Capsule for producing beverage

Abstract

The invention relates to a capsule for use in a beverage preparation machine, said capsule containing soluble and / or extractable beverage ingredients, said capsule comprising:-a capsule body (2) defining a chamber (21),-a top membrane (3) closing a top opening and adapted to be pierced to inject a liquid into the capsule, and-a bottom membrane (4) arranged inside the chamber (21) so as to define a dosing chamber between the top membrane (3) and said bottom membrane, and-an opening device (5), and an opening device (5) provided inside the chamber and adapted to open the chamber during injection of the liquid by relative engagement of the opening device with the bottom membrane (4) under the action of an increase in liquid pressure in the dispensing chamber, where the opening device (5) is made of a biodegradable material, and the biodegradable material is a polymer composition comprising:-at least one polymer selected from the group consisting of a polyhydroxyalkanoate (PHA),-at least one or more nucleating agents,-at least one or more mineral fillers.

Description

Technical Field

[0001] The present invention relates to a capsule for use in a beverage preparation machine. Background Art

[0002] Single-serve beverage capsules are known in the art. These capsules are typically used with beverage preparation machines for dispensing beverages such as coffee or tea on demand.

[0003] For this purpose, a beverage capsule having a capsule body encapsulating the beverage ingredients is usually inserted into a capsule receiving part of a beverage preparation machine. The capsule receiving part is closed and the preparation of the beverage begins. In the capsule receiving part, the top membrane of the capsule is pierced with a needle and a fluid, usually water, is injected into the capsule to interact with the beverage ingredients inside the capsule to produce the desired beverage. The fluid fills the capsule, causing the pressure inside the capsule to increase. When a sufficient amount of fluid fills the capsule, a self-opening mechanism in the capsule is actuated to open the bottom membrane of the capsule to release the prepared beverage when the extraction of the beverage ingredients is completed. An example of the working principle of this type of container is described in patent EP 1472156.

[0004] In the prior art, such beverage containers are usually made of plastic. Considering that the containers are designed for single use only, their disposal must be managed, as reusing and recycling the used materials can be challenging. Therefore, attempts have been made to replace these materials with alternatives such as cellulose or bioplastics to overcome the problems of disposal and / or recycling of containers after use. However, it should be taken into account that these alternative materials do not have the same material properties and advantages as ordinary plastic materials.

[0005] In particular, considering the method described in patent EP 1472156 and in Figure 1 The capsule schematically shown in Figure 1, a capsule of this type comprises:

[0006] a capsule body 2 defining a chamber 21 with a top opening 23 closed by a top membrane 3 adapted to be pierced to inject liquid into the capsule, and

[0007] a bottom membrane 4 arranged inside the chamber so as to define a dosing chamber between the top membrane 3 and the bottom membrane 4, and

[0008] - opening means 5, arranged inside the capsule body and below the bottom membrane and adapted to open the ingredient chamber by relative engagement of said opening means with the bottom membrane under the effect of the increased liquid pressure in the chamber during the injection of liquid.

[0009] If the opening means 5 of a capsule exhibiting such a configuration is made of bioplastic, several disadvantages may be observed.

[0010] One disadvantage is that, under conditions of increased temperature and pressure, the properties of objects made of bioplastics may change. In the case of the above-mentioned capsules, this property change is a serious problem for an opening device made of bioplastics, because when hot water is introduced into the chamber and until the pressure increases and the bottom membrane is pushed towards the opening device, the opening device deforms, with the risk of breaking and / or not recovering its original shape after the bottom membrane tears and the pressure decreases. As a result, beverage ingredients may be dispensed from the ingredient chamber into the drinking cup, such as roasted and ground coffee particles or undissolved soluble powders, or a portion of the beverage is not prepared correctly. The beverage preparation is unacceptable to the consumer.

[0011] Another disadvantage is that the opening device presents a certain thickness in order to provide resistance to the pressure rising in the capsule during beverage preparation. Therefore, when this thick piece of material is made of bioplastic, its disintegration as a home compostable object becomes relatively long.

