Capsule and use of a capsule for beverage preparation, method for producing a capsule

Abstract

Capsule for beverage preparation comprising a core material and a shell, wherein the core material contains crystallizable substances. The shell comprises a crystallization inhibitor and / or the shell is hydrophobized.

Description

[0001] Capsule and use of a capsule for beverage preparation, method for manufacturing a capsule

[0002] The present invention relates to a capsule for beverage preparation, the use of the capsule for beverage preparation and a method for manufacturing a capsule according to the preambles of the independent claims.

[0003] Capsules for beverage preparation are known from the prior art. Capsules with an aluminum or plastic shell are widely used, but have the disadvantage of being difficult to recycle. Likewise, capsules with a compostable capsule body filled with beverage substance are increasingly available.

[0004] Relatively new to the market are capsules that essentially consist of coated tablets containing a beverage substance. It has been observed that with beverage substances containing finely ground carbon dioxide (CO2), the coated tablets often develop a fluffy coating on their surface, formed by needle-shaped CO2 crystals. This crystallization usually only occurs when the capsule packaging is opened and the capsules are exposed to the surrounding air for a certain period. This fine CO2 coating affects the capsules' appearance and, although harmless, can easily be mistaken by the user for microbial growth.

[0005] The object of the invention is to overcome the disadvantages of the prior art. In particular, it aims to provide a capsule that retains an appealing visual appearance even over extended periods. This object is achieved by the devices defined in the independent claims. Further embodiments are described in the dependent claims.

[0006] An inventive capsule for beverage preparation comprises a core material, in particular a pellet, and a shell. The core material and / or shell material contains crystallizable substances. The shell includes a crystallization retarder, in particular selected from the group consisting of chlorogenic acids, citric acid, apple fibers (particle size < 50 µm), hydroxypropyl methylcellulose (HPMC), microcrystalline cellulose (MCC), microcrystalline cellulose gel (MCG), or combinations thereof. Alternatively or additionally, the shell is hydrophobized to retard crystallization.For this purpose, a) a wax polish, preferably comprising a natural wax such as carnauba wax, beeswax or rice bran wax, and / or b) a hydrophobing of the shell by adding certain lipids, preferably vegetable oils from sunflower, soy, wheat, and / or c) an inorganic barrier, in particular containing layered silicate, and / or d) a hydrophobing in particular by polymer graphing is particularly suitable.

[0007] In this and the following, "crystallizable substances" are understood to be substances that crystallize under conventional storage conditions in ambient air (23 ± 10 °C, 50 ± 20% relative humidity). Examples of such crystallizable substances include kohlrabi, amino acids, polyols, sugars, or salts. In this and the following, a "crystallization retarder" is understood to be a substance that delays, and in particular prevents, crystallization, especially kohlrabi.

[0008] In the following, a "hydrophobic shell" is understood to mean that the shell of the capsule is constructed or treated in such a way that, due to its hydrophobic nature, the migration of water-soluble substances or trace elements, in particular of Koffein, from the core material and / or the shell to the surface of the capsule is only delayed, and in particular prevented.

[0009] Stage 1 crystallization should be visible on the capsule surface no earlier than 40 days after contact with ambient air (2313 °C, 50% relative humidity). The following stage model is used to assess the crystallization:

[0010] Stage 0: no crystallization,

[0011] Stage 1: finest crystals finely distributed on the surface,

[0012] Stage 2: first areas of fine crystals visible to the naked eye,

[0013] Stage 3: Areas of crystals grow together,

[0014] Stage 4: Surface not yet fully covered,

[0015] Stage 5: entire surface completely covered with crystals.

[0016] Because the shell contains a crystallization retarder, the migration of the crystallizable substance contained in the core material and / or shell material to the surface of the shell is actively influenced, for example by complexation. Although crystallization can still occur, it is significantly delayed. Preferably, crystallization is prevented altogether.

[0017] In the case of a hydrophobized shell, for example with a wax polish, the actual crystallization process is also delayed by delaying or preventing the migration of the substance required for crystallization from the core or shell material to the surface.

[0018] The coating can be applied using a wet coating process. Such a wet coating, usually applied with an aqueous solution, allows for a completely sealed coating without seams. However, the wet coating process also exposes the core material to moisture, causing the coating to detach from the core material. The term "wet coating" explicitly includes the application of a highly viscous solution, for example, using spray coating.

[0019] The coating can be alginate-based. For example, a coating is produced by wet-applying a 1.55% w / w aqueous alginate solution containing 1.1% w / w cellulose and 9.3% w / w sorbitol, followed by a brief immersion in a 10% w / w calcium chloride solution. The crystallization retarder can then be incorporated into or applied to this solution.

