Capsule having a capsule body made of polysaccharide complex

Abstract

This invention relates to a preferably compostable capsule comprising a capsule body (4b) and a sealing element (10), wherein the capsule body (4b) is filled with a filler material. The capsule body (4b) comprises a polysaccharide complex. The polysaccharide complex comprises, and preferably consists of, a matrix material made of at least one polysaccharide and at least one reinforcing material. The invention also relates to a method for manufacturing such a capsule.

Description

[0001] This invention relates to a capsule and a method for preparing the same, as detailed in the preamble of each independent claim.

[0002] There are several existing methods for manufacturing compostable capsules with oxygen-barrier layers. Typically, this involves coating existing capsule bodies, such as those made from fiber casting of composite materials of biopolymers and materials with certain oxygen-barrier properties.

[0003] Furthermore, paper capsules also exist in the prior art and are described as environmentally friendly. For example, WO 2023 / 104711 describes a paper capsule. However, a drawback of paper capsules is that, contrary to popular belief, they are not particularly good at composting. The compostability problem of purely paper capsules lies in their inclusion of an additional oxygen-barrier layer.

[0004] EP3225566 describes a method for coating a capsule body with a cross-linked polysaccharide compound in a separate step. EP3736228 describes a method for manufacturing a capsule body and a step of additional coating with polyvinyl alcohol.

[0005] All of these methods have in common that they are complex and expensive because they require two processes or technologies, such as fiber casting and membrane manufacturing, which involve processing or coating separately manufactured carrier materials.

[0006] Therefore, the object of the present invention is to overcome the shortcomings of the prior art. In particular, the object of the present invention is to provide a stable capsule that has the best possible odor protection and specific oxygen barrier properties, without requiring additional layers.

[0007] This objective is achieved through the subject matter of the independent claim. Preferred embodiments can be found in the dependent claims.

[0008] A first aspect of the invention relates to a capsule, preferably compostable, comprising a capsule body and a sealing element, wherein the capsule body is filled with a filler material. The capsule body comprises a polysaccharide complex. Preferably, the capsule body is composed of the polysaccharide complex. The polysaccharide complex comprises, and preferably is composed of, a matrix material made of at least one polysaccharide and at least one reinforcing material.

[0009] By using polysaccharide complexes, the properties of capsules can be modified in various ways. For example, the stability, layer thickness, and oxygen permeability of capsules can be designed according to specific applications.

[0010] Capsules can be essentially single-layered. Single-layered capsules reduce production costs; no additional manufacturing steps are required. "Effectively single-layered" means that the capsules are distinguished by coloring at most between different filler materials.

[0011] The capsule can be composed of a homogeneous mixture of materials. Homogeneous mixtures facilitate material reuse; material separation is not required.

[0012] The capsule body can be designed to be malleable. It can determine the shape of the capsule, or, for example, can be precisely coated onto a block of filler material.

[0013] The capsule body can be in direct contact with the filler material. Therefore, an additional layer between the capsule body and the filler material, or a coating on the capsule body, can be eliminated.

[0014] The polysaccharide complex can have a thickness of less than 100 cm at a layer thickness of 100 μm. 3 / m 2 *Day*0.21 bar, preferably less than 50 cm 3 / m 2 *Day* 0.21 bar, especially preferred for samples smaller than 10 cm 3 / m 2 *Oxygen permeability (OTR) of 0.21 bar per day. Ideally, the OTR should be less than 5 cm. 3 / m 2 *day*0.21 bar.

[0015] This gives it good oxygen barrier properties without the need for additional layers.

[0016] Furthermore, traditional paper capsules are generally difficult to compost, which is another advantage of this polysaccharide complex. Composites of conventional paper capsules made from biopolymers and materials with some oxygen barrier properties are also typically difficult to compost and decompose slowly. However, since they account for less than 10% of the total complex, they are not significant in existing compostability certification programs. Using polysaccharide complex capsules not only meets but significantly exceeds the requirements of the following home compostability certification program.

