Biodegradable top membranes for beverage capsules.

Abstract

The present invention relates generally to the field of beverage capsules. Specifically, the present invention relates to a biodegradable upper membrane for a beverage capsule. The biodegradable upper membrane for a beverage capsule is pierceable by an injection means of a beverage preparation machine adapted to inject an extract under pressure into a sealed chamber containing a mass of soluble and / or extractable food material. Notably, the upper membrane is biodegradable yet possesses the necessary physical properties to be useful in a beverage capsule. The biodegradable upper membrane for a beverage capsule comprises at least one polyhydroxyalkanoate (PHA).

Description

Detailed Description of the Invention

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[0004]

[0001] The present invention generally relates to the field of beverage capsules. Specifically, the present invention relates to a biodegradable upper film of a beverage capsule. The biodegradable upper film of the beverage capsule is perforable by the injection means of a beverage preparation machine adapted to inject an extract under pressure into a sealed chamber containing a mass of soluble and / or extractable food material. Notably, this upper film is biodegradable while having the physical properties necessary to be useful in a beverage capsule. The biodegradable upper film for a beverage capsule contains at least one polyhydroxyalkanoate (PHA).

[0002] The beverage preparation machine enables consumers to prepare various types of beverages, such as coffee-based beverages, at home.

[0003] Today, most home beverage preparation machines for home use include a system consisting of a machine capable of accommodating portioned raw materials for beverage preparation. Such portions can be soft pods or pads or bags, but systems using semi-rigid or rigid portions such as rigid pods or capsules are becoming increasingly common. Hereinafter, the beverage machine of the present invention is considered to be a beverage preparation machine that handles rigid capsules.

[0004] This machine includes a container for accommodating the capsule and a fluid injection system for injecting a fluid, preferably water, into the capsule under pressure. The water injected into the capsule under pressure for the preparation of coffee beverages is preferably at a high temperature, i.e., a temperature exceeding 70°C. However, in some specific examples, the water may be at ambient temperature. The pressure in the capsule chamber during extraction and / or dissolution of the capsule contents is typically about 1 to 8 bar in the case of a dissolved product (in the case of dissolution of soluble raw materials such as powdered milk, chocolate powder, instant coffee or instant tea), and about 2 to 12 bar in the case of extraction of roasted and ground coffee.

[0005] The principle of extracting and / or dissolving the contents of a sealed capsule under pressure is well known and typically involves pressing the capsule into a machine container, puncturing the surface of the capsule with a puncture injection element, such as a fluid injection needle attached to the machine, so as to create a pressurized environment inside the capsule for either the extraction or dissolution of a substance, then injecting a certain amount of pressurized water into the capsule, and subsequently releasing the extracted or dissolved substance from the capsule. Capsules that enable the application of this principle have already been described, for example, in European Patent No. 1472156 and European Patent No. 1784344. These capsules have the specific feature of enclosing beverage ingredients in a chamber closed by an upper membrane into which water is injected and a lower membrane configured to open further in response to an increase in water pressure within the chamber. Once liquid is injected into the chamber, the pressure deforms the lower membrane until an opening element positioned close to the lower membrane penetrates the deformed membrane, and the beverage prepared in the chamber falls outwards from the capsule, for example into a cup.

[0006] As mentioned above, these capsules are rigid capsules typically made of plastic material.

[0007] Packaging of processed foods is a crucial part of today's food industry, as it plays a vital role in ensuring food safety, maintaining food quality, and in the manufacturing process, brand communication, and digitalization. In fact, several studies have shown that for most consumers, product packaging is one of the key factors influencing their purchasing decisions.

[0008] One of the main problems associated with packaging is, in general, the generation of packaging waste. According to Eurostat, in 2017, 172.6 kg of packaging waste was generated per person in the EU.

[0009] Industry is addressing this issue by introducing a circular economy. In line with this, the European Commission recently delivered a new circular economy action plan (Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions: A new Circular Economy Action Plan For a cleaner and more competitive Europe, Brussels, 11.3.2020). Therefore, the EU needs to accelerate its transition to a regenerative growth model that gives back to the planet rather than depletes it, move towards keeping resource consumption within the planet's sphere of influence, and ultimately reduce the consumption of natural resources while striving to double the use of circular materials in the next decade.

