Method for micronizing coffee particles

Abstract

The invention relates to a method for micronizing coffee particles, wherein the coffee particles are micronized in an aqueous suspension comprising dissolved water-soluble coffee solids. When coffee particles are used in a coffee product, the method reduces aggregation of the coffee particles.

Description

[0001] This application is a divisional application of the international application filed on October 4, 2016, with application number PCT / EP2016 / 073629 and the invention title "Method for Micronizing Coffee Particles". The international application entered the Chinese national phase on April 4, 2018, with application number 201680058350.0. Technical Field

[0002] The present invention relates to a method for micronizing coffee particles, wherein the coffee particles are micronized in an aqueous suspension. Background Technology

[0003] Despite advancements in aroma preservation technology, some consumers still perceive soluble coffee as lacking freshness and the aroma of freshly brewed, roasted, and ground coffee. Therefore, to enhance flavor and aroma, products have been developed in which finely ground roasted and ground coffee is added to soluble coffee powder. For sensory reasons, finely ground roasted and ground coffee powder is needed to avoid a gritty or sandy sensation during consumption. However, because coffee particles contain oil, they become sticky during grinding as the oil is squeezed from the pores to the particle surface. Therefore, the particle size distribution achievable with dry grinding at ambient temperature is limited. Furthermore, finely ground coffee particles, when added to pure soluble coffee preparations, tend to aggregate during grinding and / or after remodeling in the cup. These aggregates can be seen settling to the bottom of the cup as visible black flakes. This phenomenon is considered a defect or flaw by consumers and needs to be addressed.

[0004] Micronization of coffee in concentrated aqueous phases (such as coffee extract) has been previously described, for example in GB1489166, DE3130346, and US3697288. US3652292 discloses the use of additives to prevent coffee from agglomerating during wet grinding. However, additives may be undesirable for regulatory reasons or due to consumer perception. US1214875 and EP2659783 disclose the use of pure soluble coffee powder as a carrier for co-grinding with roasted coffee particles in a spray mill. By adding a carrier that absorbs coffee oil from the particle surface, the product avoids stickiness in the mill and reduces final agglomeration in the cup; however, the required carrier mass fraction is large (approximately 50%), which adversely affects processing efficiency and flavor characteristics. There is a need to improve the methods for producing micronized coffee particles to prevent them from adhering or agglomerating when used, for example, as an ingredient in coffee products (such as instant coffee products). Summary of the Invention

[0005] The inventors have discovered that micronizing coffee particles in an aqueous suspension containing dissolved water-soluble coffee solids reduces the aggregation of micronized coffee particles in the suspension and improves the stability of the micronized coffee particles in the suspension. Therefore, this invention relates to a method for micronizing coffee particles, the method comprising: a) preparing an aqueous suspension of coffee particles containing 1-20% coffee particles and 0.1-30% dissolved water-soluble coffee solids, and having a total solids content of 40% or less; and b) micronizing the aqueous suspension to an average particle size d. 90,3 Smaller than 50 micrometers to create a suspension of micronized coffee particles. Attached Figure Description

[0006] Figure 1 : Particle size distribution of roasted and ground coffee used to prepare micronized coffee particles according to Example 1.

[0007] Figure 2 The average particle size d obtained as the grinding energy input varies 90,3 (x 90 The figure shows the results of grinding different compositions for different grinding times as described in Example 1.

[0008] Figure 3 Particle size distribution of the dried pure soluble coffee preparation as described in Example 1 after reconstruction in water.

[0009] Figure 4 Particle size distribution of the dried pure soluble coffee preparation as described in Example 2 after reconstruction in water.

[0010] Figure 5 The sedimentation of particles in different samples over time. See Examples 1, 2, and 4 for details.