[0020] The crystallization retarder can be incorporated directly into the aqueous alginate solution or applied to the shell by additional immersion in a crystallization retarder solution.

[0021] The crystallization retarder can be present in the dried coating (residual moisture of 15%) at a concentration between 0.5% and 40% (w / w), preferably between 0.6% and 30% (w / w), particularly preferably between 0.65% and 25% (w / w), and most preferably between 0.7% and 6.25% (w / w). The concentration may depend on the specific crystallization retarder used. For example, the preferred range for chlorogenic acid-containing green coffee extract is between 0.65% and 6.25% (w / w), for MCG between 3.2% and 25% (w / w), for apple fiber between 0.65% and 40% (w / w), and for citric acid preferably between 0.7% and 6.25% (w / w).

[0022] The chlorogenic acid-containing green coffee extract in powder form contained at least 20% (w / w) chlorogenic acid, preferably at least 30% and particularly preferably at least 45% (w / w) chlorogenic acid.

[0023] The core material may consist of a powder or a powder mixture selected from the group comprising: coffee, coffee blends, coffee substitute blends, tea, tea blends, cocoa, cocoa blends, drinking chocolate, milk powder, milk coffee blends, fruit milk, vegan milk substitutes, instant coffee, coffee substitute products and dry soup, and combinations thereof.

[0024] The capsule is compostable, specifically home compostable, according to the certification programs NF T 51-800 and AS 5810. "Compostable" is defined as material that meets the criteria of the certification programs NF T 51-800:2015-11-14 (Plastics - Specifications for plastics suitable for home composting) and AS 5810:2010 (Biodegradable plastics - Biodegradable plastics suitable for home composting), at least for home composting. This means that at least 90% of the material must decompose (biodegradation) with the release of COp within 12 months at a temperature of 25±5 °C, and at least 90% of the material must fragment (disintegration) within 6 months at a temperature of 25±5 °C. Therefore, the user does not need to dispose of or recycle the used capsule. The capsule can be added to the household compost.

[0025] The capsule can have a shape selected from the group consisting of sphere, ellipsoid, cube, cuboid, cylinder, lens, prism, cone, truncated cone, pyramid, truncated pyramid, torus, tetrahedron, octahedron, dodecahedron, cosahedron, and coffee bean. Of course, other shapes are also conceivable; a large number of such shapes are already known in the prior art for corresponding capsules. Preferably, the capsule is spherical. Such geometric shapes, especially if they are symmetrical, are easy to manufacture. If the capsule is rotationally symmetrical, it can, for example, be fed into a beverage preparation machine by a rolling motion. This makes it even easier for the user.

[0026] The capsule, when dry, can exhibit a maximum strength in a breaking strength test of at least 30 N, preferably at least 50 N and particularly preferably at least 80 N.

[0027] For the fracture strength test, the capsule is positioned between two parallel plates of a tensile-compression testing machine (for example, equipped with an Xforce P force transducer from Zwick / Roell). The capsule is centered on the lower plate in the extraction direction, or, in the case of a rotationally symmetrical pellet, such as a sphere or cube, in the compression direction. The plates have a diameter that is at least 50% larger than the maximum capsule diameter. The parallel plates are slowly moved together, and a force-displacement diagram is recorded. The load is increased until the capsule is damaged. A drop in force must be observed simultaneously with this crack or fracture. The fracture strength test is terminated when the measured force falls below the force drop threshold of 40% of the maximum force.The maximum measured force (F max in N) without damaging the shell is reported as the breaking strength. The elasticity of the shell is determined by the deformation of the shell until cracking or failure, and is reported as the path to failure (in mm).

[0028] The capsule shell can have a thickness of at least 50 pm, preferably at least 80 pm, and particularly preferably at least 100 pm. This thickness refers to the dry shell.

[0029] The dried capsule shell can have a moisture content in the range of 1 to 40% (w / w), preferably between 4 and 30% (w / w), more preferably between 5 and 20% (w / w), particularly preferably between 6 and 15% (w / w), and most preferably between 7% and 12% (w / w). The total residual moisture of the capsule, for example, with coffee inside, can preferably be less than 5% (w / w) after appropriate drying.

[0030] The shell may have at least one layer comprising at least one polysaccharide selected from the group consisting of: alginates, starches, modified starches, celluloses, chitin, chitosan, carrageenans, pectins, agar, xanthan gum, gellan gum, dextrans, galactomannan, glucomannan, guarana, carob, gum arabic, scleroglucan, pullulan, derivatives or mixtures thereof, preferably alginate.