[0017] "Compostable" means that the material at least meets the home composting standards of NF T 51-800:2015-11-14 (Plastics - Specification for Plastics for Home Composting) and AS 5810:2010 (Biodegradable Plastics - Biodegradable Plastics for Home Composting). This means that at a temperature of 25±5°C, at least 90% of the material decomposes (biodegrades) and releases CO2 within 12 months, and at a temperature of 25±5°C, at least 90% of the material breaks down (disintegrates) within 6 months.

[0018] The capsule is characterized by its dimensional stability, remaining undissolved or significantly altered during extraction. Additionally, the complex functions as a barrier material, preventing aroma loss, odor migration into the filler material, and oxygen ingress.

[0019] Preferably, the polysaccharide complex comprises a matrix material made of cross-linked polysaccharides. The cross-linking can be covalent, ionic, and / or coordinated.

[0020] Very stable complexes can be formed through covalent cross-linking. Covalent cross-linking is usually achieved by reacting at least one polysaccharide with a suitable cross-linking agent. Particularly suitable cross-linking agents are bifunctional organic compounds, wherein the functional groups are selected, for example, from carboxylic acids, carboxylates, activated carboxylic acids, amines, alcohols, aldehydes, and ketones. In this case, activated carboxylic acids should be understood as carboxylic acid halides, reactive esters of carboxylic acids, acid anhydrides of carboxylic acids, or other reactive derivatives of carboxylic acids.

[0021] Polysaccharides cross-linked by ionic and / or coordination bonds are particularly easy to prepare without compromising the biodegradability of the polysaccharide used. Ionic and / or coordination cross-linking can be achieved, for example, by polysaccharides having anionic groups such as carboxylic acid ester groups or sulfonate ester groups. By introducing divalent or higher valent cations, particularly alkaline earth metal ions, the anionic groups of the polysaccharide undergo ionic or coordination cross-linking, thereby forming a stable complex.

[0022] In this paper, coordinate bond refers to the interaction between electron pair donor and electron pair acceptor, such as the possible interaction between the free electron pair of the oxygen atom in a hydroxyl group and the cation.

[0023] Preferably, the matrix material is selected from alginate, starch, modified starch, cellulose, chitin, chitosan, carrageenan, pectin, agar, xanthan gum, gellan gum, dextran, galactomannan, glucomannan, guar gum, carrubin, gum arabic, stearin, pullulan, derivatives thereof, or mixtures thereof. Alginate is preferred.

[0024] These matrix materials are readily biodegradable, approved for use as food additives, and harmless. Preferably, the matrix material has oxygen barrier properties. In particular, alginate, as a natural substance in its dry state, exhibits very excellent oxygen permeability (OTR). The good barrier effect is likely based on a dense network of OH groups, which allows polar gases such as water vapor to permeate well, but does not allow non-polar gases such as oxygen to permeate.

[0025] The reinforcing material may include fibers. Preferably, the fibers are selected from: cellulose fibers; calcium alginate fibers; viscose fibers; polylactic acid (PLA) fibers; polyvinyl alcohol (PVOH) fibers; mineral fibers, preferably silica; and plastic fibers, preferably aramid fibers, polyethylene fibers, and polyamide fibers. Compostable fibers are particularly preferred, and cellulose fibers are most particularly preferred.

[0026] The fiber imparts additional stability to the polysaccharide complex.

[0027] The fiber length is preferably 0.02 to 10.0 mm, more preferably 0.04 to 5.0 mm, and particularly preferably 0.06 to 1.0 mm.

[0028] The reinforcing material may additionally or optionally include powders of at least one organic component or at least one mineral component. This can serve as an additional filler, thereby providing at least some degree of additional stability. Talc or other mineral powders, such as silica, are viable options.

[0029] The filler material is preferably a powder, a powder mixture, a briquette, a liquid, or a liquid mixture.