[0010] One step towards achieving this is to provide sustainable food packaging. Such sustainability can be achieved through recyclable and / or biodegradable food packaging.

[0011] The object of the present invention was to enhance or improve upon the latest technology, specifically to provide a biodegradable upper membrane for beverage capsules having the necessary properties to withstand heat and pressure during beverage extraction without causing undesirable deformation or other adverse effects during beverage preparation, or to provide at least a useful alternative to current existing solutions.

[0012] The inventors have surprisingly found that the object of the present invention can be achieved by the subject matter of the independent claim. The dependent claim further develops the idea of ​​the present invention.

[0013] In the first embodiment, the capsule described in claim 1 is provided.

[0014] This capsule comprises a capsule body for containing beverage ingredients, an upper membrane, a lower membrane, and an opening device.

[0015] The main body of this capsule is The chamber is defined, with an axially extending side wall between the upper opening and the lower outlet from which the beverage is supplied. The device comprises a circumferential annular flange projecting radially outward from an upper opening, the circumferential annular flange having an upper surface on the opposite side of the chamber relative to the opening, and a lower surface on the opposite side.

[0016] Preferably, the capsule body is made of a biodegradable or compostable material such as polylactic acid (PLA), polyhydroxyalkanoate (PHA), polybutylene succinate (PBS), polybutylene succinate adipate (PBSA), and / or polybutylene adipate terptalate (PBAT).

[0017] The upper membrane of this capsule is attached to at least a portion of the upper surface of the circumferential flange of the capsule body, and is fitted to close the upper opening and to be punctured when injecting liquid into the capsule.

[0018] The upper membrane is biodegradable and comprises at least one film consisting of at least one polyhydroxyalkanoate (PHA).

[0019] The lower membrane of the capsule is located inside the chamber. Together with the upper membrane, the lower membrane defines the beverage ingredient chamber, which is filled with beverage ingredients. These beverage ingredients may be soluble or extractable beverage ingredients.

[0020] The capsule opening device is located inside the chamber and beneath the lower membrane. It is designed to open the capsule by engaging with the lower membrane under the influence of the pressure increase caused by the liquid injected into the raw material chamber.

[0021] Preferably, the opening device is made of a biodegradable or compostable material.

[0022] Preferably, the entire capsule is made of a biodegradable or compostable material.

[0023] As used herein, the words “comprises,” “comprising,” and similar words should not be interpreted as exclusive or exhaustive. In other words, they are intended to mean “includes, but not limited to.”

[0024] The inventors have shown that a biodegradable upper membrane for beverage capsules, comprising at least one polyhydroxyalkanoate (PHA), achieves the objectives of the present invention.

[0025] The inventors have achieved particularly good results using a top membrane comprising a layer containing PHA blended with a biopolymer and a layer containing polybutylene succinate (PBS). In one preferred embodiment of the present invention, the top membrane comprises a layer containing PBS sandwiched between two layers containing PHA blended with a biopolymer.

[0026] Figure 4 shows an example of the membrane structure of the biodegradable upper membrane according to the present invention, which was prepared by the inventors and achieves the objectives of the present invention.

[0027] Accordingly, the present invention relates, in part, to a biodegradable top membrane for a beverage capsule comprising at least one polyhydroxyalkanoate (PHA). The biodegradable top membrane is perforated by an injection means of a beverage preparation machine adapted to inject an extract under pressure into a sealed chamber containing a mass of soluble and / or extractable food material. The sealed chamber containing the mass of soluble and / or extractable food material may be part of the beverage capsule or may be the beverage capsule itself.

[0028] The injection means of the beverage preparation machine pierces the upper membrane. The injection means may be, for example, one or more liquid injection hollow needles. When the liquid is injected into the capsule compartment, the pressure rises, which functions as extraction means for extracting a mass of soluble and / or extractable food material contained in the capsule.

[0029] PHA is well known in the art. PHA is attracting increasing attention in the biodegradable polymer market due to promising properties such as high biodegradability in various environments not only in composting plants and processing versatility. See, for example, eXPRESS Polymer Letters Vol.8, No.11 (2014) 791 - 808.

[0030] Many PHAs are commercially available. For example, with respect to the upper membrane of the present invention, at least one PHA can be selected from the group consisting of P(3HB - co - 3HV), PHB copolymer, P(3HB - co - 3HHx), P(3HB - co - 4HB), P(3HB), P(3HB - co - 3HV), P(3HB - co - 3HO), P(3HB - co - 3Hod) or combinations thereof.