[0012] The purpose of the present invention is to solve the above-mentioned problems. Summary of the invention

[0013] In a first aspect of the invention there is provided a capsule for use in a beverage preparation machine, the capsule containing a soluble and / or extractable beverage ingredient and comprising:

[0014] - a capsule body defining a chamber, and

[0015] - a top membrane closing the top opening and adapted to be pierced to inject liquid into the capsule, and

[0016] - a bottom membrane arranged inside the chamber so as to define a dosing chamber between the top membrane and said bottom membrane, and

[0017] - an opening device arranged inside the chamber and adapted to open the chamber by relative engagement of the opening device with the bottom membrane under the effect of the increase in liquid pressure in the dosing chamber during the injection of the liquid, and wherein the opening device is a moulding made of a biodegradable material, and the biodegradable material is a polymer composition comprising:

[0018] - at least one polymer selected from the group consisting of polyhydroxyalkanoates (PHA),

[0019] - at least one or more nucleating agents,

[0020] - At least one or more mineral fillers.

[0021] The capsule comprises a capsule body defining a chamber for beverage ingredients, a top membrane closing the chamber, a bottom membrane arranged inside the chamber and opening means adapted to open said bottom membrane.

[0022] The capsule body generally comprises:

[0023] - a side wall defining the chamber and extending axially between the top opening, and

[0024] - a circumferential flange protruding radially outwards from the top opening, said flange comprising an upper surface opposite the cavity relative to the opening and an opposite lower surface.

[0025] Typically, the bottom of the capsule body comprises an outlet through which the beverage can be dispensed.

[0026] Typically, the top diaphragm is attached to the upper surface of the flange of the body.

[0027] The capsule contains a beverage ingredient, which may be a soluble or extractable beverage ingredient. The ingredient is held between a top membrane and a bottom membrane.

[0028] The opening device is positioned inside the body but outside the dosing chamber.Therefore, the opening device is positioned below the bottom membrane.

[0029] Typically, the opening device comprises a plate, and the plate comprises opening elements rising from the upper surface of the plate and thus in the direction of the bottom membrane. These opening elements are designed to pierce, tear, puncture the bottom membrane under the effect of the increased liquid pressure in the dosing chamber during the injection of the liquid.

[0030] These raised opening elements may be conical or pyramidal spikes (optionally truncated at their ends) turned upwards towards the bottom membrane, which may form projections and depressions against the bottom membrane facing the opening device.

[0031] Preferably, the opening element presents a sharp pointed end.

[0032] Preferably, the plate of the opening device comprises a beverage discharge aperture extending from an upper surface of the plate to a lower surface of the plate, and said aperture is positioned between the raised opening elements.

[0033] In the prior art, such opening devices are mouldings of plastic, such as polypropylene.

[0034] In this embodiment, the opening device is a molded part of a biodegradable material. The biodegradable material is a polymer composition comprising:

[0035] - at least one polymer selected from the group consisting of polyhydroxyalkanoates (PHA),

[0036] - at least one or more nucleating agents,

[0037] - At least one or more mineral fillers.

[0038] The opening device is manufactured from the polymer composition by molding.

[0039] Typically, the opening device is integrally made from this polymer composition.

[0040] Typically, the polymer composition comprises at least one polyhydroxyalkanoate comprising repeating units of formula (I):

[0041] -O-CHR i -(CH2) n -CO-

[0042] in:

[0043] -Ri is selected from -H, C1-C 12 Alkyl, CC 16 Cycloalkyl, C2-C 12 alkenyl, which is optionally substituted by at least one group selected from halogen (F, CI, Br), -CN, -OH,

[0044] -COOH, -OR, -COOR (wherein R = C1-C4 alkyl, benzyl),

[0045] - n is zero or an integer from 1 to 6, preferably 1 or 2.

[0046] Preferably, the polymer composition comprises at least one polyhydroxyalkanoate wherein Ri is methyl or ethyl and n is 1 or 2.

