Compostable capsules and manufacturing and use thereof

Abstract

To provide a compostable capsule for preparing beverages, especially hot beverages.SOLUTION: A compostable capsule for preparing beverages, particularly hot beverages, comprises: a core material of bulk substance selected from the group consisting of coffee powder, tea, cocoa, drinking chocolate, powdered milk, instant coffee, and dried soup, as well as combinations thereof; and a shell material containing the core material, the shell material being a compostable non-crosslinked polysaccharide, allowing the capsule to be compostable.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a compostable capsule containing ingredients suitable for the preparation of beverages, particularly hot beverages, and to its preparation and use.

[0002] The provision of luxury foods, such as coffee, in capsule form is well known, but the materials typically used as packaging, such as plastic or aluminum (see, for example, EP 2106375(A2)), have the disadvantage that they are not compostable.

[0003] DE 102014000187(B4) proposes coating compacts, for example for the production of coffee, with a coating consisting of a biodegradable layer, said layer being a polysaccharide or its derivative in combination with a polyol spacer and a bound cross-linking agent, i.e. a cross-linked polysaccharide. No specific examples of an embodiment are given.

[0004] EP 3115316 (B1) describes, for example, similar capsules for the production of coffee, whereby a cross-linked polysaccharide shell material is obtained without the use of a polyol spacer, and in particular calcium alginate is mentioned as the shell material.

[0005] In US Patent Application Publication No. 2013 / 0136843 A1 it is proposed to coat a core of coffee powder with a compressed coffee shell.

[0006] The above-mentioned prior art solutions are still not optimal with regard to providing compostable capsules for the preparation of hot beverages in the most economical, ecologically compatible and production-wise possible manner. Summary of the Invention [Problem to be solved by the invention]

[0007] The object of the present invention was to provide a compostable capsule for preparing beverages, in particular hot beverages, thereby overcoming the drawbacks of the prior art. [Means for solving the problem]

[0008] The problem is solved by the subject matter of the independent claims of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0009] More particularly, the present invention relates to a compostable capsule for preparing beverages, in particular hot beverages, comprising: - a bulk material core material selected in particular from the group consisting of coffee powder, tea, cocoa, drinking chocolate, milk powder, instant coffee and dry soup and combinations thereof; - An outer covering material that contains a core material, the outer covering material being a compostable uncrosslinked polysaccharide. The present invention relates to a compostable capsule comprising:

[0010] According to the present invention, "compostable" is understood to mean that the material is at least home compostable in accordance with the certification schemes NF T51-800:2015-11-14 (Plastics - Specification for plastics suitable for home composting) and AS5810:2010 (Biodegradable plastics - Biodegradable plastics suitable for home composting). This means biodegradation of at least 90% of the material within 12 months at a temperature of 25±5°C, with release of CO2, and fragmentation (disintegration) of at least 90% of the material within 6 months at a temperature of 25±5°C. Taste.

[0011] The capsules of the present invention can have various shapes. Such a variety of shapes is already known in the prior art for corresponding capsules in the relevant technical field. For example, the capsules can have the shape of an oval, a cylinder, a cone, a truncated cone, a rectangular parallelepiped, a cube, a coffee bean, or a sphere. Preferably, the capsules are spherical.

[0012] The capsules of the present invention have a core-shell structure, i.e., a core (core material) of one material is surrounded by a shell (shell material) of another material. The shell can be formed seamlessly if it is not constructed of several parts (e.g., hard capsules). However, the shell can also be formed of two or more parts. The shell can have a line of weakness that makes it easier to open the shell.

[0013] The capsule of the present invention may contain a compact as the core material. According to the present invention, a "compacted body" is understood to mean a core material compressed under pressure. Providing the capsule core material as a compact is advantageous when the core material is encapsulated by dipping, coating, or spraying with the encapsulation material of the present invention, so that the core material does not crumble during the encapsulation process. Therefore, the core material preferably has a strength of at least 5 N, preferably in the range of 5 to 50 N, and more preferably in the range of 5 to 20 N. This can be achieved by compressing the core material at a compression pressure of preferably 1 to 100 MPa, preferably in the range of 5 to 50 MPa. The resulting compact with a shell preferably has a strength of 10 to 300 N, preferably 50 to 250 N, and particularly preferably 75 to 225 N.