[0011] Figure 6 The filter paper used to filter coffee beverage products prepared by reconstructing pure soluble coffee powder containing micronized coffee particles. See Example 5 for details. Detailed Implementation

[0012] Coffee beans are the seeds or kernels of the coffee tree, for example, from the Coffea arabica (also known as Arabica) or Coffea canephora (also known as Robusta). Coffee kernels are water-insoluble particles that are produced by breaking down coffee beans into smaller pieces using any suitable method, such as crushing, grinding, or milling (e.g., roller milling).

[0013] Water-soluble coffee solids refer to water-soluble compounds, excluding water, that are typically extracted from coffee beans using water and / or steam. Methods for extracting soluble solids from coffee beans are well-known in the field of soluble coffee production, and any suitable method can be used.

[0014] Roasted and ground coffee beans refer to coffee beans processed using roasting and grinding methods commonly used in the coffee production industry. Roasting of green coffee beans can be carried out in any suitable manner to produce the aromas associated with roasted coffee. Suitable roasting methods are well known in the art. Similarly, methods and equipment for grinding coffee beans are well known in the art, and any suitable method can be used to produce roasted and ground coffee beans according to the present invention.

[0015] The particle size of the coffee particles discussed in this application can be measured using laser diffraction techniques, for example, using commercially available instruments such as the Malvern Mastersizer 2000 (Malvern Instruments, Malvern, UK). In this application, the so-called d... 90,3 (sometimes referred to as x) 90 Size was used as a characteristic measure of the particle size distribution in coffee preparation. In a given sample, 90% of the particle mass or particle volume belongs to less than d. 90,3 The particles. We refer to d. 90,3 Instead of average particle size, because it has been found that, from a taste perspective, the largest particle size has a dominant influence.

[0016] Unless otherwise specified, quantities and ranges given as percentages (%) in this specification refer to weight percentages (weight / weight).

[0017] An aqueous suspension of coffee particles prepared according to the method of the present invention comprises 1-30% coffee particles, preferably 1-20% coffee particles, more preferably 2-20% coffee particles. The suspension further comprises 0.1-30% dissolved water-soluble coffee solids, preferably 0.1-10% dissolved water-soluble coffee solids, more preferably 0.5-5% dissolved water-soluble coffee solids. The total solids content of the suspension (including coffee particles and dissolved water-soluble coffee solids) is 40% or less, for example 1.1-40%, preferably 30% or less, for example 1.1-30%, more preferably 25% or less, for example 2.5-25% or 3-25%. The suspension can be prepared by any suitable method, such as by mixing coffee particles with an aqueous extract of coffee beans, the aqueous extract comprising a desired amount of dissolved water-soluble coffee solids; by mixing coffee particles with concentrated (e.g., dried) water-soluble coffee solids and adding it to an aqueous liquid such as water; or by any other suitable method. The order of addition of the components is not particularly critical. Suitable mixing equipment, such as a high-shear mixer, can be used to ensure proper suspension of the coffee particles and dissolution of the water-soluble coffee solids. The coffee particles used to prepare the aqueous suspension preferably have a particle size of 100 micrometers or larger. 90,3 In a preferred embodiment, the coffee particles are particles of roasted and ground coffee beans, but untreated or otherwise processed green coffee beans may also be used, depending on the intended use and characteristics of the micronized coffee particles.

[0018] Water-soluble coffee solids can also be obtained by any suitable method. Typically, as is commonly done in the production of soluble or instant coffee, water-soluble coffee solids can be extracted from coffee beans using water and / or steam. Such methods are well known in the art. The water-soluble coffee solids are preferably obtained from roasted and ground coffee beans, but untreated or otherwise processed green coffee beans can also be used. Soluble coffee solids are preferably obtained by water separation extraction from coffee beans. This means that the water-soluble coffee solids are not derived from the coffee particles used to prepare the suspension, nor from the coffee beans used to prepare these coffee particles.