[0047] Preferred repeating units of formula (I) may be those derived from:

[0048] -3-Hydroxybutyrate,

[0049] -3-Hydroxyvalerate,

[0050] -3-Hydroxyhexanoate,

[0051] -3-Hydroxyoctanoate,

[0052] -3-Hydroxydodecanoate,

[0053] -3-Hydroxyundecene-10-enoate,

[0054] -4-Hydroxyvalerate,

[0055] or a mixture thereof.

[0056] Particularly preferred polyhydroxyalkanoates are:

[0057] - Poly-3-hydroxybutyrate (PHB),

[0058] - Poly-3-hydroxyvalerate (PHV),

[0059] - poly-3-hydroxyhexanoate (PHH),

[0060] - Poly-3-hydroxyoctanoate (PHO),

[0061] - poly-3-hydroxydodecanoate (PHDd),

[0062] - poly-3-hydroxyundecene-10-enoate (PHU),

[0063] And their copolymers:

[0064] - poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV),

[0065] - poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH),

[0066] - poly(3-hydroxybutyrate-co-4-hydroxybutyrate),

[0067] - poly(3-hydroxyoctanoate-co-3-hydroxyundecene-10-enoate) (PHOU),

[0068] - poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxyvalerate) (PHBW),

[0069] or a mixture thereof.

[0070] In one embodiment, the polyhydroxyalkanoate may be a copolymer or terpolymer comprising repeating units of formula (I) in combination with at least one repeating unit derived from a comonomer capable of copolymerizing with the hydroxyalkanoate.

[0071] These comonomers may be lactones and / or lactams.

[0072] In this embodiment, typically, the recurring unit of formula (I) is present in an amount equal to at least 10 mol % relative to the total number of moles of recurring units.

[0073] Preferably, the polyhydroxyalkanoate has a 4 g / mol to 10 6 The weight average molecular weight (M) is in the range of g / mol.

[0074] Generally, the polymer composition comprises at least one plasticizer selected from the group consisting of:

[0075] -poly(ethylene glycol) (PEG),

[0076] - acetyl-tri-n-butyl citrate (ATBC),

[0077] -isosorbide diacetate (ISE),

[0078] - Sorbitol,

[0079] -glycerin,

[0080] - acetylated monoglycerides,

[0081] - epoxidized soybean oil (ESBO),

[0082] -Triethyl citrate (TEC),

[0083] - tri(ethylene glycol)bis(2-ethylhexanoate) (TEG-EH),

[0084] - tributyl citrate (TBC),

[0085] -1,3,2,4-Dibenzylidene sorbitol,

[0086] -1,3-p-methylbenzylidene-2,4-benzylidene sorbitol,

[0087] -bis(stearylureide)hexane,

[0088] -1,3,2,4-di(p-methylbenzylidene)sorbitol,

[0089] -1,3,2,4-Dibenzylidene sorbitol,

[0090] and mixtures thereof.

[0091] The polymer composition comprises at least one nucleating agent which can be selected from the group consisting of boron nitride, talc, hydroxyapatite, zinc stearate, nanocrystalline cellulose, montmorillonite nanoclay, single-walled carbon nanotubes, wollastonite, multi-walled carbon nanotubes, cyanuric acid, fatty acids, fatty acid esters, fatty acid amines, fatty acid metal salts, pentaerythritol, dipentaerythritol, urea derivatives, sorbitol-based compounds, sodium benzoate, and mixtures thereof.

[0092] Preferably, the polymer composition comprises at least one nucleating agent in an amount of at least 0.1 wt. %, preferably at most 5 wt. %.

[0093] The polymer composition comprises at least one mineral filler which may be selected from the group consisting of talc, wollastonite, mica, silica, calcium carbonate, kaolin, nanoclay.

[0094] Preferably, the polymer composition comprises at least one mineral filler in an amount of at least 1 wt.-%, preferably at most 50 wt.-%.

[0095] Preferably, the polymer composition comprises wollastonite, talc or nanoclay as mineral filler, even more preferably in an amount between 5 and 40 wt.%.

[0096] It was observed that the presence of inorganic fillers inside the polymer composition of the opening device comprising a polymer selected from the group consisting of polyhydroxyalkanoates (PHA) accelerates the disintegration of the opening compared to terpolymer compositions without these mineral fillers.