[0014] The compression pressure applied to produce the pellets depends on the characteristics of the core material, for example, in the case of coffee powder, the roast level and moisture content of the powder in the grind. In particular, in the case of coffee powder, it can be observed that powders with lower fat or oil content, such as decaffeinated coffee powder, require higher compression pressures to achieve a stable compact.

[0015] The strength of the compact is determined by clamping the compact between two plates and measuring the force required to crush the compact, a method also described in WO 2008 / 123775(A1), page 3.

[0016] According to the present invention, the core material is selected from the group consisting of coffee powder, tea, cocoa, drinking chocolate, milk powder, instant coffee and dry soup, and combinations thereof. Such core materials are known and do not need to be described in detail here. Solid and / or swellable materials have been shown to be advantageous over soluble materials because the material does not dissolve during beverage preparation and the capsule substantially retains its shape until beverage preparation is complete.

[0017] The outer covering material used in accordance with the present invention is a compostable uncrosslinked polysaccharide. Uncrosslinked polysaccharides are understood to be polysaccharides in which the polymer chains are not linked to one another or are linked to one another with crosslinking agents only to a degree of crosslinking of at most 5%, preferably at most 2%, particularly preferably at most 1%.

[0018] The linking of polymer chains is generally understood to mean their connection to one another using a crosslinker, which includes not only conventional crosslinking, which involves the formation of a covalent bond between the polymer chain and the crosslinker, but also coordinate bonds, in which only the polymer chain forms an ionic interaction via its functional groups with the crosslinker, for example a polyvalent metal cation (e.g. calcium ion).

[0019] The cross-linking of the polysaccharides used requires the addition of a reactive partner (cross-linking agent) for cross-linking. and / or by not applying the reaction conditions required for the crosslinking reaction (eg, the presence of a required catalyst, the temperature required for crosslinking).

[0020] The outer shell is preferably designed not to dissolve during beverage preparation, especially during the preparation of hot beverages, so that during extraction with water up to 100°C and extraction times up to 3 minutes, the shell retains a stable shape, allowing the capsule to be ejected or removed from the beverage preparation machine without difficulty after beverage preparation.

[0021] The compostable uncrosslinked polysaccharide of the outer packaging material may be selected from the group consisting of starch, modified starch, pectin, cellulose, carrageenan, algin(ates), especially sodium alginate, agar, pullulan, chitin, chitosan and combinations thereof.

[0022] Preferably, according to the present invention, the compostable uncrosslinked polysaccharide of the outer covering material is selected from the group consisting of carboxymethyl cellulose (CMC), microfibrillated cellulose (MFC), sodium alginate, pullulan and chitosan, and combinations thereof.

[0023] Carboxymethyl cellulose and microfibrillated cellulose have the following basic structure:

[0024] [ka]

[0025] where R=CHCOOH, H for carboxymethylcellulose and R=H for cellulose. n (i.e., the number of monomers linked together in the molecular chain) is typically about 10 4 ~10 6 The degree of substitution of the carboxymethyl cellulose (i.e., the proportion of hydroxy groups substituted with carboxymethyl groups) should preferably be in the range of 60 to 95%.

[0026] Carboxymethyl cellulose and microfibrillated cellulose are commercially available and their preparation is known.

[0027] Sodium alginate has the following structure:

[0028] [ka]

[0029] Sodium alginate is a polysaccharide consisting of two uronic acids, α-L-guluronic acid (GulUA) and β-D-mannuronic acid (ManUA), linked by 1,4-glycosidic bonds in alternating proportions to form a linear chain. It forms homopolymer regions in which mannuronic acid or guluronic acid exists as blocks. These blocks are called GG blocks or MM blocks.

[0030] Sodium alginate is commercially available and its preparation is well known. Pullulan has the following structure:

[0031] [ka]

[0032] Pullulan is a polysaccharide having the formula:

[0033] Chitosan has the following structure:

[0034] [ka]

[0035] The value of n is typically about 2000. Chitosan and its production are known. Chitosan is commercially available.

[0036] The compostable uncrosslinked polysaccharide packaging can contain additional additives to modify the properties of the packaging, such as plasticizers such as glycerol, sorbitol, polyethylene glycol (PEG), or combinations of these plasticizers. Cellulose and cellulose derivatives are also contemplated as additives, particularly useful for enhancing stability.

[0037] The production of the capsules of the present invention can be carried out in the usual way by coating a compressed body of the desired core material with the outer covering material in the usual way, in particular by dipping, coating or spraying.