[0030] Filling materials can be selected from: ground coffee, instant coffee, cereal coffee, malt coffee, tea, tea granules, drinking chocolate, milk, plant-based beverages, and instant soup.

[0031] The capsule described in this invention is characterized by its excellent dimensional stability. Therefore, it should not rupture or disintegrate during transportation or user use.

[0032] The capsule, especially after being filled with filler material, can withstand a maximum force of at least 25 N, particularly at least 50 N, and especially preferably at least 100 N in a fracture strength test.

[0033] In the fracture strength test, the capsule is placed between two parallel plates of a tensile-compression testing machine (e.g., equipped with an Xforce P force sensor from Zwick / Roell). The capsule is centered on the lower plate along the tensile direction, or, for rotationally symmetric capsules, such as spherical or cuboid shapes, centered along the compression direction. The diameter of the parallel plates is at least 50% larger than the maximum diameter of the capsule. The two parallel plates are slowly brought together, and the force-displacement curve is recorded. The load is gradually increased until the shell fails. A decrease in force is observed upon fracture or breakage. The fracture strength test is terminated if the measured force is below the force drop threshold of 40% of the maximum force. The maximum force measured without damaging the shell is the fracture strength.

[0034] The sealing element can be a covering film made of an odorless material, such as polyvinyl alcohol or a corresponding copolymer. The sealing element can also be made of cross-linked polysaccharides or other readily biodegradable materials. So-called bioplastics such as polylactic acid (PLA), polyhydroxyalkanoates (PHA), polyhydroxybutyrate (PHB), and thermoplastic starch (TPS) are also suitable.

[0035] However, a capsule can also consist essentially of two halves. In this case, the first half forms the capsule body, and the second half forms the closure element. In this case, the capsule body and the closure element can be manufactured identically.

[0036] Therefore, a polysaccharide complex refers to a composite material made from a matrix material consisting of at least one polysaccharide and at least one reinforcing agent. The composite material may additionally contain other additives, such as plasticizers, fillers, pigments, dyes, water-retaining agents, flocculants, wet-strength agents, sizing agents, and / or polyvinyl alcohol or polyvinyl alcohol copolymers (PVOH). For example, PVOH can be used as a high-molecular-weight emulsifier, thereby providing additional stabilizing effects. Due to its barrier properties, PVOH can also be used as a low-molecular-weight substance.

[0037] Another aspect of the invention relates to a method for manufacturing capsules, particularly capsules as described above. The method includes the following steps:

[0038] a) Provide capsule molds,

[0039] b) Provide a molded body that complements the shape of the capsule, and then optionally:

[0040] c1) Introducing a capsule mold into a polysaccharide complex suspension containing at least one polysaccharide and at least one reinforcing material to form a preferably uncrosslinked capsule body on the capsule mold.

[0041] d1) Optionally, the capsule obtained in step c1) is introduced into the crosslinking solution.

[0042] e1) Apply the molded body to the preferably wetted capsule body;

[0043] or

[0044] c2) Introduce the polysaccharide complex suspension into the molded body.

[0045] d2) Introducing the capsule mold into the molded body to form a preferably uncrosslinked capsule body on the capsule mold.

[0046] e2) Optionally, wet the capsule formed in step d2) with a crosslinking solution;

[0047] Then proceed as follows:

[0048] f) Drying the preferably cross-linked capsule obtained after step d1) or d2), optionally after step e1) or e2).

[0049] g) Fill the capsules obtained after step f) with the filling material.

[0050] h) Seal the capsule with a sealing element.

[0051] The molded body can be a membrane or a perforated membrane. For example, perforated sheets, screens, or semi-permeable membranes made of aluminum are also suitable. The molded body can also be designed in the form of a patrix corresponding to the capsule mold. This patrix specifically refers to the negative mold of the capsule.

[0052] Capsule molds can also be metal wire mesh sleeves, or made of perforated materials similar to membranes, or exist in a dense form with no pores or a mesh structure. Capsule molds can also be preheated metal molds with steam vents. This term specifically refers to the male mold for capsules.

