed brewing chamber is opened with reduced tearing by the relief and recessed surface of the opening structure, when compared with a capsule comprising an aluminium delivery wall.

18. Use of a capsule (100) according to any one of the preceding claims 1 to 16, in a system for preparing a beverage according to claim 17, for preparing a beverage in a beverage production machine having a capsule holder.