[0038] Therefore, the present invention provides a method for producing a compostable capsule according to the above description, comprising the steps of: a) providing a core material selected from the group consisting of coffee powder, tea, cocoa, drinking chocolate, milk powder, instant coffee and dry soup, and combinations thereof; b) compressing the core material into a compact; c) providing a system, in particular an aqueous system, comprising a compostable uncrosslinked polysaccharide; d) applying a system, in particular an aqueous system, to the surface of the part to be pressed, in particular by immersion, coating or spraying; e) drying the coated pellets and is carried out under non-crosslinking conditions.

[0039] The compostable uncrosslinked polysaccharide may be selected from the group listed above. The compression of core material into pellet form is well known and has already been described above.

[0040] Providing a compostable uncrosslinked polysaccharide-containing system, particularly an aqueous system, can be carried out conventionally by mixing a solution, particularly an aqueous solution, with the corresponding polysaccharide. The mixing step can be aided or facilitated by conventional means, such as stirring, heating, adjusting the pH range to increase the solubility of the polysaccharide, for example by adding an acid or base, or a combination of such means.

[0041] In this context, systems are understood not only to be aqueous systems (i.e. systems that contain predominantly water as a solvent). Systems also include water and water-miscible solutions, e.g., low-chain (e.g., C 1~8It is also contemplated that a solvent mixture of ethanol, ethanol, or a physiologically acceptable alcohol, such as ethanol, may be used in place of water to form an aqueous system. It is also contemplated that a coffee extract, for example, from brewed coffee or from instant coffee, may be used as a solvent in place of water to form an aqueous system.

[0042] The system is thus provided in the form of a solution, in particular an aqueous solution, having a compostable uncrosslinked polysaccharide concentration of 0.1 w / w% to 30 w / w%, preferably 1 w / w% to 20 w / w%, more preferably 3 w / w% to 6 w / w%, relative to the total weight of the system.

[0043] According to the invention, the system is preferably provided in the form of a solution, in particular an aqueous solution, with a carboxymethylcellulose concentration of 1 w / w% to 10 w / w%, preferably 2 w / w% to 6 w / w%, particularly preferably 3 w / w% to 5 w / w%, relative to the total weight of the system.

[0044] According to the present invention, it is further preferred to provide the system in the form of a solution, in particular an aqueous solution, having a microfibrillated cellulose concentration of 0.1 w / w% to 5 w / w%, preferably 0.2 w / w% to 2 w / w%, more preferably 0.5 w / w% to 1.5 w / w%, relative to the total weight of the system.

[0045] According to the invention, it is further preferred to provide the system in the form of a solution, in particular an aqueous solution, having a sodium alginate concentration of 1 w / w% to 5 w / w%, preferably 1.2 w / w% to 2.5 w / w%, more preferably 1.5 w / w% to 2 w / w%, relative to the total weight of the system.

[0046] According to the present invention, it is further preferred to provide the system in the form of a solution, in particular an aqueous solution, having a pullulan concentration of 1 w / w% to 30 w / w%, preferably 5 w / w% to 30 w / w%, more preferably 15 w / w% to 20 w / w%, relative to the total weight of the system.

[0047] According to the invention, it is further preferred to provide the system in the form of a solution, in particular an aqueous solution, having a chitosan concentration of 1 w / w% to 20 w / w%, preferably 1 w / w% to 10 w / w%, particularly preferably 3 w / w% to 8 w / w%, relative to the total weight of the system.

[0048] According to one preferred embodiment, softened or demineralized water is used in the step of providing an aqueous system comprising compostable uncrosslinked polysaccharides.

[0049] The system can contain additional additives to modify the properties of the applied coating, such as plasticizers such as glycerol, sorbitol, polyethylene glycol (PEG), or combinations of these plasticizers. Such additives are typically added to the system in amounts of 0.1 to 8 wt. % based on the total weight of the system, preferably 0.2 to 3.6 wt. %, and more preferably 0.5 to 2 wt. %.

[0050] The systems thus provided can be applied to the surface of the part to be pressed in the usual manner, in particular by dipping, coating or spraying, which methods are well known.