[0031] The biodegradable upper membrane can be composed of a sealant layer having at least 30% by weight of PHA. The inventors have found that this ensures sealing during extraction.

[0032] For example, when the injection means is withdrawn from the capsule after injecting hot water into the capsule under pressure, it is essential for the upper membrane to close the perforation created by the injection means again. Otherwise, due to the residual pressure remaining in the capsule compartment after the capsule has been used, a jet of liquid (often called the "whale effect") may jet out from the upper capsule membrane through the hole perforated by the injection means. Such a whale effect occurs randomly and rarely, but is undesirable because it can cause accidents and lack of cleanliness.

[0033] A thicker upper membrane is more effective at preventing this whale effect than a thin upper membrane. On the other hand, a thin upper membrane biodegrades faster than a thicker upper membrane.

[0034] Preferably, the upper membrane can withstand a fluid pressure of at least 1 bar, preferably at least 3 bar, and more preferably at least 5 bar, without leakage after the fluid injection means has been removed therefrom.

[0035] The inventors have found that when the biodegradable upper film has a material thickness in the range of approximately 120 to 150 μm, optimal biodegradability can be ensured while effectively avoiding the whale effect.

[0036] One or more barrier layers may be added on top of the PHA-containing layer. Furthermore, a printed layer may be added, for example, since many beverage capsules use a coding system to ensure optimal beverage extraction conditions. Such a coding system is described, for example, in European Patent No. 3107433.

[0037] The top membrane must also withstand certain pressures during the injection process. For example, in the case of coffee, such a beverage extraction machine injects hot water into the capsule under high pressure, and the coffee powder is extracted under high pressure for several seconds. Therefore, the biodegradable top membrane according to the present invention may be able to withstand pressures of at least 7 bar, at least 9 bar, or at least 11 bar. The biodegradable top membrane according to the present invention may be able to withstand such pressures for at least 5 seconds, at least 10 seconds, or at least 15 seconds.

[0038] Extraction can be carried out using a fluid with a volume of approximately 5 to 250 ml, for example, 10 to 100 ml, such as water. If the beverage to be extracted is Listerotto, the volume of water may be in the range of 20 to 30 ml. If the beverage to be extracted is espresso, the volume of water may be in the range of 30 to 50 ml. If the beverage to be extracted is a double espresso, the volume of water may be in the range of 50 to 100 ml. If the beverage to be extracted is a coffee lungo, the volume of water may be in the range of 100 to 150 ml.

[0039] During the extraction process, a foam layer may form inside the capsule and on the resulting beverage. For example, the upper membrane may be able to withstand process conditions that allow for the generation of an average foam height in the range of approximately 2–5 mm, for example, in the range of approximately 3–4 mm, on the beverage being extracted.

[0040] Advantageously, the biodegradable upper membrane according to the present invention may include an elastic material having a Young's modulus of less than 150 GPa. Due to the elasticity of the material, the upper membrane can be easily penetrated and deformed when the liquid injection means of the machine is moved. Next, after the liquid has been injected into the capsule, the injection means is removed from the capsule and the upper membrane is closed again due to its elasticity to prevent leakage.

[0041] The inventors have achieved particularly promising results when the biodegradable upper membrane of the present invention has a multilayer structure, for example, a structure comprising two or more or three or more layers.

[0042] For example, the inventors of the present invention have a biodegradable upper membrane consisting of two layers, for example, A first layer containing at least one PHA blended with one or more biopolymers, Excellent results were achieved when a second layer containing polybutylene succinate (PBS) was included.

[0043] The inventors have further successfully tested additional film structures. Figure 4 shows an example of such a film structure. Thus, the biodegradable top film comprising at least one polyhydroxyalkanoate (PHA) according to the present invention can be further adapted to allow for further functionalization, such as enabling back-printing, and / or to introduce further and / or improved barrier properties. Different layers of the top film may be co-extruded. Layers added to enable back-printing and improve barrier performance may be laminated. Coatings may be applied to avoid adhesion to seal heads and to allow for a wide temperature handling window.