[0053] Preferably, the drying step is carried out on the molded body and / or in the capsule mold.

[0054] In step c2), "introduction" can refer to the molded body being at least partially filled with the suspension. This could be due to the suspension being drawn in. However, the suspension can also be applied to the walls of the molded body, for example, in the case of a female mold.

[0055] The wetting in optional step e1) or e2) may refer to immersing the molded body in the crosslinking solution, or to bringing the crosslinking solution into contact with the molded body in other ways, such as by spraying or casting. Wetting may occur inside the molded body, but it may also occur outside the molded body.

[0056] This method is characterized by the ability to produce stable and odorless capsules without a separate coating step. It is faster, more economical, and cheaper than previous methods that involved a separate coating step.

[0057] The drying in step f) can be carried out using a preheated pressing tool, preferably with a steam vent. Alternatively or additionally, the drying in step f) can be carried out in an oven and / or dryer, or by means of a pressing tool in one or more hot pressing steps. The drying time in the oven is within 3 hours, preferably 90 minutes, and particularly preferably 60 minutes. The temperature in the oven is preferably 70 to 250°C at 5% relative humidity. For example, a Binder oven (ventilated and dehumidified (5% RH)) can be used. The drying time in the dryer is preferably 6 to 12 hours, and particularly preferably 8 to 10 hours. During the hot pressing process, the temperature is 100°C to 300°C for 5 to 120 seconds. In principle, drying may include several identical or different drying steps.

[0058] At least one polysaccharide in the polysaccharide complex suspension may be selected from: alginate, starch, modified starch, cellulose, chitin, chitosan, carrageenan, pectin, agar, xanthan gum, gellan gum, dextran, galactomannan, glucomannan, guar gum, caroben, gum arabic, stearyl glucomannan, pullulan, derivatives thereof, or mixtures thereof. Alginate is preferred.

[0059] The preferred reinforcing materials are as described above.

[0060] The capsule mold can be any conceivable capsule shape. Examples include: spheres, cubes, cuboids, prisms, pyramids, cylinders, truncated cones, cones, tori, ellipsoids, etc. It should be noted that any corners and edges are preferably rounded, not sharp.

[0061] A particularly preferred polysaccharide complex suspension is an alginate-cellulose mixture.

[0062] Preferably, the alginate-cellulose mixture comprises 0.1 to 10%, preferably 0.5% to 5%, particularly preferably 1.0% alginate, preferably sodium alginate, and 0.1 to 10.0%, preferably 0.5% to 7.0%, particularly preferably 1.0% to 5.0% cellulose fibers, preferably 0.02 to 10 mm in length, preferably 0.04 to 5 mm, particularly preferably 0.06 to 1 mm. Specifically, low-concentration solutions are prepared using high-viscosity alginate, while higher-concentration solutions are prepared using low-viscosity alginate.

[0063] Unless otherwise stated, percentages given in this invention refer to weight percentage (wt. % or % (w / w)).

[0064] The viscosity of the alginate-cellulose mixture is greater than or equal to 500 mPas, preferably greater than 1000 mPas, and particularly preferably greater than 4000 mPas, as measured by a rheometer.

[0065] The yield stress of the alginate-cellulose mixture is greater than or equal to 50 Pa, preferably greater than 100 Pa, and particularly preferably greater than 150 Pa, and is measured at 30°C using a plate rheometer with a plate diameter of 50 mm.

[0066] Viscosity and yield stress were determined by recording viscosity curves via shear rheometry (linear shear rate of 5-100 l / s, t=56 s) using a rheometer with a plate-to-plate measurement system at 30°C, followed by evaluation using Casson / Steiner regression. For example, viscosity and yield stress can be determined using an Anton Paar MCR 72 rheometer.