[0051] According to the present invention, coating of the desired core material with the outer covering material is preferably carried out by immersing the compacted body in the above-described system. For example, the compacted body can be introduced into the system by a suitable suspension and remains there for the desired time, for example, 1 to 60 seconds, preferably 2 to 30 seconds, particularly preferably 3 to 10 seconds. Other methods of coating in the immersion bath are envisioned, including, for example, a fixed position in the immersion bath or a rotational movement through the immersion bath.

[0052] The compressed body, whose surface is surrounded (i.e., coated) with the sheath material, is then removed from the system.

[0053] According to a preferred embodiment of the present invention, the packaging material is composed of 1 to 20 layers, preferably 2 to 10 layers, more preferably 2 to 5 layers, and the layers may be composed of the same or different compostable uncrosslinked polysaccharides.

[0054] If it is desired to provide a sheathing comprising multiple layers, the step of coating the compacted body may be carried out repeatedly using the same or different systems to provide 1 to 20 layers, preferably 2 to 10 layers, more preferably 2 to 5 layers on the surface of the compacted body. The types of coating steps may be the same or different coating steps may be used.

[0055] After the last coating step and / or between one or more individual coating steps, the coated compact is subjected to a drying step. This drying step can be carried out conventionally. According to the invention, the drying step is preferably carried out in an air stream by convection and / or contact drying. Examples are tray drying with hot air and IR drying (drying by irradiation with IR radiation). The temperatures used here are usually in the range of 10°C to 40°C or less at standard pressure, preferably 15-25°C, usually below 50°C.

[0056] Both the coating and drying process steps usually take a time length of 2 to 20 minutes, preferably 5 to 10 minutes.

[0057] According to one embodiment of the present invention, if the coating is carried out in a known manner by spray coating in a fluidized bed process, the coating of the compacted body and subsequent drying can be carried out in one process step, the temperatures applied for which are usually in the range of 25 to 40°C.

[0058] The above-described method of the present invention is carried out under non-crosslinked conditions. As mentioned above, the outer casing of the capsules of the present invention consists of non-crosslinked polysaccharides, i.e. polysaccharides whose polymer chains are not linked to each other or are linked to each other only to a degree of crosslinking with a crosslinking agent, i.e. a maximum of 5%, preferably at most 2%, particularly preferably at most 1%.

[0059] The linking of polymer chains is generally understood to mean their connection to one another using a crosslinker, which includes not only conventional crosslinking, which involves the formation of a covalent bond between the polymer chain and the crosslinker, but also coordinate bonds, in which only the polymer chain forms an ionic interaction via its functional groups with the crosslinker, for example a polyvalent metal cation (e.g. calcium ion).

[0060] Cross-linking of the polysaccharides used can be prevented by carrying out the process under non-cross-linking conditions, which according to the invention means that the reaction partners required for cross-linking (cross-linking agents) are not added and / or the reaction conditions required for the cross-linking reaction (e.g. the presence of the required catalysts, the temperatures required for cross-linking) are not applied.

[0061] The capsules of the present invention can be used to prepare beverages, especially hot beverages, selected from the group comprising coffee, tea, cocoa, drinking chocolate, milk or soup, or combinations thereof.

[0062] According to the invention, the beverage is preferably prepared by extracting the compostable capsule with a liquid, especially hot, selected from the group consisting of water and milk.

[0063] Corresponding preparation methods and equipment therefor are known from the state of the art. [Example]

[0064] Example 1 Spherical compacts for coffee preparation were prepared by compressing 7 g of roast and ground coffee powder in a press at 30 MPa. The coffee powder had a moisture content of 3.5%. The average particle size of the coffee powder was 400 μm ± 100 μm. Demineralized water and carboxymethylcellulose (CMC) (CMC sodium salt, medium viscosity, C4888, Sigma) were then added. An aqueous solution of carboxymethylcellulose (CMC) (Aldrich, Switzerland) was prepared. The system was prepared in the form of an aqueous solution with a carboxymethylcellulose (CMC) concentration of 4 w / w% relative to the total weight of the aqueous solution. The solution was then mixed with 40 w / w% sorbitol (based on per gram dry weight of CMC). Pellets were immersed in the aqueous CMC solution for 6 seconds and dried at 25°C in an air stream for approximately 6 minutes. Thereafter, the pellets were immersed a second time in the aqueous CMC solution for 6 seconds and dried again at 25°C in an air stream for approximately 6 minutes.