[0031] The casing may contain fibers, preferably selected from the group consisting of: alginate fibers, cellulose fibers; viscose fibers; PLA fibers; mineral fibers, preferably made of silicon dioxide; synthetic fibers, preferably aramid, polyethylene, and polyamide fibers; vegetable fibers, preferably apple fibers, cocoa fibers, wheat fibers, and oat fibers; or derivatives thereof. For example, hydroxypropyl methylcellulose (HPMC), microcrystalline cellulose (MCC), and / or microcrystalline cellulose gel (MCG) are conceivable as cellulose derivatives.

[0032] The fibers provide additional reinforcement to the shell. Besides reinforcing the shell, fibers can also reduce or completely prevent bubble formation during application.

[0033] Advantageously, the casing contains a combination of at least two fibers. The use of different fibers further contributes to the casing's stability.

[0034] Preferably, the fibers have a length between 20 pm and 1500 pm. Long and short fibers are preferably mixed. The average length of the long fibers is preferably in the range between 250 pm and 1500 pm, more preferably between 300 pm and 1000 pm, and most preferably between 350 pm and 700 pm. Short fibers preferably have a length of less than or equal to 60 pm, more preferably less than or equal to 50 pm. Short fibers are therefore more granular in nature. For example, apple fiber can also be understood to mean press residues from an apple that have been dried and ground; that is, the particle shape is preferably granular and not formed as longitudinal fibers.

[0035] It is therefore possible that the shell has a combination of different fiber lengths, for example short and long fibers, and / or granular particles in combination with fibers.

[0036] The combination of different fibers and / or different

[0037] Fiber lengths also improve the optical appearance of the capsule, optimize laser readability, improve the oxygen transmission rate (OTR), and counteract bubble formation.

[0038] Preferably, the capsule has a substantially homogeneous color and a mean value of the color deviation ‘Delta E’ according to CIELAB is preferably less than or equal to 6, preferably less than or equal to 5 and particularly preferably less than or equal to 4, over at least three measurements at an optically brightest, optically medium and optically darkest point within the capsule.

[0039] CIELAB (also known as Lab color space) is a perceptual color space used to represent the colors perceived by the human eye. It consists of three axes:

[0040] - L (Luminance): Brightness of the color (0 = black, 100 = white)

[0041] - a: Color information between green (-) and red (+)

[0042] - b: Color information between blue (-) and yellow (+)

[0043] The Lab color space is device-independent, which makes it particularly useful for color comparisons and color corrections.

[0044] Delta E is a measure used to numerically quantify a visually perceived color difference. The Delta symbol represents the difference. The value of Delta E between the color points (L*, a*, b*) p and (L*, a* , b*) v is calculated according to EN ISO 11664-4 as Euclidean distance (* denotes the transformed values ​​from the CIELAB color space): A largely homogeneous color is advantageous for quality assurance, as defective products can be identified and rejected more reliably. For example, surface bubbles, which result in a less homogeneous color, are easier to detect, even with automated systems. Furthermore, any markings (laser readability) on the product, such as printed codes or labels, are more reliably readable against a homogeneous colored background, even with automated systems.

[0045] The capsule shell can also consist solely of apple fibers. Apple fibers alone also meet the visual requirements and result in a capsule with a largely homogeneous color. Therefore, the advantages described above also apply when using apple fibers.

[0046] The shell may further contain at least one polyol. Advantageously, the at least one polyol is selected from the group consisting of aliphatic polyols, preferably ethylene glycol, propanediol, butylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, sorbitol, erythritol, xylitol, and most preferably glycerol and sorbitol; cyclic polyols, preferably glucose, fructose, mannose, galactose, oligofructose, inulin, isomaltulose, trehalose; sugar substitutes, preferably mannitol, isomalt, maltitol, lactitol; and aromatic polyols, preferably cyanidin, corilagin, digallic acid, tannic acid, and gallic acid; and combinations thereof.

[0047] Another aspect of the present invention relates to a method for manufacturing a capsule, in particular a capsule as described above. The method comprises at least the following steps: - Providing a core material, preferably in the form of a pellet,

[0048] - Applying a coating by immersing the core material in at least one aqueous solution or by coating or spraying the core material with at least one aqueous solution,

[0049] - Drying of the core material and the applied shell. At least one of the aqueous solutions comprises a crystallization retarder and / or the shell is made hydrophobic. The crystallization retarder is preferably selected from the group described above.

[0050] If the core material is already provided in the form of a pellet, handling is considerably easier. A coating can then be applied particularly easily by dipping or spraying. If the core material is provided loose, the coating is preferably slipped over it. After application, the coating is dried, and the core material, if it has absorbed moisture, is also dried. To minimize moisture absorption by the core material, dusting the pellet with calcium lactate powder has proven advantageous. Especially when the coating is applied by dipping or spraying with an aqueous alginate solution, the calcium lactate powder causes the alginate to gel immediately, preventing further moisture from penetrating the core material.By additionally immersing the tablet in a calcium chloride solution, gelation can occur both from the inside and from the outside.