[0067] The preferred uncrosslinked capsule can be wetted with a crosslinking solution prepared from an alkaline earth metal salt solution. However, other solutions of divalent or higher valence cations are also feasible, especially alkaline earth metal ions.

[0068] Of course, cross-linked solutions made from bifunctional organic compounds are also applicable, wherein the functional groups are selected, for example, from carboxylic acids, carboxylates, activated carboxylic acids, amines, alcohols, aldehydes and ketones.

[0069] A particularly preferred cross-linking solution is a calcium chloride dihydrate solution, preferably with a concentration of 5-20%, and more preferably a 10% calcium chloride dihydrate solution. This solution has been shown to be particularly effective for cross-linking polysaccharides, especially alginate. Furthermore, it is simple to manufacture and inexpensive. Calcium chloride dihydrate has been approved as a food additive.

[0070] The polysaccharide complex suspension may contain polyols, preferably at a concentration of 1-30%, more preferably 5-25%, and particularly preferably 10%.

[0071] Preferably, at least one polyol is selected from aliphatic polyols, preferably ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, sorbitol, erythritol, xylitol, and most particularly preferably glycerol; cyclic polyols, preferably glucose, fructose, mannose, galactose, fructooligosaccharides, inulin, isomaltulose, trehalose; sugar substitutes, preferably mannitol, isomaltulitol, maltitol, lactitol; and aromatic polyols, preferably cyanidin, corilagin, digalic acid, tannic acid, and gallic acid; and combinations thereof.

[0072] Polyols can be used as additional crosslinking agents, or incorporated into coatings, for example, through electrostatic interactions. Polyols can also be used to modulate the mechanical properties of coatings, such as their elasticity.

[0073] The filler material can be powder, powder mixture, briquettes, liquid or liquid mixture, and is preferably selected from: ground coffee, instant coffee, cereal coffee, malt coffee, tea, tea granules, drinking chocolate, milk, plant-based beverages, and instant soup.

[0074] Preferably, the formed body is a wire mesh sleeve. The wire mesh sleeve may be made of stainless steel. Preferably, the wire mesh sleeve has a mesh size of 0.01 to 0.3 mm, more preferably 0.02 to 0.21 mm, particularly preferably 0.04 to 0.08 mm, and most particularly preferably 0.05 to 0.075 mm.

[0075] The advantage of this mesh size is that polysaccharide complex suspensions cannot pass through the mesh, while cross-linked solutions, especially calcium ions, can.

[0076] The wire diameter of the metal wire mesh sleeve can be 0.01 to 0.3 mm, preferably 0.02 to 0.2 mm, particularly preferably 0.03 to 0.1 mm, most particularly preferably 0.04 to 0.06 mm, and most preferably 0.045 to 0.055 mm.

[0077] A heated metal wire mesh sleeve is preferred, which makes it easier for water to dry and evaporate.

[0078] Another aspect of the invention relates to capsules manufactured by the aforementioned method.

[0079] The invention will be explained in more detail with reference to the embodiments and accompanying drawings. These represent preferred embodiments only and should not be construed as limiting. The same reference numerals denote the same elements. They show:

[0080] Figure 1 Different process steps of the method according to the invention for manufacturing capsules according to the invention.

[0081] Figure 2 According to principle B), a dried semi-shell is manufactured under air-drying conditions.

[0082] In step A1), a capsule mold 1a made of a dense material is first immersed in an alginate-cellulose suspension 2. The alginate-cellulose suspension 2 adheres to the capsule mold 1a, forming an uncrosslinked capsule body 2a, which is then immersed in a calcium chloride bath 3. A wire mesh sleeve 5 is fitted over the gelled capsule body 4a. Subsequently, the capsule is dried according to step 6. Afterward, according to step 7, the capsule mold 1a, the dried capsule 4b, and the wire mesh sleeve 5 are separated. In step 8, the capsule 4b is filled, and then in step 9, it is sealed with a sealing element 10 in an airtight environment. Preferably, the capsule 4b is filled with a protective gas, such as nitrogen, or sealed under a modified atmosphere during sealing.

