Method for producing a dissolvable coffee body, and coffee body

Abstract

In a method for producing a dissolvable coffee body, liquid coffee extract is poured into a recess of a cast mould and the coffee extract poured into the recess is frozen and then freeze-dried, thereby producing the dissolvable coffee body. In a first time period of freeze-drying, a freeze-drying device is operated at a first temperature in the positive °Celsius range and at least one first pressure of greater than 0.4 mbar. In a second time period of freeze-drying, after the first time period, the freeze-drying device is operated at at least one second temperature in the positive °Celsius range and at least one second pressure, the at least one second pressure being lower than the first pressure. The method uses relatively high temperatures in freeze-drying and only a low negative pressure compared to atmospheric pressure. This reduces the time needed for freeze-drying and a mechanically stable coffee body or coffee cube having good dissolving properties is obtained.

Description

[0001] TITLE

[0002] METHOD FOR PRODUCING A SOLUBLE COFFEE BODY AND COFFEE BODY

[0003] TECHNICAL FIELD

[0004] The present invention relates to a method for producing a soluble coffee solid and to a coffee solid produced according to such a method. The coffee solid is, for example, a cube or a tablet.

[0005] STATE OF THE ART

[0006] Coffee can be enjoyed in a variety of ways. Coffee machines that grind beans and brew the freshly ground coffee are expensive, require a lot of space, and are relatively time-consuming to prepare. Ground coffee, packaged in pre-portioned capsules, is easier and faster to brew. However, the resulting waste is considerable.

[0007] There is therefore a need for an alternative source of coffee for preparing a beverage.

[0008] One such alternative is the so-called coffee cubes available on the market. They are made from freeze-dried coffee extract and can be dissolved in water. Their shape can be, for example, a cube, a disc, or a sphere.

[0009] These coffee cubes are usually provided with additives or their surface is coated with additives to maintain a stable shape or at least to make the surface stable enough while still being soluble. Such processes are described in WO 2004 / 034798 A1, WO 2013 / 001052 A1, EP 2 725 920 B1, and EP 1 553 844 B1. US 11 375 844 B2 and CN 115067411 B describe processes for producing such coffee cubes from pure coffee as one variant. Other variants still use additives.

[0010] Some coffee cubes, sized to make a single cup of coffee or a single serving, have the problem that they are stable during production but tend to fall apart when handled. Other coffee cubes have the problem that they are already unstable during freeze-drying, expand, and tend to explode towards the end of the production process.

[0011] Furthermore, some of the manufacturing processes require a relatively large amount of time and energy, making the coffee cubes correspondingly expensive.

[0012] PRESENTATION OF THE INVENTION

[0013] It is therefore an object of the invention to provide an optimized method for producing a soluble coffee body and an optimized soluble coffee cube.

[0014] This object is achieved by a method having the features of patent claim 1 and a soluble coffee body having the features of claims 16 and 17, respectively.

[0015] In the inventive method for producing a soluble coffee solid, a liquid coffee extract is poured into a recess of a mold, and the coffee extract poured into the recess is frozen and subsequently freeze-dried, thereby obtaining the soluble coffee solid. According to the invention, in a first freeze-drying period, a freeze-drying device is operated at at least one first temperature in the positive Celsius range and at least one first pressure greater than 0.4 mbar. In a second freeze-drying period following the first period, the freeze-drying device is operated at at least one second temperature in the positive Celsius range and at least one second pressure, wherein the at least one second pressure is lower than the first pressure. The recess is typically a depression.

[0016] The positive “Celsius” range in this text also includes 0°C.

[0017] It has been shown that the use of the two freeze-drying periods at positive temperatures and the use of the first freeze-drying period at a relatively low vacuum results in a soluble coffee body whose surface, even without the use of additives, has an optimal consistency that is neither sticky nor crumbly. Mechanical stability is optimized. Flavorings or other substances that do not alter the consistency are present, depending on the design.

[0018] The solubility of the coffee powder is also guaranteed. Furthermore, an additional coating of the coffee powder is unnecessary.

[0019] Furthermore, thanks to the temperatures and pressures used, the process can be carried out in a relatively short time and thus with relatively low energy consumption.

[0020] The two freeze-drying sections can also be referred to as two freeze-drying steps.

[0021] Preferably, a liquid coffee extract with a dry matter content between 15% and 40%, preferably between 20% and 25%, is used. The liquid of the extract is preferably water.

[0022] Preferably, a liquid coffee extract with a soluble solids content of 27° Brix to 29° Brix is ​​used.