[0051] At least one of the aqueous solutions used in the coating application contains a crystallization retarder. A crystallization retarder prevents or at least delays the formation of crystals on the capsule surface. Additionally or alternatively, the coating can be made hydrophobic, creating a reinforced protective layer that prevents crystals from forming on the capsule surface.

[0052] The concentration of polysaccharide and especially alginate in the aqueous solution can be between 0.5 and 10.0%, preferably 0.8 and 5.0%, and particularly preferably 1.0 to 3.0% (w / w).

[0053] The concentration of crystallization retarders in aqueous solution is preferably between 0.1% and 20.0% (w / w), more preferably between 0.5% and 10% (w / w), and particularly preferably between 1.0% and 5.0% (w / w). For example, the solution may contain chlorogenic acid-containing green coffee extract between 0.1% and 1.0% (w / w). Apple fibers may preferably be used at concentrations between 0.1% and 10% (w / w), and MCG at concentrations between 0.5% and 5% (w / w). Citric acid is preferably used at concentrations around 1% (w / w).

[0054] The fiber content in the aqueous solution for producing the casing can be, for example, between 0.1 and 20.0%, preferably between 0.1 and 10.0% (w / w), more preferably between 0.5 and 10.0%, particularly preferably between 0.5 and 7.0%, and most preferably between 1.0 and 5.0% (w / w).

[0055] The concentration of polyol in the aqueous solution can be between 1 and 30%, preferably 5 to 25% and particularly preferably 10 to 20% of at least one polyol.

[0056] Advantageously, the aqueous solution used to apply the coating is additionally crosslinked with a crosslinking agent. It is possible to apply the crosslinking agent first. However, it is also conceivable to apply it together with the aqueous solution or after the aqueous solution has been applied. Furthermore, the crosslinking agent can be applied in solid form by dusting or powder coating.

[0057] The networking can be covalent, ionic and / or coordinative.

[0058] Crosslinking via covalent bonds enables a highly durable coating. This crosslinking typically occurs through the reaction of at least one polysaccharide with a suitable crosslinking agent. Functional organic compounds are particularly suitable as crosslinking agents, with the functional groups selected, for example, from the group consisting of carboxylic acids, salts of carboxylic acids, activated carboxylic acids, amines, alcohols, aldehydes, and ketones. In this context, activated carboxylic acids are understood to be carboxylic acid halides, active esters of carboxylic acids, anhydrides of carboxylic acids, or other reactive derivatives of carboxylic acids.

[0059] Polysaccharides cross-linked by ionic and / or coordinate bonds are particularly easy to produce and do not impair the biodegradability of the polysaccharide used. Ionic and / or coordinate cross-linking can be achieved, for example, using polysaccharides containing anionic groups such as carboxylate or sulfonate groups. The introduction of divalent or higher-valent cations, especially alkaline earth metal ions, then results in ionic or coordinate cross-linking of the polysaccharide's anionic groups to form a stable coating. In this context, a coordinate bond refers to an interaction between an electron pair donor and an electron pair acceptor, such as can occur between lone pairs of electrons on oxygen atoms in hydroxyl groups and cations.

[0060] The crosslinking agent is particularly preferred as an alkaline earth metal ion solution, and calcium chloride is especially preferred.

[0061] When using a calcium chloride bath, the residence time of the coated tablet in the bath can vary between 2 and 30 seconds. Preferably, bath concentrations of less than 50%, more preferably 5 to 30% (w / w), are used. The higher the concentration, the residence time in the calcium chloride bath, or the temperature of the calcium chloride bath, the faster the crosslinking reaction occurs. 10–20% solutions at 20–25°C are particularly preferred.

[0062] Another aspect of the present invention relates to a method for manufacturing a capsule, in particular a capsule as described above. The method comprises at least the following steps:

[0063] - Providing a core material, preferably in the form of a pellet,

[0064] - Providing a cover in the form of a film or a two- or multi-part capsule body,

[0065] - Enclosing the core material with the shell,

[0066] The shell comprises a crystallization retarder, preferably as described above, and / or the shell is hydrophobic.