[0044] Therefore, in the biodegradable upper membrane according to the present invention, the upper membrane is The PHA blend layer consists of a PBS layer and a transparent adhesive coating layer. The PHA blend layer consists of a PBS layer and a sulfurized paper + adhesive layer. The PHA blend layer consists of a PBS layer and a regenerated cellulose + adhesive layer. A metallized PHA blend layer, a PBS layer and a transparent adhesive coating layer, The metallized PHA blend layer consists of a PBS layer and a sulfurized paper + adhesive layer. A metallized PHA blend layer, a PBS layer and a regenerated cellulose + adhesive layer, A PHA blend layer, a PBS layer, a second PHA blend layer, and a transparent adhesive coating layer. The PHA blend layer consists of a PBS layer, a second PHA blend layer, and a sulfurized paper + adhesive layer. The PHA blend layer consists of a PBS layer, a second PHA blend layer, and a regenerated cellulose + adhesive layer. The PHA blend layer consists of a PBS layer, a metallized PHA blend layer, and a transparent adhesive coating layer. The PHA blend layer consists of a PBS layer, a metallized PHA blend layer, and a sulfurized paper + adhesive layer, or The PHA blend layer may include a PBS layer, a metallized PHA blend layer, and a regenerated cellulose + adhesive layer.

[0045] For example, in the biodegradable upper membrane according to the present invention, the upper membrane extends from the inside of the beverage capsule to the outside of the beverage capsule. The PHA blend layer consists of a PBS layer and a transparent adhesive coating layer. The PHA blend layer consists of a PBS layer and a sulfurized paper + adhesive layer. The PHA blend layer consists of a PBS layer and a regenerated cellulose + adhesive layer. A metallized PHA blend layer, a PBS layer and a transparent adhesive coating layer, The metallized PHA blend layer consists of a PBS layer and a sulfurized paper + adhesive layer. A metallized PHA blend layer, a PBS layer and a regenerated cellulose + adhesive layer, A PHA blend layer, a PBS layer, a second PHA blend layer, and a transparent adhesive coating layer. The PHA blend layer consists of a PBS layer, a second PHA blend layer, and a sulfurized paper + adhesive layer. The PHA blend layer consists of a PBS layer, a second PHA blend layer, and a regenerated cellulose + adhesive layer. The PHA blend layer consists of a PBS layer, a metallized PHA blend layer, and a transparent adhesive coating layer. The PHA blend layer consists of a PBS layer, a metallized PHA blend layer, and a sulfurized paper + adhesive layer, or The PHA blend layer may include a PBS layer, a metallized PHA blend layer, and a regenerated cellulose + adhesive layer.

[0046] While we do not wish to be bound by theory, the inventors currently believe that the PBS layer of the biodegradable supermembrane according to the present invention contributes to the supermembrane's ability to withstand high pressure by allowing some elongation without being destroyed. The use of PHA and / or PHA blends appears to make it possible to properly perforate the biodegradable supermembrane according to the present invention while avoiding leakage at high pressure and temperature.

[0047] Specifically, at least a portion of the upper membrane adapted to be punctured for fluid injection, Tensile strength of more than 1 MPa, preferably more than 5 MPa, more preferably more than 10 MPa, and It can exhibit elongation at break of more than 100%, preferably more than 500%.

[0048] Such an upper membrane is closed again to prevent leakage after the fluid injection means is removed from it.

[0049] In one preferred embodiment, the upper film is a multilayer film, and this multilayer film comprises at least, A first layer film consisting of PHA blended with one or more biopolymers, The invention comprises a second layer film consisting of at least one polybutylene succinate (PBS).

[0050] Typically, a multilayer film includes a lower layer film, which is configured to seal onto at least a portion of the upper surface of the circumferential flange of the capsule body, and preferably, this lower layer film is different from a second layer film of at least one polybutylene succinate (PBS). Therefore, it is preferable that the PBS-containing layer does not come into contact with the beverage during preparation.

[0051] A layer containing at least one PHA blended with one or more biopolymers may be, for example, a sealant layer. The biopolymers may be selected from the group consisting of ethylene vinyl alcohol (EVOH), polyvinyl alcohol (PVOH), ethylene vinyl acetate (EVA), polysulfone, polyethersulfone, cellulose, cellulose acetate, cellulose butyrate, cellulose triacetate, PLA, PBS, or combinations thereof.