[0023] It has been shown that the use of coffee extract with the above-mentioned dry matter content and / or dry matter mass enables optimal stability. If the dry matter content is higher, depending on the variant of the inventive process, the problem arises that the product is not stable during the manufacturing process. If the dry matter content is lower, depending on the variant of the inventive process, the problem arises that the final product is not sufficiently stable.

[0024] Known devices can be used as freeze-drying devices, which preferably have pressure and temperature control.

[0025] The second period of time preferably lasts longer than the first period of time. The first period of time, or the first drying phase, preferably corresponds to a sublimation phase, i.e. the free water contained in the product is removed. In the second period of time, or in the second phase, the water bound to other molecules is removed. The transition from the first phase to the second phase preferably occurs when 90% of the water in the product has sublimated. The first period of time preferably lasts 5 to 20 hours, more preferably 7 to 10 hours, and most preferably approximately 8 or 9 hours. The second period of time preferably lasts 10 to 30 hours, more preferably 14 to 20 hours, and most preferably approximately 16 or 17 hours.

[0026] In preferred variants of the process, the division into two time periods, or two phases, enables the formation of an outer shell that is harder than the core of the coffee body.

[0027] Preferably, the second time period immediately follows the first time period. Depending on the variant of the method, the first time period transitions continuously, gradually, or abruptly into the second time period. This means that the parameters, temperature and / or pressure in the freeze-drying device settings change continuously, gradually, or abruptly during the transition phase from the first to the second time period.

[0028] In a preferred embodiment, the pressure changes abruptly and the temperature is changed during the first time period and / or the second time period. Preferably, the temperature is increased gradually, starting at the beginning of the first time period until the end of the second time period. Preferably, the temperature in the freeze-drying device is maintained for a defined period of time between the individual temperature increases.

[0029] In some variants of the method, the at least one first pressure and / or the at least one second pressure are always the same within a time period. In other variants, the at least one first pressure and / or the at least one second pressure have two or more values.

[0030] The at least one second temperature in the second time period is preferably the same as or higher than the at least one first temperature in the first time period. Preferably, it is higher. In preferred variants of the method, the temperature in the first and second time periods is 0°C to 40°C. Preferably, in the first time period, it is at least temporarily 10°C to 30°C. Preferably, the temperature in the first time period is increased from 10°C to 30°C. Preferably, the temperature in the second time period is at least temporarily 20°C to 30°C, preferably it is increased from 20°C to 30°C. In preferred variants, the temperature is approximately 30°C throughout the entire second time period.

[0031] Preferably, the at least one first pressure in the first time period is less than approximately 1.5 mbar, preferably less than approximately 1 mbar, and more preferably between 0.6 mbar and 0.9 mbar. It is preferably approximately 0.9 mbar.

[0032] Preferably, the at least one second pressure in the second time period is between 0.15 mbar and 0.25 mbar. Preferably, it is approximately 0.2 mbar.

[0033] Freeze-drying preferably comprises only these two time periods. Preferably, the mold containing the freeze-dried coffee extract is removed from the freeze-drying device immediately after the end of the second time period. Preferably, no further post-processing takes place after this step other than removal from the mold. Removal preferably also takes place immediately after removal from the freeze-drying device. In other embodiments, the mold is left in the freeze-drying device and / or in the mold for a predetermined period after the end of the second time period.

[0034] Preferably, pure coffee is processed into the coffee beans without any additives. Preferably, no subsequent coating is added to the coffee beans.

[0035] Freezing prior to freeze-drying can be performed in a single step or in multiple steps. Freezing prior to freeze-drying is preferably performed in exactly two steps.

[0036] Freezing is preferably carried out at a freezing rate of less than 0.5°C per minute. This also reduces energy consumption and results in an optimal consistency of the final product.

[0037] Preferably, a first freezing step takes place at a temperature that leads to the formation of large ice crystals. Preferably, the temperature is greater than -19°C, more preferably approximately -18°C.

[0038] The second freezing step preferably takes place after a few hours, for example, after 6 to 24 hours, more preferably after approximately 8 hours. The second freezing step is carried out at a lower temperature and preferably lasts the same amount of time or longer. The coffee extract is preferably frozen to a final temperature of less than -40°C, preferably approximately -45°C. The duration of the second freezing step is preferably 10 to 36 hours, more preferably approximately 12 or 16 hours, or 12 to 16 hours.

[0039] The coffee body produced using the processes described above, also called a coffee cube, has a different final shape depending on the mold. It is preferably a cube. However, it can have any other shape, for example, it can be a disc-shaped tablet, a cuboid, a sphere, a hemisphere, egg-shaped, or rod-shaped. It preferably consists of pure coffee without additives and preferably without any coating.