[0019] All or part of the water-soluble coffee solids can preferably be obtained as a byproduct of decaffeination of coffee beans. Decaffeination is well known in the art, for example, as described in U.S. Patent No. 5,208,056. Caffeine is removed from green coffee beans by extracting them with water or with a decaffeinated coffee extract, and the resulting extract is treated with an adsorbent highly specific for caffeine. After the caffeine is absorbed, the solids remaining in the extract can be returned to the green coffee beans. The caffeine is desorbed from the adsorbent and can be used for other purposes. However, most adsorbents also adsorb many other green coffee compounds, such as aroma precursors and polyphenols; therefore, the caffeine is not pure after desorption from the adsorbent and needs to be purified before use as a component. The removed impurities are usually discarded. WO 2011 / 011418 discloses crude caffeine complexes obtained as unpurified caffeine complexes and other compounds remaining after caffeine removal from coffee beans, and the use of such crude complexes as a component. Such byproducts can be used as a source of water-soluble coffee solids in the methods of this invention. Caffeine can preferably be removed from the byproducts prior to use in this invention. A convenient way to obtain low-caffeine byproducts is by employing a desorption method that preferentially desorbs other compounds besides caffeine (e.g., polyphenols). Such a method is disclosed in WO 2014 / 072282.

[0020] The aqueous suspension of coffee particles was micronized to a particle size of d. 90,3 The particle size is less than 50 micrometers to produce a suspension of micronized coffee particles. In a preferred embodiment, the suspension of coffee particles is micronized to a particle size of d. 90,3 The particle size is 1-50 micrometers, for example 5-50 micrometers, more preferably 10-50 micrometers. Micronization refers to the physical size reduction process that reduces the particle size to the desired level of less than 50 micrometers. Coffee particles in an aqueous suspension can be micronized using any suitable method, such as ball milling, bead milling, stirred media milling, roller milling, and / or impact milling.

[0021] The method of the present invention can preferably be carried out under conditions that minimize the soluble substances in the aqueous liquid from which the coffee particles are extracted into a suspension. In a preferred embodiment, steps a) and b) are carried out at a temperature of 5-50°C, more preferably at a temperature of 5-40°C.

[0022] If concentration or drying is required, the suspension of micronized coffee particles can be concentrated by removing water, for example, through evaporation, filtration, or drying (such as spray drying or freeze drying). For instance, the suspension can be dried to produce a powder that can be used as an ingredient in food or beverage products, such as coffee beverages like instant coffee.

[0023] On the other hand, the present invention relates to a method for producing a coffee product, wherein micronized coffee particles obtained by the method of the present invention are mixed with a coffee bean extract. The coffee bean extract mixed with the micronized coffee particles can be any extract suitable for producing the desired coffee product. In a preferred embodiment, the extract is produced by extracting coffee beans with water. The coffee product is preferably a coffee beverage product, such as an instant coffee product. A coffee beverage product refers to a coffee beverage that can be consumed immediately, or a product that can be used, for example, to prepare a coffee beverage product by adding water, such as an instant coffee product. The coffee product can be presented in any suitable form, such as a liquid or dry form. In a preferred embodiment, the micronized coffee particles are mixed with the coffee bean extract such that the micronized coffee particles constitute 2-50% of the dry solids of the mixture. For example, if the desired coffee beverage product is a dry instant coffee product, the product can be dried immediately after the micronized coffee is mixed with the coffee extract produced by a conventional instant coffee production method (e.g., by spray drying or freeze drying) to produce a final instant coffee product containing micronized coffee. Therefore, in a preferred embodiment of the invention, micronized coffee particles are mixed with coffee bean extract, and then the mixture is dried to produce a dried coffee product. The coffee product can also be in liquid form, i.e., a so-called ready-to-drink product, which can be consumed directly, or it can be in the form of a liquid concentrate, which can be consumed after dilution with water, milk, and / or any other suitable liquid. Liquid concentrates can be used, for example, in vending machines for on-demand beverage preparation. Furthermore, the coffee product can be in the form of coffee-containing capsules for preparing coffee beverages in a machine by injecting hot or cold water into the capsules. The capsules can contain instant coffee and micronized coffee produced according to the method of the invention.