[0067] Enclosing the core material with a foil-shaped

[0068] The encapsulation process can be similar to that used for packaging chocolates and is particularly easy to accomplish. If the core material is in bulk, a predetermined quantity can be placed on the film, and the film is then closed around the bulk material, thus enclosing the core material. Alternatively, a pouch, similar to a tea bag, can be made from the film, which is then filled and sealed. Again, the core material is enclosed by the encapsulation. The encapsulation can be alginate-based. A encapsulation in the form of a two- or multi-part capsule body can be produced, for example, as described in EP23219294.8. Such a encapsulation is particularly suitable for bulk core material but can also be used for compacted core material.The crystallization retarder and / or the hydrophobic agent can be incorporated into the shell structure or applied as a separate layer.

[0069] Crystallization retarders, such as chlorogenic acids, citric acid, apple fiber, hydroxypropyl methylcellulose, microcrystalline cellulose (MCC), microcrystalline cellulose gel (MCG), or combinations thereof, are added to the capsule shell via an aqueous solution or can form their own aqueous solution, which is applied separately. Furthermore, these substances are food-safe and have no significant impact on the capsule shell. In particular, their breaking strength and the drying conditions of the capsule are not negatively affected. Likewise, neither the taste nor the appearance of a beverage prepared from the capsule is affected.

[0070] Hydrophobing can be achieved, for example, through a wax polish, particularly carnauba wax, beeswax, and / or rice bran wax. These waxes are natural products and are well-known in the food and cosmetics industries, as well as in pharmaceuticals. Waxes are insoluble in water. Furthermore, they are indigestible and would be naturally excreted if ingested. Accordingly, hydrophobing the capsule surface with natural waxes is harmless. Hydrophobing can also be achieved by adding certain lipids, by using an inorganic barrier, and / or by polymer grafting. Hydrophobing has, at most, a negligible effect on the capsule shell. The shell's breaking strength remains unchanged, and the taste and appearance of a beverage prepared from the capsule are not significantly altered.Furthermore, hydrophobing enhances the coating's gas barrier properties, improving sensory stability. This minimizes the requirements for a water vapor barrier in the secondary packaging and can yield further advantages. For example, limited moisture exchange can ensure the long-term visibility of COp or UV laser markings within the coating. Such laser markings rely on a color change within the packaging, which tends to fade when exposed to moisture or when humidity fluctuates within the packaging.

[0071] Another aspect of the present invention relates to the use of a capsule, as described above, for preparing a beverage, in particular a hot and / or cold beverage. The beverage can be selected from the beverage groups coffee, tea, coffee substitute, cocoa, drinking chocolate, milk, vegan milk alternatives, protein drinks, food supplements or soup, or combinations thereof.

[0072] The beverage can be prepared by extracting the capsule with a liquid, particularly hot or cold, such as water or milk. A further aspect of the invention relates to a beverage preparation capsule comprising a core material, in particular a pellet, and a shell. The core material and / or shell material contains crystallizable substances such as caffeine. The shell further comprises chlorogenic acids or citric acid or apple fibers (preferably < 50 pm in length) or hydroxypropyl methylcellulose (HPMC) or microcrystalline cellulose (MCC) or microcrystalline cellulose gel (MCG) or combinations thereof, in particular in amounts as described above, especially with a fiber content in the aqueous solution for preparation and / or lengths as described above, in particular also in granular form as described above, and in particular as a crystallization retarder.

[0073] The invention will be explained in more detail below using examples, which are merely illustrative illustrations. The crystallization was optically evaluated over several days.

[0074] EXAMPLE 1

[0075] According to a first example, a 1.55% w / w alginate solution was prepared, which additionally contained 1.1% w / w cellulose and 9.3% w / w sorbitol. Furthermore, this solution contained 0.1% w / w chlorogenic acid-containing green coffee extract with 46% w / w chlorogenic acids in the powder (decaffeinated).

[0076] To produce a capsule, a spherical pellet was used, which was made from 5.9 g of coffee powder using a press and had a coating consisting of two layers. For each coating, the pellet was first immersed in the aqueous alginate solution for 10 seconds and then placed in a 10% (w / w) calcium chloride solution for 6 seconds and subsequently rinsed with water.

[0077] The coated pellet obtained in this way was dried for 18 minutes at 75°C in a drying oven with active dehumidification of the drying air after the first coating. It was then coated a second time with the provided alginate solution and calcium chloride solution and rinsed with water. A second drying process then took place for 1 hour at 75°C in the drying oven with active dehumidification of the drying air until a residual moisture content of 5% w / w was reached. After the drying time was complete, the coated, dried pellet was cooled at room temperature in a desiccator.

[0078] In an open crystallization storage test under ambient conditions (23°C, 50% relative humidity) in the laboratory, crystallization was recorded over an extended period according to the aforementioned step scheme. Compared to coated tablets with a coating lacking chlorogenic acid-containing green coffee extract, the formation of fine crystals on the surface was completely prevented by the use of chlorogenic acid-containing green coffee extract over a period of 122 days, as shown in the table below. It was found that the reference, i.e., an identically manufactured capsule whose alginate solution was not mixed with chlorogenic acid-containing green coffee extract, showed progressive crystallization on the capsule surface after only a few days.