[0052] The outer layer may contain or consist of polybutylene succinate (PBS). PBS may be, for example, bio-based polybutylene succinate (bioPBS) produced from the polymerization of bio-based succinic acid and 1,4-butanediol. A printed layer and / or a water vapor permeable (WVT) barrier layer may be applied on the outer layer. The printed layer may be a paper-based layer and may be applied by lamination. The WVT barrier layer may be applied, for example, by metallization.

[0053] The present inventors have obtained very good results using a biodegradable superfilm according to the present invention having a thickness of less than 150 μm, for example, in the range of about 50 to 150 μm, having a sealant layer having a thickness of less than 90 μm, for example, in the range of about 30 to 90 μm, and / or an outer layer having a thickness of less than 60 μm, for example, in the range of about 20 to 60 μm.

[0054] Furthermore, for example, the inventors have demonstrated that the biodegradable upper membrane of the present invention has three layers, for example, A lower layer containing at least one PHA blended with one or more biopolymers, The inner layer contains polybutylene succinate (PBS), Upper layer and Excellent results were obtained when [this condition] was present.

[0055] The lower layer refers to the layer attached to the flange of the main capsule and in contact with the beverage being prepared, while the upper layer refers to the layer facing the outside of the capsule.

[0056] The lower layer, which contains at least one PHA blended with one or more biopolymers, may be, for example, a sealant layer. The biopolymers may be selected from the group consisting of ethylene vinyl alcohol (EVOH), polyvinyl alcohol (PVOH), ethylene vinyl acetate (EVA), polysulfone, polyethersulfone, cellulose, cellulose acetate, cellulose butyrate, cellulose triacetate, PLA, PBS, or combinations thereof.

[0057] The inner layer may contain or consist of PBS or bio-PBS. An upper print layer and / or a water vapor permeable (WVT) barrier layer may be applied on the inner layer. The print layer may be a paper-based layer and may be applied by lamination. The WVT barrier layer may be applied, for example, by metallization.

[0058] The present inventors have obtained very good results using a biodegradable superfilm according to the present invention, which has three layers having a total thickness of less than 120 μm, for example, in the range of about 40 to 120 μm, and the superfilm has a sealant layer having a thickness of less than 90 μm, for example, in the range of about 30 to 90 μm, and / or an inner and / or outer layer having a thickness of less than 50 μm, for example, in the range of about 5 to 50 μm.

[0059] The biodegradable upper membrane according to the present invention, comprising two or three layers, may be co-extruded.

[0060] Therefore, the biodegradable upper membrane according to the present invention can be manufactured by a process that includes the step of co-extruding a layer containing at least one PHA blended with one or more biopolymers and a layer containing PBS.

[0061] This method may also include the step of laminating a printing layer and a WVT barrier layer on top of a layer containing PBS.

[0062] The inventors have achieved an excellent biodegradation rate for the biodegradable upper membrane according to the present invention. For example, the inventors were able to demonstrate that at least 90% by weight of the biodegradable upper membrane according to the present invention can be biodegraded in 22 days using the same thermal conditions as for PHA-specific strains and industrial compost.

[0063] Therefore, the biodegradable upper membrane according to the present invention may be compostable, for example, under industrial or household composting conditions.

[0064] In a second embodiment, a system of capsule and beverage preparation machines as described above is provided, the machine comprising a liquid injection hollow needle for injecting an extract into or into a chamber under pressure.

[0065] Preferably, the beverage preparation machine of this system is A capsule holder for receiving and holding capsules in a beverage preparation machine, A capsule holder receiving area for inserting a removable capsule holder and Includes, The liquid injection hollow needle and the inserted capsule holder are movable relative to each other so that the liquid injection hollow needle punctures the upper membrane of the capsule.

[0066] In the final embodiment, the use of the capsule described above in this system is provided.

[0067] In this application, the terms “upper” and “lower” are used to describe the relative positioning of the features of the present invention. These terms should be understood to refer to the normal orientation of the capsule when placed in a beverage preparation machine for producing a beverage, as shown in Figures 1, 2, 3A, and 3B.

[0068] Those skilled in the art will understand that all the features of the present invention disclosed herein can be freely combined. The features described for the products of the present invention can be combined. Furthermore, features described for different embodiments of the present invention may also be combined.