[0097] The polymer composition may comprise at least one functional additive selected from the group consisting of:

[0098] -pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate),

[0099] -3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid octadecyl ester,

[0100] - tris(2,4-di-tert-butylphenyl) phosphite,

[0101] -1,3,5-trimethyl-2,4,6-tris-(3,5-di-tert-butyl-4-hydroxybenzyl)benzene,

[0102] -2,4-bis[(octylthio)methyl]-o-cresol,

[0103] -2,2t-dihydroxy-4,4t-dimethoxy-benzophenone,

[0104] - bis(oxyethylene)bis-(3-(5-tert-butyl-4-hydroxy-m-tolyl)vinyl propionate,

[0105] -[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid octadecyl ester

[0106] di-tert-butyl-4-hydroxyfeyl)propionate),

[0107] -2t,3-bis[[3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionyl]]propionylhydrazide,

[0108] -beeswax,

[0109] -Carnauba wax,

[0110] - Candelilla wax,

[0111] - Rhus wax (Japan wax),

[0112] -Berry wax,

[0113] -paraffin,

[0114] - polysiloxanes and their derivatives,

[0115] - magnesium hydroxide,

[0116] -Calcium stearate

[0117] and mixtures thereof.

[0118] These functional additives can be used to improve processability, compatibility between materials and / or accelerate biodegradation.

[0119] The polymer composition may comprise at least one viscosity modifier and / or compatibilizer selected from the group consisting of:

[0120] - dicumyl peroxide (DCP),

[0121] - tert-butyl peroxybenzoate (TBPB),

[0122] - hexamethylene diisocyanate (HMDI),

[0123] -Multifunctional styrene-co-glycidyl methacrylate oligomer

[0124] - triglycidyl isocyanurate (TGIC),

[0125] -Benzoyl peroxide (BPO),

[0126] - diphenylmethane diisocyanate (MDI).

[0127] Preferably, the polymer composition may comprise fibers, such as fibers selected from the group consisting of flax, corn, rice husk, hemp, bamboo, sisal, kenaf, and mixtures thereof.

[0128] The advantage of integrating fibers into the polymer composition of the opening device is that the disintegration of the opening portion is accelerated compared to a pure PHA-based composition without these fibers. This is particularly useful for the opening device, which may be a thick piece of material and therefore requires more time to disintegrate than the rest of the capsule.

[0129] Preferably, the polymer composition comprises such fibers in an amount between 5 and 40 wt. %.

[0130] Typically, the opening device comprises a plate comprising an opening element rising from the upper surface of the plate, the opening element being designed to pierce, tear, rupture the bottom membrane under the effect of the increased liquid pressure in the dosing chamber during injection of said liquid.

[0131] Preferably, the opening element presents a sharp pointed end, in particular when the bottom membrane is made of a material exhibiting a certain elasticity, which may be the case when the bottom membrane is made of a biodegradable material.

[0132] This may be the case when the bottom membrane is a laminated multilayer material which successively comprises:

[0133] - vegetable parchment layer, and

[0134] - an adhesive layer, and

[0135] - a layer of nonwoven material comprising fibres, wherein said fibres are biodegradable fibres. In case of such a bottom bottom membrane, usually the vegetable parchment support faces the opening means inside the capsule.

[0136] In one embodiment, it is preferred that the plate of the opening device comprises a beverage discharge hole extending from the upper surface of the plate to the lower surface of the plate, and the hole is positioned between the raised opening elements. This is particularly preferred when the bottom membrane is a laminated multilayer material such as described above.

[0137] Preferably, the capsule body is made of a biodegradable or decomposable material, such as paper-based starch, polycaprolactone (PCL), polylactic acid (PLA), polyhydroxyalkanoate (PHA), polybutylene succinate (PBS), polybutylene succinate adipate (PBSA) and / or polybutylene adipate terephthalate (PBAT), polyglycolic acid (PGA) or a mixture thereof.