[0083] The main difference in A2 lies in the type of capsule mold 1b. Here, it is made of wire mesh to improve the drying and separation of alginate-cellulose capsules 4b.

[0084] In Example B), the alginate-cellulose suspension 2 is first filled into a wire mesh sleeve 5. The mesh of the wire mesh sleeve 5 is very fine, preventing the alginate-cellulose suspension 2 from escaping. Then, a capsule mold 1a is introduced into the wire mesh sleeve 5, compressing the alginate-cellulose suspension to form a capsule body 4a. Next, the combination of the wire mesh sleeve 5, capsule body 4a, and capsule mold 1a is immersed in a calcium chloride solution 3. Calcium can pass through the mesh of the wire mesh sleeve 5 and gel the capsule body 4a. Subsequently, drying 6, separation 7, filling 8, and sealing 9 are performed sequentially.

[0085] In Example C), the molded body is provided in the form of a female mold 11 made of wire mesh. An alginate-fiber suspension 2 is applied to the wall of the female mold 11. Subsequently, a capsule mold 1a is introduced into the female mold 11. After the capsule body is formed, it is cross-linked by wetting it with a calcium chloride solution 3. A preheated extrusion tool 12 with vapor pores is placed on the gelled capsule body 4a. Drying 6, separation 7 of the extrusion tool 12, capsule body 4b, and capsule mold 1a, filling 8, and sealing 9 are performed sequentially.

[0086] For B), the wire mesh sleeve preferably has a mesh size of 0.01 to 0.3 mm, more preferably 0.02 to 0.21 mm, particularly preferably 0.04 to 0.08 mm, and most particularly preferably 0.05 to 0.075 mm.

[0087] For all implementations other than B), especially for C), the mesh size can also have the following common dimensions:

[0088] 1) Coarse mesh: Approximately 2.5 mm - 4.8 mm (6 to 20 holes per linear inch)

[0089] 2) Grille: Approximately 0.5 mm - 1 mm (25 to 50 holes per linear inch)

[0090] 3) Fine mesh: Approximately 0.25 mm - 0.42 mm or smaller (60 to 100+ holes per linear inch)

[0091] Figure 2 The dried semi-shell manufactured according to principle B) under air drying conditions is shown.

[0092] Example 1

[0093] According to the first embodiment, a 1.00% alginate solution was prepared, which also contained 5.00% cellulose. Additionally, the solution contained 7.00% sorbitol.

[0094] In addition, metal wire mesh sleeves with a mesh size of 0.063 mm and a wire diameter of 0.050 mm were used as capsule molds and metal wire mesh sleeves, respectively.

[0095] 1-3 g of the alginate-fiber mixture is introduced into the first bent wire mesh sleeve. A second wire mesh sleeve is then placed inside the first sleeve, and the alginate-fiber mixture is distributed between the two sleeves by applying pressure and rotational motion. The amount of alginate-fiber mixture and the applied pressure can adjust the layer thickness. Excess alginate-fiber mixture can be discharged from the outlets at the edges of the two wire mesh sleeves. The two wire mesh sleeves containing the alginate-fiber mixture are completely immersed in a 10% calcium chloride dihydrate solution for 6 seconds, then rinsed with softened water. To hold the wire mesh sleeves and the alginate-fiber mixture between them in place, they are temporarily pressed together with two clothespins, and then dried in a Binder oven at 75°C for 18 minutes (ventilated and dehumidified (5% RH)). For further drying, the wire mesh sleeves are placed in a desiccator overnight. The next day, the alginate-fiber capsules can be demolded by careful rotational motion.

[0096] Example 2

[0097] According to the second embodiment, a 1.00% alginate solution was prepared, which also contained 5.00% cellulose but no sorbitol.