[0079] EXAMPLE 2

[0080] According to a second example, a 1.55% was again obtained.

[0081] A 1% w / w alginate solution was prepared, additionally containing 1.1% w / w cellulose and 9.3% w / w sorbitol. A 20% w / w aqueous citric acid solution was also provided.

[0082] To produce a capsule, a spherical pellet was used, which was made from 5.9 g of coffee powder using a press. The pellet produced in this way was first dusted with 0.05 g of calcium lactate powder and then conventionally coated with three layers.

[0083] For each coating, the tablet was first immersed in an aqueous alginate solution containing 1.1% w / w cellulose and 9.3% w / w sorbitol for 10 seconds, then immersed in a 10% w / w calcium chloride solution for 6 seconds. Finally, the tablet was immersed in a 20% w / w citric acid solution for 2 seconds and then rinsed with water.

[0084] The coated pellet obtained in this way was dried for 18 minutes at 75°C in a drying oven with active dehumidification of the drying air after the first and second coatings. It was then coated a second time with the provided alginate solution, calcium chloride solution, and citric acid, and rinsed with water. A third drying cycle then took place for 2 hours at 75°C in the drying oven with active dehumidification of the drying air until a residual moisture content of 5% (w / w) was reached. After the drying time was complete, the coated, dried pellet was cooled at room temperature in a desiccator.

[0085] In an open crystallization storage test under ambient conditions (23 °C, 50% relative humidity) in the laboratory, coated tablets produced in this way showed no crystallization even after 269 days compared to a reference (coated tablet with a coating without citric acid), as shown in the table below. Conversely, the reference, i.e., an identically produced capsule whose shell is not coated with citric acid, showed progressive crystallization on the capsule surface after only a few days.

[0086] EXAMPLE 3

[0087] According to a third example, a 1.55% was again used.

[0088] A w / w alginate solution was prepared, additionally containing 1.1% w / w cellulose and 9.3% w / w sorbitol. The solution also contained 1% w / w apple fiber. The capsule was prepared identically to Example 1, except that apple fiber was used instead of the green coffee extract containing chlorogenic acids.

[0089] In the open crystallization storage test under ambient conditions (23 °C, 50% relative humidity) in the laboratory, the coated tablets produced in this way showed no crystallization over 102 days compared to a reference (coated tablet with a coating without apple fiber), as shown in the table below.

[0090] EXAMPLE 4

[0091] According to a fourth example, a 1.55% was again recorded.

[0092] A (w / w) alginate solution was prepared, which additionally contained 9.3% (w / w) sorbitol. Furthermore, the solution contained 1.75% (w / w) hydroxypropyl methylcellulose (HPMC).

[0093] The capsule was manufactured identically to Example 1, except that hydroxypropylmethylcellulose (HPMC) was used instead of the chlorogenic acid-containing green coffee extract.

[0094] In the open crystallization storage test under ambient conditions (23 °C, 50% relative humidity) in the laboratory, the coated pellets produced in this way showed no crystallization over 94 days compared to the reference (coated pellet with a coating without hydroxypropyl methylcellulose (HPMC)), as shown in the table below.

[0095] EXAMPLE 5

[0096] According to a fifth example, a 1.55% was again obtained.

[0097] (w / w) alginate solution prepared, which additionally contained 1.1% (w / w) cellulose and 9.3% (w / w) sorbitol.

[0098] To produce a capsule, a spherical pellet was used, which was made from 5.9 g of coffee powder with a press and has a coating consisting of two layers.

[0099] For each coating, the pellet was first immersed in an aqueous alginate solution containing 1.1% w / w cellulose and 9.3% w / w sorbitol for 10 seconds, then immersed in a 10% w / w calcium chloride solution for 6 seconds, and subsequently coated with

[0100] Rinsed off with water.

[0101] The coated pellet obtained in this way was dried for 18 minutes at 75°C in a drying oven with active dehumidification of the drying air. It was then coated a second time with the provided alginate solution and calcium chloride solution and rinsed with water. A second drying process then took place for 1 hour at 75°C in the drying oven with active dehumidification of the drying air until a residual moisture content of 5% w / w was reached. Following the alginate coating, a hydrophobic layer of carnauba wax was applied to the still-hot, dried pellets. For this purpose, the still-hot pellet was rubbed with a cloth soaked in molten carnauba wax, so that 0.1 g of carnauba wax was evenly distributed on the pellet surface. The coated, dried, and sealed pellet was then cooled at room temperature in a desiccator.