[0024] In a preferred embodiment, the present invention relates to a method for producing a dried coffee product, the method comprising: a) preparing an aqueous suspension of coffee particles, the aqueous suspension comprising 1-20% coffee particles and 0.1-30% dissolved water-soluble coffee solids, the total solids content being 40% or less; b) micronizing the aqueous suspension to an average particle size d. 90,3 a) forming a suspension of micronized coffee particles smaller than 50 micrometers; b) mixing the micronized coffee particles with coffee bean extract; and c) drying the mixture of micronized coffee particles and coffee bean extract to produce a dried coffee product.

[0025] Example

[0026] Example 1: Treatment of zero-concentration coffee containing 10% micronized coffee particles (MRC) in an aqueous phase at 6.5% TS (total solids). Coffee beverages are mass-produced through micronization and spray drying.

[0027] Robusta coffee (originating from Vietnam) was roasted to a CTN value of 70 and ground to a particle size of d using a three-stage roller mill. 90,3 =130µm (see Figure 1 The particle size distributions mentioned in this and the examples below were measured by laser diffraction (Malvern Mastersizer 2000, Fraunhofer algorithm, MCT oil dispersion). These pre-ground coffee particles were mixed with water at a concentration of 5% by weight. 1% by weight of powdered coffee extract (PSC) obtained by water extraction of roasted and ground coffee, and 0.5% chlorogenic acid-rich powdered coffee extract obtained as a byproduct of decaffeination of green coffee, were added to the preparation. A homogeneous mixture was prepared using a high-shear mixer (Ultraturrax, 10000 rpm, 5 minutes). The coffee suspension was micronized using a laboratory-scale planetary ball mill (Retsch PM200). For this purpose, ceramic beads (ZrO2, 0.75 mm in size) were packed into the grinding chamber, covering 80% of its volume. The coffee suspension was poured into the grinding chamber and then securely sealed. Figure 2 As shown, the mill was run at 500 rpm for 2, 5, 10 and 30 minutes to gradually monitor the reduction in particle size.

[0028] For comparison, in addition to those already specified (see...), Figure 2 In addition to the above, tests were conducted on different formulations produced as described above:

[0029] 1. The sample containing only 5% coffee particles in water, i.e., without any additives (black line with a solid square symbol). It can be seen that a balance exists between the grinding process and aggregation, resulting in d 90,3 The particle size distribution did not decrease when the particle size exceeded 60µm.

[0030] 2. Samples containing only coffee particles and 1% PSC, i.e., without added chlorogenic acid-rich extracts (black lines marked with complete triangle symbols). PSC enables the primary particles to... 90,3 Stable suspension at particle sizes smaller than 20 µm. Under very high energy inputs, the cohesive forces between fine particles dominate, and the PSC cannot prevent aggregation, which is due to the appearance d 90,3 The increase is shown.

[0031] 3. Samples containing 1% raw coffee extract or 1% low-yield coffee extract were added, i.e., extracts rich in chlorogenic acid were not added, but with a higher surfactant concentration than in Case 2. (Black lines with hollow square symbols, black lines with hollow triangle symbols). No stability advantage of the suspension was observed compared to Case 2.

[0032] 4. A sample with 0.25% purified chlorogenic acid powder added, i.e., without coffee extract (marked with a black line and a full circle symbol). Chloroganoic acid alone is not an effective stabilizer for MRC particles.

[0033] 5. A sample with 1% PSC and an additional 0.25% purified chlorogenic acid, i.e., a combination of Case 2 and Case 4 (black lines with star symbols). This formulation successfully stabilized the MRC particles, but no significant advantage was observed compared to adding PSC alone (Case 2).