[0138] Preferably, the top film is made of a biodegradable or decomposable material such as paper-based starch, polycaprolactone (PCL), polylactic acid (PLA), polyhydroxyalkanoate (PHA), polybutylene succinate (PBS), polybutylene succinate adipate (PBSA) and / or polybutylene adipate terephthalate (PBAT), polyglycolic acid (PGA) or mixtures thereof.

[0139] The capsule may include a distributor wall extending through the inner cross-section of the chamber to define a lower sub-chamber for the ingredients and an upper distribution chamber for the liquid. Such a distributor wall includes small holes to evenly distribute the liquid on the ingredients.

[0140] Such dispensers may be compostable films made of cellophane and starch, or polycaprolactone (PCL), polylactic acid (PLA), polyhydroxyalkanoate (PHA), polybutylene succinate (PBS), polybutylene succinate adipate (PBSA) and / or polybutylene adipate terephthalate (PBAT), polyglycolic acid (PGA), or mixtures thereof.

[0141] Typically, the capsule is produced by producing the capsule body and the opening device separately and assembling them in a further step.

[0142] In a particular embodiment, the capsule body may comprise a bottom wall integrally formed with the opening means.

[0143] Therefore, in this embodiment, the opening device is integrally formed with the capsule body. The capsule body is molded from the same biodegradable polymer composition as the opening device.

[0144] In this application, the technical requirements and procedures for determining the biodegradability and compostability of materials are determined according to international standards (such as EU 13432 or US ASTM D6400). For example, in order for a material to be considered "(industrially) degradable", one of the tests requires that at least 90% of the material must be biodegraded within 6 months under controlled conditions. There are similar testing schemes for home degradability certification.

[0145] Thus, the entire capsule system can be disposed of in a compost heap after use, in order to provide nutrients to the soil after the material has fully biodegraded.

[0146] The above aspects of the present invention may be combined in any suitable combination. In addition, various features herein may be combined with one or more of the above aspects to provide combinations other than those specifically illustrated and described. Additional objects and advantageous features of the present invention will be apparent from the claims, specific embodiments, and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0147] Specific embodiments of the present invention will now be further described by way of example with reference to the following drawings, in which:

[0148] - Figure 1 shows a schematic cross section of a capsule according to the invention,

[0149] - Figure 2 is a graph showing the strain of different polymer materials. DETAILED DESCRIPTION

[0150] Figure 1 A capsule 1 according to the invention is schematically shown.

[0151] The capsule 1 comprises a capsule body 2 having one or more side walls 21 extending axially from the bottom towards the top. The side walls extend towards a top opening 23. At the top opening 23, the body comprises a circumferential flange 24 extending radially outwards from the side walls.

[0152] Generally, as shown in the perspective view of FIG. 2 , any transverse cross-section of the main body capsule is circular from bottom to top, and the flange is also circular.

[0153] The side wall defines a chamber 22 for containing soluble and / or extractable beverage ingredients.

[0154] Such a soluble beverage ingredient is a water soluble powdered ingredient and may be selected from the following list: instant coffee powder, milk powder, cream powder, instant tea powder, cocoa powder, soup powder, fruit powder or a mixture of said powders. The powder may be agglomerated or fired.

[0155] This beverage ingredient packaged in the bag can also be an ingredient that can be extracted or infused, such as roasted and ground coffee, or tea leaves. In the embodiment described, the beverage ingredient is subjected to water extraction.

[0156] The capsule comprises a top membrane 3 which is fixed, sealed or attached to at least a portion of the upper surface of the circumferential flange and thus covers and closes the top opening 23 .

[0157] Such top membrane is adapted to be punctured to inject liquid into the capsule. Preferably, the top membrane is puncturable by an injection needle of a beverage preparation machine, the injection needle being adapted to inject extraction liquid under pressure into or inside the chamber. Preferably, the puncturing operation is performed at a single location by a water injection needle such as described in WO2006 / 082064 or WO2008 / 107281.

[0158] The term "top membrane" is to be understood as the membrane pierced by the injection needle of the machine, as opposed to the "bottom membrane" (such as described below) which is to be understood as the membrane located on the opposite side of the capsule 1 .