[0065] Example 2 Spherical compacts for coffee preparation were prepared by compressing 6 g of roasted and ground coffee powder in a press at 30 MPa. The coffee powder had a moisture content of 3%. The average particle size of the coffee powder was 400 μm ± 100 μm. An aqueous solution of demineralized water and sodium alginate (VIVAPUR sodium alginate, medium viscosity, JRS, Germany) was then prepared. The system was prepared in the form of an aqueous solution with a sodium alginate concentration of 1.7 wt% based on the total weight of the solution. 2 wt% of glycerol based on the total weight of the system was then added to the solution. The pellets were immersed in the aqueous sodium alginate solution for 10 seconds and dried in an air stream at 50°C for approximately 8 minutes. The pellets were then immersed a second time in the aqueous sodium alginate solution for 10 seconds and dried in air at 50°C for at least 8 minutes.

Claims

1. A compostable capsule for preparing beverages, in particular hot beverages, comprising: - a bulk material core material selected in particular from the group consisting of coffee powder, tea, cocoa, drinking chocolate, milk powder, instant coffee and dry soup and combinations thereof; - an outer covering material for enclosing said core material, said outer covering material being a compostable uncrosslinked polysaccharide; Compostable capsules containing.

2. 2. The compostable capsule of claim 1, wherein the compostable uncrosslinked polysaccharide of the outer packaging material is selected from the group consisting of starch, modified starch, pectin, cellulose, carrageenan, algin(ate), agar, pullulan, chitin, chitosan, and combinations thereof, and preferably selected from the group consisting of carboxymethyl cellulose (CMC), microfibrillated cellulose (MFC), pullulan, and chitosan, and combinations thereof.

3. 3. The compostable capsule according to claim 1 or 2, wherein the outer shell is composed of 1 to 20 layers, preferably 2 to 10 layers, more preferably 2 to 5 layers, and the layers are composed of the same or different compostable uncrosslinked polysaccharides.

4. 4. The compostable capsule of any one of claims 1 to 3, wherein the capsule is home compostable in accordance with the NF T51-800 and AS5810 certification schemes.

5. 5. The compostable capsule of claim 1, wherein the capsule is spherical in shape.

6. 6. A compostable capsule according to any one of claims 1 to 5, wherein the outer material enclosing the core material has no seams.

7. 7. The compostable capsule of claim 1, wherein the outer material surrounding the core material has a line of weakness that facilitates opening of the capsule.

8. 10. A method for producing compostable capsules, in particular compostable capsules according to any one of the preceding claims, comprising: a) providing a core material from a bulk material selected in particular from the group consisting of coffee powder, tea, cocoa, drinking chocolate, milk powder, instant coffee and dry soup, and combinations thereof; b) compressing the core material into a compacted body c) Providing a system, in particular an aqueous system, comprising a compostable uncrosslinked polysaccharide. d) applying the system to the surface of the part to be pressed, in particular by dipping, coating or spraying. e) drying the coated pellets and the process is carried out under non-crosslinking conditions.

9. 9. The method according to claim 8, wherein step d) is repeatedly carried out with the same or different systems, in particular aqueous systems, to produce 1 to 20 layers, preferably 2 to 10 layers, more preferably 2 to 5 layers on the surface of the compact.

10. The compression of the core material is performed at a compression pressure in the range of 1 to 100 MPa, preferably 5 to 50 MPa.

10. The method according to claim 8 or 9, wherein the method is carried out in

11. 11. The method according to any one of claims 8 to 10, wherein the aqueous system is provided in the form of an aqueous solution having a compostable uncrosslinked polysaccharide concentration of from 0.1 w / w% to 30 w / w%, preferably from 1 w / w% to 20 w / w%, more preferably from 3 w / w% to 6 w / w%, based on the total weight of the aqueous system.

12. 12. The method according to any one of claims 8 to 11, wherein the aqueous system additionally contains a plasticizer, in particular glycerol and / or sorbitol and / or polyethylene glycol.

13. 13. The method according to any one of claims 8 to 12, wherein step e) is carried out in an air flow by convection and / or contact drying.

14. 8. Use of a compostable capsule according to any one of claims 1 to 7 for preparing a beverage, in particular a hot beverage, selected from coffee, tea, cocoa, drinking chocolate, milk or soup.

15. 15. Use according to claim 14, wherein the preparation of the beverage is carried out by extraction of the compostable capsule with a liquid, in particular a hot liquid, selected from the group consisting of water and milk.

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