[0098] Furthermore, a wire mesh sleeve in the form of a female mold is used as the forming body, and a preheated metal mold with steam holes is used as the capsule mold. The wire mesh sleeve has a mesh size of 0.063 mm and a wire diameter of 0.050 mm.

[0099] Provide an aluminum pressing tool that is sanded to match the outer contour of the capsule and has small steam pores, wetted with a 10% calcium chloride dihydrate solution.

[0100] Approximately 2 g of the mixture is introduced into the interior of a curved wire mesh sleeve. Alternatively, in industrial production, it can also be drawn in via vacuum. The capsule mold is then manually inserted and pressed. The alginate-fiber mixture is distributed between the wire mesh sleeve and the capsule mold through pressure and rotational motion. The layer thickness of the alginate-fiber body can be adjusted by the amount of alginate-fiber mixture used and the applied pressure. Excess alginate-fiber mixture can be discharged from an outlet at the edge between the wire mesh sleeve and the capsule mold.

[0101] The wire mesh sleeve is then removed, and the alginate-fiber mixture formed on the capsule mold is crosslinked with a 10% calcium chloride dihydrate solution, followed by rinsing with softened water. Next, a preheated aluminum pressing tool with steam vents is placed on top, and the parts are rotated relative to each other to prevent the gelled alginate-fiber mixture from adhering to the tool. The components are secured and pressed together with metal clamps to prevent deformation of the capsules during the rapid first drying process. Subsequently, in the second drying step, it is placed in a desiccator overnight to dry completely. The next day, the alginate-fiber capsules can be demolded by careful rotating motion.

Claims

1. A capsule, preferably compostable, comprising a capsule body (4b) and a sealing element (10), wherein the capsule body (4b) is filled with a filler material, wherein the capsule body (4b) comprises a polysaccharide complex, particularly composed of a polysaccharide complex, characterized in that, The polysaccharide complex comprises a matrix material made of at least one polysaccharide and at least one reinforcing material, and preferably consists of the matrix material.

2. The capsule according to claim 1, wherein the polysaccharide complex has a layer thickness of less than 30 cm at a layer thickness of 100 μm. 3 / m 2 *Day*0.21 bar, preferably less than 20 cm 3 / m 2 *Day* 0.21 bar, especially preferred for samples smaller than 10 cm 3 / m 2 *Oxygen permeability (OTR) of 0.21 bar per day, and preferably less than 5 cm. 3 / m 2 *Day*0.21 bar of OTR.

3. The capsule according to claim 1 or 2, wherein the polysaccharide complex comprises a matrix material made of cross-linked polysaccharides.

4. The capsule according to any one of claims 1 to 3, wherein the matrix material is selected from: alginate, starch, modified starch, cellulose, chitin, chitosan, carrageenan, pectin, agar, xanthan gum, gellan gum, dextran, galactomannan, glucomannan, guar gum, caroben, gum arabic, stearin, pullulan, derivatives thereof, or mixtures thereof, preferably alginate.

5. The capsule according to any one of claims 1 to 4, wherein the reinforcing material comprises fibers, preferably selected from: cellulose fibers; calcium alginate fibers, viscose fibers; PLA fibers, PVOH fibers; mineral fibers, preferably silica; plastic fibers, preferably aramid fibers, polyethylene fibers and polyamide fibers.

6. The capsule according to claim 5, wherein the length of the fiber is 0.02 to 10.0 mm, preferably 0.04 to 5.0 mm, and particularly preferably 0.06 and 1.0 mm.

7. The capsule according to any one of the preceding claims, wherein the reinforcing material comprises a powder of at least one organic component or at least one mineral component.

8. The capsule according to any one of the preceding claims, wherein the filling material is a powder, a powder mixture, a briquette, a liquid, or a liquid mixture.

9. The capsule according to claim 8, wherein the filling material is selected from: ground coffee, instant coffee, cereal coffee, malt coffee, tea, tea granules, drinking chocolate, milk, plant-based beverages, and instant soup.