[0034] 6. The performance of the stabilizer in Case 2, plus a coffee extract rich in 0.5% chlorogenic acid, is indicated by a black line with a hollow circular symbol. d was obtained. 90,3 Stable suspension of micronized coffee with a particle size of less than 10µm.

[0035] A stable suspension of MRC in water (Case 2 and Case 6) was mixed with additional pure soluble coffee powder to achieve a coffee concentration of 30% TS and a PSC / MRC (dry matter) ratio of 9 / 1. The mixture was then dried using a Niro Minor spray dryer to produce a dried powder of soluble coffee containing 10% MRC by weight.

[0036] After reconstruction in a cup (2g powder dissolved in 150mL boiling water), the particle size distribution was measured again to quantitatively analyze the aggregation effect after reconstruction. Figure 3 As shown, the suspension of MRC particles remained unchanged after spray drying and remodeling. No changes were observed in d... 90,3 The increase was significant, with absolute values ​​of 15µm (Case 6) and 25µm (Case 2).

[0037] Settlement test

[0038] A beverage sample with a 10.3% MRC content was prepared by reconstituted 2g of powder in 150mL of Vittel water at 25°C. Sedimentation tests were performed using a sedimentation balance (Mettler Toledo XP404S Excellence Plus, with density measurement kit, Balance Link Software V 4.02) by measuring the mass of the precipitate in the cup over a 5-minute settling time. Each measurement was repeated 5 times. For comparison, a commercially available coffee sample containing MRC (Kenco Millicano) was also described. The Kenco product containing 15% MRC was mixed with PSC to obtain the same MRC concentration (10%) as in the case above. The stability of the micronized particulate dispersion in the retail beverage preparation was assessed by continuous quantitative measurements of particle settling in the cup using a sedimentation balance.

[0039] Figure 5 The results of sedimentation tests are shown, comparing the sedimentation of the sample according to the present invention (Case 2: ground at 6% TS using PSC as a stabilizer) with that of the commercially available Kenco Millicano product. For the sample according to Case 2, only a trace increase in the mass of the sedimented coffee particles (2 mg) was observed within 5 minutes, meaning that the MRC showed almost no sedimentation within 5 minutes; the commercially available Kenco Millicano sample initially showed a sharp increase in sediment mass, indicating aggregate deposition. Subsequently, a slight but continuous increase in sediment mass was observed, reaching a total weight of 10 mg after 5 minutes. The mean mass of the sediment and the standard deviation of the test results are summarized in Table 1.

[0040] Example 2: Continuous micronization of retail coffee beverages containing 10% MRC in an aqueous phase at 16% TS. Spray drying

[0041] Robusta coffee (originating from Vietnam) was roasted to a CTN value of 70 and ground to a particle size of d using a three-stage roller mill. 90,3 =130µm (see Figure 1 5 kg of these pre-ground coffee granules were mixed into 25 L of water. 0.3 kg of powdered coffee extract (PSC) was added to the preparation as a stabilizer (Case 7). Meanwhile, a second batch of the same mixture was prepared, the only difference being that 0.3 kg of PSC was not added (Case 8).

[0042] A homogeneous mixture was prepared from the two preparations using a high-shear mixer (Ystral). Then, each mixture was separately fed into a wet bead mill (Hosokawa Alpine Hydro 90AHN stirred media mill). The coffee suspension was ground twice using ceramic beads (ZrO2, 1.2 mm size) at 2500 rpm, yield 20 L / h. After this wet milling process, separate products with d... 90,3 Coffee suspensions with particle size distribution characteristics of 29µm (Case 7) and 41µm (Case 8).

[0043] From two micronized coffee aqueous suspensions, 1.5 kg of aqueous extracts were separately mixed with 4.5 kg of roasted and ground coffee beans, wherein the aqueous extracts were obtained by a standard method for producing soluble coffee with a solids concentration of 50%. The mixture was then spray-dried at 160°C (NIRO SD-6.3-N) to produce a dry powder containing 10% by weight MRC of soluble coffee. A coffee beverage was prepared using this powder by adding 2 g of beverage powder to a cup and adding 150 mL of boiling water.