[0069] Although the present invention has been described by examples, it should be understood that modifications and alterations can be made without departing from the scope of the present invention as defined in the claims.

[0070] Furthermore, where known equivalents exist for a particular feature, such equivalents are incorporated as specifically referred to herein. Further advantages and features of the present invention are evident from the figures and non-limiting embodiments. [Brief explanation of the drawing]

[0071] Further features, advantages, and objectives of the present invention will become apparent to those skilled in the art upon reading the following detailed description of embodiments of the invention in conjunction with the accompanying drawings. Even if numbers are omitted from the drawings for clarity, corresponding features may still be present in the drawings. [Figure 1] This is a schematic cross-sectional view of the capsule according to the present invention. [Figure 2] This shows a system for a capsule and beverage preparation machine according to the present invention. [Figure 3A] Figures 1 and 2 show cross-sectional views of the capsule and capsule holder in two different operations. [Figure 3B] Figures 1 and 2 show cross-sectional views of the capsule and capsule holder in two different operations. [Figure 4] An example of the structure of the biodegradable upper membrane according to the present invention is shown.

[0072] [Modes for carrying out the invention] Figure 1 schematically shows capsule 1 used in the system of the present invention.

[0073] Capsule 1 comprises a capsule body 2 having one or more side walls 22 extending axially from the bottom to the top. The side walls extend toward an upper opening 23. At the upper opening 23, the body includes a circumferential flange 24 that extends radially outward from the side walls and continuously along the circumference of the opening. Typically, the flange 24 is connected to the capsule body by a connecting portion 243. For example, at the connecting portion 243, the side wall 22 may transition into the flange 24.

[0074] The flange 24 is typically formed integrally with one or more side walls 22. The flange comprises an upper surface 241 facing the top and a lower surface 242. The lower surface preferably includes or consists of a flat surface.

[0075] Generally, as shown in the perspective view of Figure 2, any cross-section of the main capsule is circular from bottom to top, and the flange is also circular.

[0076] The side wall defines a chamber 21 for containing soluble and / or extractable beverage ingredients.

[0077] This soluble beverage ingredient is a water-soluble powder ingredient and can be selected from the list of instant coffee powder, milk powder, cream powder, instant tea powder, cocoa powder, soup powder, fruit powder, or mixtures of such powders. The powder may be coagulated or sintered.

[0078] The beverage ingredients packaged in the box may be ingredients that can be extracted or steeped, such as roasted and ground coffee or tea leaves. In this embodiment, water is used to extract the beverage ingredients.

[0079] The capsule is fixed, sealed, or attached to at least a portion of the upper surface 241 of the circumferential flange and includes an upper membrane 3 that covers and closes the upper opening 23 accordingly.

[0080] The upper membrane is adapted to be punctured for liquid injection into the capsule, as shown in Figure 3B. Preferably, the upper membrane is perforable by an injection needle of a beverage preparation machine, and the injection needle is adapted to inject the extract under pressure into or into the chamber. Preferably, the puncture operation is performed in a single location by a water injection needle, as described in International Publication No. 2006 / 082064 or International Publication No. 2008 / 107281.

[0081] The term "upper membrane" should be understood as the membrane punctured by the machine's injection needle, in contrast to the "lower membrane" (described below), which is located on the opposite side of capsule 1.

[0082] The capsule comprises a lower membrane 4 that closes the bottom of the chamber 21. Thus, soluble and / or extractable beverage ingredients are sealed between the upper and lower membranes. The upper and lower membranes define the internal space of the ingredient chamber 22, which is a chamber configured to hold beverage ingredients for the preparation of the beverage.

[0083] In one embodiment, the feed wall 6 may extend through the internal cross-section of the chamber, defining a lower sub-chamber for the raw material and an upper distribution chamber for the liquid. This feed wall is provided with small holes for uniformly supplying the liquid onto the raw material.

[0084] The capsule includes an opening device 5 adapted to open the chamber by engaging with the lower membrane 4 under the influence of the rising liquid pressure in the chamber during the injection of the liquid. The opening device 5 may include a rigid plate 51 having opening elements 52 such as spikes, cones, or pyramidal shapes (optionally with truncated ends) on its surface oriented upward toward the lower membrane 4, which can form protrusions and recesses toward the lower membrane 4 facing the opening device. The opening device 5 is sometimes commonly referred to as a "pyramid plate." When liquid is injected into the chamber 4, the pressure rises, deforming the lower membrane 4 relative to the opening device 5 until the lower membrane is perforated, causing the beverage prepared in the capsule 1 to fall from the chamber 21 to below the opening device 5. The expression "engage" may mean, for example, that the opening device or the second membrane, or both, can move relative to each other to produce an opening.