10. A method for manufacturing capsules, particularly capsules according to any one of claims 1 to 9, comprising the following steps: a) Provide capsule molds (1a, 1b). b) Provide a molded body that is complementary in shape to the capsule mold (1a, 1b), preferably a wire mesh sleeve (5). Then choose any location: c1) Introduce the capsule mold (1a, 1b) into a polysaccharide complex suspension (2) containing at least one polysaccharide and at least one reinforcing material to form a preferably uncrosslinked capsule body (2a) on the capsule mold (1a, 1b). d1) Optionally, the capsule (2a) obtained in step c1) is introduced into the crosslinking solution (3). e1) The shaped body is applied onto the preferably wetted capsule body (4a); or c2) The polysaccharide complex suspension (2) is introduced into the molded body. d2) The capsule mold (1a, 1b) is introduced into the molded body to form a preferably uncrosslinked capsule body (2a) on the capsule mold (1a, 1b). e2) Optionally wet the capsule (2a) formed in step d2) with the crosslinking solution (2); Then proceed as follows: f) Drying (6) the preferred cross-linked capsule obtained after step d1) or d2), optionally after step e1) or e2). g) Fill the capsule (4b) obtained after step f) with filling material. h) Seal (9) capsule with closure element (10).

11. The method of claim 10, wherein the drying in step f) is carried out in a preheated pressing tool, preferably a pressing tool having steam holes.

12. The method according to claim 10 or 11, wherein at least one polysaccharide in the polysaccharide complex suspension (2) is selected from: alginate, starch, modified starch, cellulose, chitin, chitosan, carrageenan, pectin, agar, xanthan gum, gellan gum, dextran, galactomannan, glucomannan, guar gum, caroben, gum arabic, stearyl glucomannan, pullulan, derivatives thereof, or mixtures thereof, preferably alginate.

13. The method according to any one of claims 10 to 12, wherein the polysaccharide complex suspension (2) is an alginate-cellulose mixture.

14. The method according to claim 13, wherein the alginate-cellulose mixture comprises 0.1% to 10%, preferably 0.5% to 5%, particularly preferably 1.0% of alginate, preferably sodium alginate, and 0.1% to 10.0%, preferably 0.5% to 7.0%, particularly preferably 1.0% to 5.0% of cellulose fibers, preferably 0.02 to 10 mm in length, preferably 0.04 to 5 mm, particularly preferably 0.06 to 1 mm.

15. The method according to any one of claims 9 to 14, wherein the preferred uncrosslinked capsule body is wetted with a crosslinking solution (3) made from an alkaline earth metal salt solution.

16. The method according to claim 15, wherein the crosslinking solution (3) is a calcium chloride solution, preferably with a concentration of 5-20%, preferably a 10% calcium chloride dihydrate solution.

17. The method according to any one of claims 9 to 16, wherein the polysaccharide complex suspension (2) comprises a polyol, preferably at a concentration of 1% to 30%, preferably 5% to 25%, particularly preferably 10%.

18. The method according to any one of claims 9 to 17, wherein the filler material is a powder, a powder mixture, a briquette, a liquid or a liquid mixture, and is preferably selected from: ground coffee, instant coffee, cereal coffee, malt coffee, tea, tea granules, drinking chocolate, milk, plant-based beverages, and instant soup.

19. The method according to any one of claims 9 to 18, wherein the formed body is a wire mesh sleeve (5) with a mesh size of 0.01 to 0.3 mm, preferably 0.02 to 0.21 mm, particularly preferably 0.04 to 0.08 mm, and most particularly preferably 0.05 to 0.075 mm.

20. The method according to claim 19, wherein the wire diameter of the wire mesh sleeve (5) is 0.01 to 0.3 mm, preferably 0.02 to 0.2 mm, particularly preferably 0.03 to 0.1 mm, most particularly preferably 0.04 to 0.06 mm, and most preferably 0.045 to 0.055 mm.

21. A capsule manufactured by the method according to any one of claims 9 to 20.

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