[0159] The capsule comprises a bottom membrane 4 closing the bottom of a chamber 22. Thus, soluble and / or extractable beverage ingredients are encapsulated between the top and bottom membranes. The top and bottom membranes define an interior space of a chamber (ingredient chamber 22) configured to hold beverage ingredients for preparing a beverage.

[0160] In one embodiment, a distributor wall 6 may extend through the inner cross section of the chamber, defining a lower sub-chamber for the ingredients and an upper distribution chamber for the liquid. Such a distributor wall comprises small holes to distribute the liquid evenly on the ingredients.

[0161] The capsule comprises an opening device 5 adapted to open the chamber by relative engagement with the bottom membrane 4 under the effect of the increase in liquid pressure in the chamber during injection of said liquid. The opening device 5 may comprise a rigid plate 51 comprising, on its surface turned upwards towards the bottom membrane 4, an opening element 52, such as a spike, a cone or a pyramidal shape (optionally truncated at its ends), which may form protrusions and depressions against the bottom membrane 4 facing the opening device. The opening device 5 may generally be referred to as a "pyramidal plate".

[0162] Apertures 53 may be provided in the plate 51 to distribute the beverage produced in the ingredient chamber 22 to the beverage outlet 25 .

[0163] After the liquid is injected inside the chamber 4, the pressure builds up, which deforms the bottom membrane 4 against the opening means 5 until it is pierced, thereby creating a passage for the beverage prepared inside the capsule 1, in turn under the chamber 21 and the opening means 5. The expression "engagement" may mean, for example, that the opening means or the second membrane, or alternatively both, are movable relative to each other to achieve the opening.

[0164] Typically, the capsule body comprises a bottom beverage outlet 25 located below the opening means 5. The bottom of the capsule body preferably extends below the opening means to accommodate said opening means and collect the beverage to this beverage outlet 25 which dispenses the beverage outside the capsule 1, e.g. into a cup.

[0165] The top membrane 3 is fixed to the flange 24 in such a way that the extraction liquid injected into the chamber 21 increases the internal pressure to the pressure necessary to obtain the piercing of the deformed bottom membrane 4 by the opening means 5. The top membrane 3 is thus fixed to the flange in such a way that it does not detach at least before a defined pressure is reached inside the chamber. The defined pressure may be at least 2 bar, preferably at least 3 bar or at least 6 bar. The fixing effect thus makes it impossible for the capsule 1 to leak via the interface between the flange and the top membrane during beverage preparation.

[0166] In the prior art, this type of capsule is made of plastic such as polypropylene. Such material presents the property of being adapted to the introduction of hot water at a temperature above 90°C and to raise the pressure inside the ingredient chamber 22 until the bottom membrane 4 is pierced. During the preparation of the beverage, the opening means 5 made of polypropylene deforms and bends slightly under the force exerted by the highest pressure, but recovers its original shape when the pressure decreases at the end of the beverage preparation. This therefore ensures the function of opening the bottom membrane and filtering the beverage.

[0167] When the opening device 5 is made of bioplastic, it has been observed that the opening device itself deforms under the temperature and pressure loads applied by the hot water inside the beverage ingredients chamber. The beverage cannot be prepared well because:

[0168] - The high pressure necessary to extract roasted and ground coffee or to mix soluble ingredients with water is not maintained throughout the beverage preparation process. Alternatively, it may occur that such deformation blocks the beverage flow and generates high pressures that rupture the capsule or break the opening device.

[0169] The resulting beverage did not exhibit the expected qualities.

[0170] - Some beverage ingredients (such as coffee cake or undissolved soluble ingredients) are not filtered and flow inside the drinking cup. Some broken parts of the deformed cone may also be released in the cup.