[0085] Typically, the capsule body includes a lower beverage outlet 25 below the opening device 5. Preferably, the lower part of the capsule body extends below the opening means to hold the opening means and collect the beverage at the beverage outlet 25, distributing the beverage outside the capsule 1, for example, into a cup.

[0086] The upper membrane 3 is fixed to the flange 24 so that the extract injected into the chamber 21 increases the internal pressure to the pressure necessary to cause perforation of the lower membrane 4, which is deformed by the opening device 5. Thus, the upper membrane 3 is fixed to the flange so as not to detach until at least a specified pressure inside the chamber is achieved. This specified pressure may be at least 2 bar, preferably at least 3 bar or at least 6 bar. In this regard, this fixation prevents the capsule 1 from leaking through the interface between the flange and the upper membrane during beverage preparation.

[0087] Preferably, at least the capsule body 2 and the upper membrane 3 are made of compostable material, and more preferably, all elements of the capsule are made of compostable material and / or contain compostable material.

[0088] Typically, the upper film 3 is attached to the flange 24 by heat sealing, with or without the addition of sealant. In this way, a seal is formed between the upper film and the flange.

[0089] Figure 2 shows a system comprising the capsule 1 described above and a beverage preparation machine 10 configured to prepare a beverage from the capsule. The machine includes a capsule holder 11 that is removable from the machine, the capsule holder 11 having a receiving area 111 for introducing the body of the capsule, the flange 24 of the body being supported on the circumferential rim 112 of the holder. The capsule holder can then be inserted into the receiving area 13 of the machine to prepare the beverage.

[0090] This machine includes a capsule holder receiving area 13 for inserting a removable capsule holder into which a capsule holder can be inserted for preparing a beverage.

[0091] In addition, the machine includes, above the receiving area 13 for the capsule holder, a liquid injection device 12 having an injection means 121, more precisely, a hollow needle configured to penetrate the upper membrane 3 and inject water into the interior of the capsule. The injection device and the capsule holder are relatively movable to tighten around the circumferential annular flange of the capsule.

[0092] Next, the capsule holder 11 can be positioned at two locations within the receiving area 13, as shown in Figures 3A and 3B.

[0093] In Figure 3A, the capsule holder 11 has just been introduced into the receiving area 13, and in Figure 3B, the liquid injection plate 12 has been moved onto the inserted capsule holder, tightening the circumferential annular flange 24 of the capsule between the circumferential rim 112 of the holder and the injection plate 12.

[0094] Figure 4 shows the structure of the biodegradable upper membrane 3 that can be used in the capsule of Figure 1, and in the systems of Figures 2A, 2B, and 3.

[0095] All of these top films are multilayer films containing at least the following: A first layer film 31 of PHA blended with one or more biopolymers and A second layer film 32 consisting of at least one polybutylene succinate (PBS) and A third layer film 33 is provided that enables printing or the formation of a water vapor permeable barrier.

[0096] The first layer 31 is attached to the flange of the capsule body and preferably contains a sealant.

[0097] In some embodiments, the upper membrane 3 may include two first layer films 31, 31' of PHA blended with one or more biopolymers surrounding a second layer of at least one PBS.

[0098] Example 1: Extraction of coffee beverage A PHA biodegradable upper membrane according to the present invention, comprising a PHA blend layer, a PBS layer, and a second PHA blend layer, was prepared to a thickness of 150 μm and attached to a beverage capsule as shown in Figure 1. The capsule body was made of PHA. Coffee was filled into the beverage capsule under high pressure (5-9 bar) and extracted for a long time (25-30 seconds) through the upper membrane.

[0099] The samples were prepared in the same manner as commercially available coffee, including the use of a heat-sealing device to achieve heat sealing. The sealing head was protected with paper to prevent the top membrane from sticking.

[0100] No leaks were observed, even while preparing the beverage at the longest extraction time and highest pressure.