[0102] In the open crystallization storage test under ambient conditions (23°C, 50% relative humidity) in the laboratory, the coated and sealed tablets produced in this way showed reduced crystallization compared to the coated tablet only, as shown in the table below. Conversely, the reference tablet, i.e., an identically produced capsule without a seal, showed progressive crystallization on the capsule surface after only a few days.

[0103] EXAMPLE 6

[0104] According to a sixth example, three 1.55% alginate solutions with different fiber compositions were used. The three coating solutions differed in terms of their fiber component.

[0105] A spherical pellet, made from 5.9 g of coffee powder using a press, was used to produce a capsule. It had a coating consisting of two layers. Three types of two-layer capsules were produced, each using one of the coating solutions.

[0106] For the two-layer coating, the pellet was first immersed in the aqueous alginate solution for 10 seconds and then immersed in a 10% (w / w) calcium chloride solution for 6 seconds and subsequently rinsed with water.

[0107] The coated pellet obtained in this way was dried for 18 minutes at 75°C in a drying oven with active dehumidification of the drying air. It was then coated a second time with the provided alginate solution and calcium chloride solution and rinsed with water. A second drying process then took place for 1 hour at 75°C in the drying oven with active dehumidification of the drying air until a residual moisture content of 5% w / w was reached. After the drying time was complete, the coated, dried pellet was cooled at room temperature in a desiccator. Twenty-five coated pellets were produced per coating solution.

[0108] Five dried, coated pellets were visually assessed for the following attributes: hollow, wrinkled, and blisters. Samples exhibiting none of these attributes were classified as "OK". Following the visual assessment, the stability of the coated, dried powder pellets was determined in a fracture strength test. In the fracture strength test, the maximum force Fmax in Newtons (N) and the maximum distance to breakage (mm) were determined for each set of five coated pellets. The highest maximum force and the greatest distance to breakage were measured for the pellet coated with coating solution C, followed by the dried powder pellets coated with coating solution B. In the fracture strength test, the dried powder pellets coated with coating solution A showed the lowest maximum force F and the shortest distance to breakage, indicating low elasticity.

[0109] EXAMPLE 7

[0110] According to a seventh example, the coating solutions were

[0111] Capsules A, B, and C from Example 6 were produced. Ten coated pellets were produced for each coating solution. The production of the three different capsule types was identical to Example 6.

[0112] The variety description was laser-engraved onto the surface of the coated, dried powder pellets using a COp laser. In an open laser storage test under ambient conditions (23 °C, 50% relative humidity) in the laboratory, the visibility of the laser marking was visually assessed over a period of 3 months. As shown in the following table, the laser marking on the pellets coated with coating solution B and containing apple fiber remained 80% visible after 102 days. The laser marking on the pellets coated with coating C did not fade in 70% of cases. The reference pellets, containing only cellulose and no apple fiber, faded completely.

[0113] EXAMPLE 8

[0114] Calculation of the color difference Delta E

[0115] Three 2-layer balls each were produced using the alginate solutions A, B and C from Example 6 and according to the method described in Example 6.

[0116] The coated dried tablets were measured at three points each (light, dark, and medium areas). The measurements were performed according to CIELAB standards. For each coated dried tablet and measuring point, the

[0117] Color difference Delta E according to The results were calculated and then averaged. The results are summarized in the following table.

[0118] The values ​​show that the coated dried tablets with apple fiber (B ) have a significantly smaller

[0119] Color deviation shown is compared to the reference without apple fiber (A). The pellets coated with coating solution C are in between.

[0120]

[0121]

[0122] EXAMPLE 9

[0123] In another example, a 3D-printed mushroom-shaped support matrix was coated with alginate solution. For this, the support matrix was immersed in the aqueous alginate solution for 10 seconds, then immersed in a 10% w / w calcium chloride solution for 6 seconds, and subsequently rinsed with water. For a double coating, this step was repeated, and the coated support matrix was then dried in the laboratory for one week at ambient conditions (23°C, 50% relative humidity).

[0124] The dried alginate film was removed from the carrier matrix using a scalpel.

[0125] The oxygen transmission rate (OTR) of the dried film was then determined at 50% relative humidity and 23°C. The following table shows the composition of the four different coating solutions used to produce the dried films and the measured OTRs.

[0126] The data shows that fibers reduce the OTR of the films to varying degrees. The OTR was reduced most significantly by the microcrystalline cellulose gel.

[0127] MCC: Microcrystalline Cellulose (MCC); MCG: Microcrystalline cellulose gel

[0128] EXAMPLE 10

[0129] Another example was carried out according to the experiment from Example 7. The solid concentrations used in the coating solutions in % (w / w) and the results of the fracture strength test can be found in the following table.