[0171] These disadvantages can be avoided by selecting as a biodegradable material a polymer composition as the opening device material, the polymer composition comprising:

[0172] - at least one polymer selected from the group consisting of polyhydroxyalkanoates (PHA), and

[0173] - at least one or more nucleating agents, and

[0174] - at least one or more mineral fillers,

[0175] In particular, the panels produced with such polymer compositions were subjected to a load of 1.4 MPa to reflect the pressure exerted by the pressurized water generated by the beverage machine pump and introduced inside the beverage capsule. The load was applied during 1.5 seconds and then released. It was observed that:

[0176] - these panels deform over time under load, and

[0177] - When the load is removed, the plates return to their original dimensions or deform only slightly.

[0178] The opening devices 5 made of these polymer compositions are used to manufacture Figure 1 Beverage capsules shown. The beverage ingredient is roasted and ground coffee. Coffee is prepared from different capsules using a beverage machine sold under the trademark Nescafé Dolce Gusto, from which coffee is suitably prepared.

[0179] Although the present invention has been described with reference to the above illustrated embodiments, it should be understood that the invention as claimed is not in any way limited to these illustrated embodiments.

[0180] Various changes and modifications may be made without departing from the scope of the invention as defined in the claims. In addition, where known equivalents exist for specific features, such equivalents shall be incorporated as if explicitly mentioned in this specification.

[0181] As used in this specification, the words "include", "comprises" and similar words should not be understood as having exclusive or exhaustive meanings. In other words, these words are intended to mean "including but not limited to".

[0182] List of references in the accompanying drawings :

[0183] Capsule 1

[0184] Capsule body 2

[0185] Chamber 20

[0186] Side wall 21

[0187] Batching chamber 22

[0188] Top opening 23

[0189] Flange 24

[0190] Bottom outlet 25

[0191] Top diaphragm 3

[0192] Bottom diaphragm 4

[0193] Open device 5

[0194] Rigid board 51

[0195] Open element 52

[0196] Hole 53

[0197] Distributor wall 6

Claims

1. A capsule (1) for use in a beverage preparation machine, said capsule containing a soluble and / or extractable beverage ingredient, The capsule comprises: - a capsule body (2), said capsule body defining a chamber (21), - a top membrane (3) closing the top opening and adapted to be pierced to inject liquid into the capsule, and - a bottom membrane (4) arranged inside the chamber (21) so as to define a dosing chamber between the top membrane (3) and the bottom membrane, and - an opening device (5) arranged inside the chamber and adapted to open the chamber by relative engagement of the opening device with the bottom membrane (4) under the effect of the increase in liquid pressure in the dosing chamber during the injection of the liquid, The opening device (5) is a molded part made of a biodegradable material, and the biodegradable material is a polymer composition, which comprises: - at least one polymer selected from the group consisting of polyhydroxyalkanoates (PHA), - at least one or more nucleating agents, - At least one or more mineral fillers.

2. The capsule according to claim 1, wherein the polymer composition comprises at least one polyhydroxyalkanoate having a repeating unit of formula (I): -O-CHR i -(CH2) n -CO- in: -Ri is selected from -H, C1-C 12 Alkyl, CC 16 Cycloalkyl, C 2-C1 2 alkenyl, which is optionally substituted by at least one group selected from the group consisting of halogen (F, Cl, Br), -CN, -OH, -COOH, -OR, -COOR (wherein R = C1-C4 alkyl, benzyl), - n is zero or an integer from 1 to 6, preferably 1 or 2. 3 . The capsule of claim 2 , wherein the polymer composition comprises at least one polyhydroxyalkanoate, wherein Ri is methyl or ethyl, and n is 1 or 2.

4. The capsule according to claim 2 or 3, wherein the polyhydroxyalkanoate is a copolymer or terpolymer comprising a repeating unit of formula (I) in combination with at least one repeating unit derived from a comonomer copolymerizable with hydroxyalkanoate.