[0044] After reconstruction in the cup, the particle size distribution was measured again to quantitatively analyze the aggregation effect after reconstruction. Figure 4As shown, the suspension of MRC particles remained unchanged after spray drying and remodeling. No changes were observed in d... 90,3 The significant increase was 32µm (Case 7) and 36µm (Case 8), respectively.

[0045] The sedimentation tests described in Example 1 above were also performed on samples from Cases 7 and 8. Figure 5 As can be seen, a slow but continuous increase in precipitate mass was recorded in both cases. The sample with stabilizer (Case 7 – total mass after five minutes: 3 mg) performed better than the corresponding sample without stabilizer (Case 8 – total mass after five minutes: 4.6 mg).

[0046] Example 3: Continuous micronization of retail coffee beverages containing 15% MRC in an aqueous phase at 16% TS. freeze-drying

[0047] The same method as described in Case 7 of Example 2 was implemented to obtain a suspension of micronized coffee particles in water.

[0048] 2.68 kg of the suspension was mixed with an aqueous extract of 4.5 kg of roasted and ground coffee beans, wherein the aqueous extract was obtained by a standard method for producing soluble coffee with a solids concentration of 50%. The mixture was packed onto a metal tray and then freeze-dried at -40°C to produce a dry powder of soluble coffee containing 15 wt% MRC. A coffee beverage was prepared using the freeze-dried powder by adding 2 g of beverage powder to a cup and adding 150 mL of boiling water. After reconstruction in the cup, the particle size distribution was measured again to quantify the aggregation effect after reconstruction. No change in the suspension of MRC particles was observed after freeze-drying and reconstruction. 90,3 The increase was significant, with an absolute value of 40µm.

[0049] Example 4: Continuous micronization of retail coffee beverages containing 10% MRC in an aqueous phase at 33% TS. Spray drying

[0050] Robusta coffee (originating from Vietnam) was roasted to a CTN value of 70 and ground to a particle size of d using a three-stage roller mill. 90,3 =130µm (see Figure 1 1 kg of these pre-ground coffee granules were mixed with 20 kg of coffee extract at 50% TS and 12.5 kg of water to obtain a suspension with 33% coffee solids (Case 9). A homogeneous mixture was prepared from this mixture using a high-shear mixer (Ystral). The mixture was then fed into a wet bead mill (Hosokawa AlpineHydro 90AHN stirred media mill). The coffee suspension was ground twice with ceramic beads (ZrO2, 1.2 mm size) (2500 rpm, 20 L / h). After this wet milling process, a product with d90,3 A coffee suspension with a particle size distribution of 35µm.

[0051] Compared to Examples 1 and 2, this method has the advantage that the suspension obtained from the bead mill can be used directly as feed to the spray tower without further mixing steps. A NIRO SD-6.3-N spray dryer was used at 160°C to produce a dried powder containing 10% by weight MRC of soluble coffee. A coffee beverage was prepared using the resulting powder by adding 2g of beverage powder to a cup and then adding 150mL of boiling water.

[0052] The sedimentation test described in Example 1 above was also performed on the sample according to Case 9. From Figure 5 As can be seen, a slow but continuous increase in precipitate mass was recorded. After a five-minute settling time, 6 mg of precipitate was recorded. This indicates that the sample ground at 33% TS (Case 9) still exhibits good stability in terms of particle settling.

[0053] Example 5 :

[0054] Four different dried coffee beverage compositions were produced as described below. The samples were reconstructed as described in Example 1, and the reconstructed beverages were passed through filter paper (specified paper). The appearance of black spots formed by the aggregation of coffee particles on the filter paper was observed with the naked eye.