[0101] Example 2: Resistance test against rupture Since coffee extraction involves applying pressures exceeding 10 bar, we conducted burst resistance tests to check at what pressure the upper membrane detaches from the capsule flange.

[0102] The procedure for such measurement includes the following steps: a) placing the capsule to be tested inside the bell under airtight conditions; b) introducing compressed air (6 bar) into the bell through a hole in the bottom of the capsule and measuring the pressure inside the bell, wherein the capsule to be tested may be empty (without an opening means and a lower membrane), or, if there is an opening means and a lower membrane, the air introduced through the hole in the bottom will easily penetrate the lower membrane or wall, and in either case the result regarding the rupture resistance of the upper membrane will be the same; and c) waiting for the upper membrane to rupture and measuring the corresponding pressure.

[0103] These results showed that a capsule like the one defined in Example 1, having a 150 μm top membrane, could withstand 10 to 11 bar, while an equivalent capsule with a 120 μm top membrane could withstand 7 to 9 bar.

Claims

1. A capsule (1) for use in a beverage preparation machine, wherein the capsule contains a soluble and / or extractable beverage raw material, and the capsule Capsule body (2), The chamber (20) is defined, and a side wall (21) extends axially between the upper opening (23) and the lower outlet (25), A capsule body (2) comprises a circumferential annular flange (24) projecting radially outward from the upper opening, the circumferential annular flange (24) having an upper surface (241) on the opposite side of the chamber relative to the upper opening (23), and a lower surface (242) on the opposite side, An upper membrane (3) attached to at least a portion of the upper surface (241) of the circumferential annular flange, the upper membrane (3) providing a portion that closes the upper opening (23) and is adapted to be punctured for injecting liquid into the capsule, The lower membrane (4) is provided inside the chamber (20) so as to define the raw material chamber (22) between the upper membrane (3) and the lower membrane, and the lower membrane (4) contains the beverage raw materials, The raw material chamber (22) is provided with an opening device (5) located inside the chamber for opening the capsule by the relative engagement of the opening device and the lower membrane (4) under the influence of the pressure increase of the liquid injected into the chamber, The upper membrane (3) is biodegradable, The upper film (3) is a multilayer film, and the multilayer film is at least A second layer film (32) consisting of at least one polybutylene succinate (PBS), The second layer film (32) comprises two first layer films (31, 31') of polyhydroxyalkanoate (PHA) blended with one or more biopolymers, surrounding both sides of the second layer film (32), Capsule (1), wherein the upper membrane has a material thickness in the range of 120 to 150 μm.

2. The capsule according to claim 1, wherein the PHA is selected from the group consisting of P(3HB-co-3HV), PHB copolymer, P(3HB-co-3HHx), P(3HB-co-4HB), P(3HB), P(3HB-co-3HV), P(3HB-co-3HO), P(3HB-co-3Hod), or a combination thereof.

3. The capsule according to claim 1 or 2, wherein the first layer film (31) is a sealant layer of the upper film, and the first layer film (31) contains at least 30% by weight of PHA.

4. At least a portion of the upper membrane, which is adapted to be punctured for fluid injection, Tensile strength exceeding 1 MPa, and It shows elongation at the break of more than 100%. A capsule according to any one of claims 1 to 3.

5. The capsule according to any one of claims 1 to 4, wherein the capsule body (2) is made from a biodegradable material.

6. The capsule according to claim 5, wherein the biodegradable material of the capsule body (2) is polylactic acid (PLA), polyhydroxyalkanoate (PHA), polybutylene succinate (PBS), polybutylene succinate adipate (PBSA), or polybutylene adipate terephthalate (PBAT).

7. A system comprising a capsule and a beverage preparation machine (10) according to any one of claims 1 to 6, wherein the beverage preparation machine is equipped with a liquid injection hollow needle for injecting an extract into or into the chamber under pressure.

8. The beverage preparation machine (10) A capsule holder (11) for receiving and holding the capsule (1) within the beverage preparation machine, It comprises a capsule holder receiving area for inserting the removable capsule holder (11), The liquid injection hollow needle and the inserted capsule holder are movable relative to each other so that the liquid injection hollow needle punctures the upper membrane of the capsule. The system according to claim 7.

9. Use of the capsule according to any one of claims 1 to 6 in the system according to claim 8.

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