5. The capsule according to any one of the preceding claims, wherein the polymer composition comprises at least one plasticizer selected from the group consisting of: -poly(ethylene glycol) (PEG), - acetyl-tri-n-butyl citrate (ATBC), -isosorbide diacetate (ISE), - Sorbitol, -glycerin, - acetylated monoglycerides, - epoxidized soybean oil (ESBO), -Triethyl citrate (TEC), - tri(ethylene glycol)bis(2-ethylhexanoate) (TEG-EH), - tributyl citrate (TBC), -1,3,2,4-Dibenzylidene sorbitol, -1,3-p-methylbenzylidene-2,4-benzylidene sorbitol, -bis(stearylurea)hexane, -1,3,2,4-di(p-methylbenzylidene)sorbitol, -1,3,2,4-Dibenzylidene sorbitol, and mixtures thereof.

6. The capsule according to any one of the preceding claims, wherein the polymer composition comprises at least one nucleating agent selected from the group consisting of boron nitride, talc, hydroxyapatite, zinc stearate, nanocrystalline cellulose, montmorillonite nanoclay, single-walled carbon nanotubes, multi-walled carbon nanotubes, cyanuric acid, fatty acids, fatty acid esters, fatty acid amines, fatty acid metal salts, pentaerythritol, dipentaerythritol, urea derivatives, sorbitol-based compounds, sodium benzoate, and mixtures thereof.

7. Capsule according to the preceding claim, wherein the polymer composition comprises a nucleating agent in an amount of at least 0.1 wt.-%, preferably at most 5 wt.-%.

8. Capsule according to any of the preceding claims, wherein the polymer composition comprises at least one mineral filler selected from the group consisting of talc, wollastonite, mica, silica, calcium carbonate, kaolin, nanoclay.

9. Capsule according to the preceding claim, wherein the polymer composition comprises mineral fillers in an amount of at least 5 wt.-%, preferably at most 40 wt.-%.

10. The capsule according to any one of the preceding claims, wherein the polymer composition comprises at least one functional additive selected from the group consisting of: -pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate), -3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid octadecyl ester, - tris(2,4-di-tert-butylphenyl) phosphite, -1,3,5-trimethyl-2,4,6-tris-(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, -2,4-bis[(octylthio)methyl]-o-cresol, -2,2t-dihydroxy-4,4t-dimethoxy-benzophenone, - bis(oxyethylene)bis-(3-(5-tert-butyl-4-hydroxy-m-tolyl)vinyl propionate, -[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid octadecyl ester, -2t,3-bis[[3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionyl]]propionylhydrazide, -beeswax, -Carnauba wax, - Candelilla wax, - Rhus wax (Japan wax), -Berry wax, -paraffin, - polysiloxanes and their derivatives, - magnesium hydroxide, -Calcium stearate and mixtures thereof.

11. The capsule according to any one of the preceding claims, wherein the polymer composition comprises at least one viscosity modifier and / or compatibilizer selected from the group consisting of: - dicumyl peroxide (DCP), - tert-butyl peroxybenzoate (TBPB), - hexamethylene diisocyanate (HMDI), -Multifunctional styrene-co-glycidyl methacrylate oligomer - triglycidyl isocyanurate (TGIC), -Benzoyl peroxide (BPO), - diphenylmethane diisocyanate (MDI).

12. Capsule according to any of the preceding claims, wherein the opening means (5) comprises a plate (51) comprising an opening element (52) rising from an upper surface (511) of the plate, the opening element (52) being designed to pierce, tear or rupture the bottom membrane (4) under the effect of the increased liquid pressure in the dosing chamber during the injection of the liquid.

13. Capsule according to the preceding claim, wherein said opening element (52) presents a sharp pointed end.

14. Capsule according to claim 12 or 13, wherein the plate (51) of the opening device (5) comprises a beverage discharge hole (53) extending from the upper surface (511) of the plate to the lower surface (512) of the plate, and the hole is positioned between the raised opening elements (52).

15. Capsule according to any one of the preceding claims, wherein the bottom membrane (4) is a laminated multilayer material comprising successively: - vegetable parchment layer, and - an adhesive layer, and - a nonwoven material layer comprising fibers, wherein the fibers are biodegradable fibers, and The plant parchment support faces the opening device (5).

16. Capsule according to any of the preceding claims, wherein the capsule body (2) comprises a bottom wall, and the bottom wall is made integrally with the opening device (5).

Images