[0055] Sample 1 :

[0056] Preparation: Coffee granules were ground to a fine powder in a dry state using a low-temperature impact grinder (Hosokawa Alpine 160 UPZ). 90,3 =50µm size. The micronized coffee powder was then mixed into the concentrated coffee extract to obtain a suspension containing 66% water, 30% soluble coffee solids, and 3% MRC. A fine dispersion of MRC was obtained using a high-shear mixer (Ultra Turrax). The mixture was then dried using a Niro Minor spray dryer to produce a dry powder containing 10% by weight of soluble coffee MRC.

[0057] Appearance of the aggregates: The black dots formed in the cup after reconstruction, consisting of aggregated MRC particles, are retained on the filter paper. Their size is approximately in the range of 100-500 µm.

[0058] Sample 2 :

[0059] Preparation: Pre-ground coffee granules were prepared as described in Example 1.

[0060] 1 kg of these pre-ground coffee granules were mixed with 20 kg of coffee extract containing 50% TS and 6 kg of water to obtain a suspension with 41% coffee solids. A homogeneous mixture was prepared from this mixture using a high-shear mixer (Ystral). The mixture was then fed into a wet bead mill (Hosokawa Alpine Hydro 90AHN stirred media mill). The coffee suspension was ground twice with ceramic beads (ZrO2, 1.2 mm size) at 2500 rpm, yield 20 L / h. After this wet milling process, a product with d... 90,3 A coffee suspension with a particle size distribution of 40 µm.

[0061] Appearance of the aggregates: The black dots formed in the cup after reconstruction, consisting of aggregated MRC particles, are retained on the filter paper. Their size is approximately in the range of 100-200 µm.

[0062] Sample 3 :

[0063] Preparation: The powdered beverage composition was prepared as described in Case 7 of Example 3.

[0064] Appearance of aggregates: No aggregates were left on the filter paper that were visible to the naked eye.

[0065] Sample 4 :

[0066] Preparation: The powdered beverage composition was prepared as described in Case 9 of Example 4.

[0067] Appearance of the aggregates: There are some dark spots, but no aggregates are left on the filter paper that are visible to the naked eye.

[0068] Figure 6 Images of each sample on filter paper are shown. Incorporating dried, micronized coffee particles into the coffee extract prior to spray drying resulted in the formation of aggregates in the cup, which appeared as black dots on the filter paper. The same issue was observed with beverages made from coffee particles micronized in an aqueous phase using a bead mill at a high total solids concentration (e.g., 42%). In contrast, the samples produced as described above did not exhibit visible aggregates (Case 7 and Case 9).

Claims

1. A method for micronizing coffee particles, the method comprising: a) Prepare an aqueous suspension of coffee particles, the aqueous suspension comprising 1-20% coffee particles and 0.1-5% dissolved water-soluble coffee solids, and having a total solids content of 40% or less. as well as b) Micronize an aqueous suspension containing 1-20% coffee particles and 0.1-5% dissolved water-soluble coffee solids, with a total solids content of 40% or less, to an average particle size d. 90,3 Smaller than 50 micrometers to create a suspension of micronized coffee particles; In step a), the coffee particles are mixed with water-soluble coffee solids, which are obtained by separating and extracting coffee beans with water, and steps a) and b) are carried out at a temperature of 5-50°C.

2. The method according to claim 1, wherein the coffee particles used to prepare the aqueous suspension in step a) are particles of roasted and ground coffee beans.

3. The method according to claim 1 or 2, wherein the aqueous suspension prepared in step a) comprises 0.1-5% dissolved water-soluble coffee solids, which are obtained as a byproduct of decaffeination of coffee beans.

4. The method according to any one of claims 1-3, wherein the total solids content of the aqueous suspension prepared in step a) is 3-25%.

5. The method according to any one of claims 1-4, wherein the coffee particles used to prepare the aqueous suspension in step a) have an average particle size d of 100 micrometers or greater. 90,3 .

6. The method according to any one of the preceding claims further includes concentrating the suspension of the micronized coffee particles by removing water.

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