Claims

Patent claims 1. A capsule for beverage preparation comprising a core material, in particular comprising a powder tablet, and a shell, wherein the core material and / or the shell contains crystallizable substances, wherein the shell comprises a crystallization retarder, in particular selected from the group comprising chlorogenic acids, citric acid, apple fibers, hydroxypropyl methylcellulose (HPMC), microcrystalline cellulose (MCC), microcrystalline cellulose gel (MCG), or combinations thereof, and / or the shell is hydrophobic.

2. Capsule according to claim 1, wherein the shell is made hydrophobic by a wax polish and / or by the addition of certain lipids and / or by an inorganic barrier and / or by polymer grafting.

3. Capsule according to claim 1 or 2, wherein the shell is applied using a wet application method.

4. Capsule according to any of the preceding claims, wherein the shell is based on alginate.

5. Capsule according to any of the preceding claims, wherein the core material comprises a powder or a powder mixture selected from the group comprising: coffee, coffee blends, coffee substitute blends, tea, tea blends, cocoa, cocoa blends, drinking chocolate, milk powder, milk coffee blends, fruit milk, vegan milk substitutes, instant coffee, coffee substitute products and dry soup, and combinations thereof.

6. Capsule according to one of the preceding claims, wherein the capsule is compostable, in particular home compostable according to the certification programs NF T 51-800 and AS 5810.

7. Capsule according to any of the preceding claims, wherein the capsule has a shape selected from the group consisting of sphere, ellipsoid, cube, cuboid, cylinder, lens, prism, cone, truncated cone, pyramid, truncated pyramid, torus, tetrahedron, octahedron, dodecahedron, icosahedron and coffee bean.

8. Capsule according to any of the preceding claims, wherein the capsule in dry condition exhibits a maximum force in a fracture strength test of at least 30 N, preferably at least 50 N and particularly preferably at least 80 N.

9. Capsule according to any of the preceding claims, wherein the shell has a thickness of at least 50 pm, preferably at least 80 pm and particularly preferably at least 100 pm in the dried state.

10. Capsule according to any of the preceding claims, wherein the shell comprises at least one layer comprising at least one polysaccharide selected from the group consisting of: alginates, starches, modified starches, celluloses, chitin, chitosan, carrageenans, pectins, agar, xanthan gum, gellan gum, dextrans, galactomannan, glucomannan, guarana, carob, gum arabic, scleroglucan, pullulan, derivatives or mixtures thereof.

11. Capsule according to any of the preceding claims, wherein the shell contains fibers, preferably selected from the group consisting of: alginate fibers, cellulose fibers; Viscose fibers; PLA fibers; mineral fibers, preferably made of silicon dioxide; synthetic fibers, preferably aramid, polyethylene and polyamide fibers; vegetable fibers, preferably apple fibers, cocoa fibers, wheat fibers and oat fibers; or derivatives thereof.

12. Method for manufacturing a capsule, in particular a capsule according to one of the preceding claims, comprising the steps: - Providing a core material, preferably in the form of a pellet, - Applying a coating by immersing the core material in at least one aqueous solution or by coating or spraying the core material with at least one aqueous solution, - Drying of the core material and the applied shell, wherein at least one of the aqueous solutions comprises a crystallization retarder and / or the shell is made hydrophobic, particularly after drying.

13. Method for manufacturing a capsule, in particular a capsule according to one of the preceding claims, comprising the steps: - Providing a core material, preferably in the form of a pellet, - Providing a cover in the form of a film or a two- or multi-part capsule body, - Enclosing the core material with the shell, wherein the shell includes a crystallization retarder and / or the shell is hydrophobic.

14. Method according to claim 12 or 13, wherein the crystallization retarder is selected from the group comprising chlorogenic acids, citric acid, apple fibers, hydroxypropyl methylcellulose (HPMC), microcrystalline cellulose (MCC), microcrystalline cellulose gel (MCG), or combinations thereof.

15. Method according to any one of claims 12 to 14, wherein the hydrophobization is effected by a wax, in particular carnauba wax, beeswax or rice bran wax and / or by the addition of certain lipids and / or by an inorganic barrier and / or by polymer grafting.

16. Use of a capsule according to any one of claims 1 to 11 for the preparation of a beverage, in particular a cold and / or hot beverage, selected from the beverage groups coffee, tea, coffee substitute, cocoa, drinking chocolate, milk, vegan milk alternatives, protein drinks, food supplements or soup, or combinations thereof.

17. Use according to claim 16, wherein the preparation of the beverage is carried out by extracting the capsule with a liquid, in particular cold or hot, selected from the group consisting of water and milk.

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