[0040] The coffee body preferably contains a quantity of coffee suitable for preparing one serving, preferably from 75 ml to 200 ml.

[0041] The coffee body preferably has a dry mass of 0.5 g to 5.0 g, preferably 1.0 g to 2.5 g. This dry mass is preferably suitable for dissolving in 50 ml to 400 ml of liquid, preferably 75 ml to 200 ml, to produce a tasty coffee. Even more preferably, it is dissolved in 100 ml to 150 ml of liquid.

[0042] The coffee base can be dissolved in a hot, and preferably warm, or cold, liquid. The liquid is preferably water, milk, or a water / milk mixture. Instead of cow's milk, soy milk, rice milk, or other vegan milk alternatives can also be used. The term "soluble" should be understood accordingly.

[0043] Further variants of the method and further embodiments are specified in the dependent claims. DESCRIPTION OF PREFERRED EMBODIMENTS

[0044] A coffee extract of the "Veracruz" type, based on Arabica beans, or an extract from Robusta coffee beans is preferably used. Production is carried out by hot extraction under pressure or, alternatively, by cold extraction. The coffee extract preferably has a soluble dry matter content of 27 to 29° Brix.

[0045] No additives were added to the coffee extract during the entire process. The coffee extract was poured into cube-shaped recesses in a silicone mold. Other types of molds can also be used, particularly regarding shape and / or material.

[0046] The mold filled with the coffee extract was placed in a first freezer compartment at -18°C for 8 hours, whereby large ice crystals were formed.

[0047] After 8 hours, the mold was placed in a second freezer compartment at a temperature of -45°C. The mold remained there for 12 hours. The water in the coffee extract was then completely frozen.

[0048] The mold was then removed from the second freezer compartment and placed in a chamber of a freeze-dryer.

[0049] The following freeze-drying program was used in the freeze-dryer: In a variant of the process, the following freeze-drying program was used:

[0050] Zones 1 to 14 were run through sequentially. In this example, the zones do not represent different locations within the freeze-dryer, but rather the same location during consecutive periods of time during which different temperatures and negative pressures prevailed in the chamber.

[0051] In the first example, zones 1 to 10 form the first time period or phase of the freeze-drying process, while zones 11 to 14 form the second time period or phase of the freeze-drying process. In the second example, zones 1 to 7 form the first time period, and zones 8 to 14 form the second time period.

[0052] After the freeze-drying process was completed, the mold was removed from the freeze-drying device and the freeze-dried coffee cubes were removed from the mold and packed together in an airtight box or airtight bag.

[0053] The coffee cubes obtained in these processes were cubic in shape and had a dry mass of approximately 1.5 g. Each coffee cube was used to prepare 100 ml or 100-150 ml of coffee, and was soluble in hot, warm, and cold water. The inventive process uses relatively high temperatures for freeze-drying and only a slight negative pressure compared to atmospheric pressure. This has surprisingly led to a reduction in the time required for freeze-drying, resulting in a mechanically stable and readily soluble coffee solid.

Claims

PATENT CLAIMS 1 . A method for producing a soluble coffee body, wherein a liquid coffee extract is poured into a recess of a casting mold and wherein the coffee extract poured into the recess is frozen and subsequently freeze-dried, whereby the soluble coffee body is obtained, characterized in that in a first period of freeze-drying, a freeze-drying device is operated with at least a first temperature in the positive "Celsius range and at least a first pressure of greater than 0.4 mbar and that in a second period of freeze-drying following the first period of time, the freeze-drying device is operated with at least a second temperature in the positive "Celsius range and with at least a second pressure, wherein the at least one second pressure is lower than the first pressure.

2. Process according to claim 1, wherein a liquid coffee extract having a dry matter content between 15% and 40%, preferably between 20% and 25%, is used.

3. A process according to any one of claims 1 or 2, wherein a liquid coffee extract having a soluble solids content of 27° Brix to 29° Brix is ​​used.

4. The method according to any one of claims 1 to 3, wherein the second time period lasts longer than the first time period.

5. The method according to any one of claims 1 to 4, wherein the second time period immediately follows the first time period.

6. The method according to any one of claims 1 to 6, wherein the first time period lasts 5h to 20h, preferably 7h to 10h, and the second time period lasts 10h to 30h, preferably 14h to 20h.

7. The method according to any one of claims 1 to 6, wherein the at least one second temperature in the second time period is preferably equal to or higher than in the first time period, wherein the at least one first and the at least one second temperature in the first and second time periods is 10°C to 30°, wherein the at least one second temperature is preferably 20°C to 30°C.

8. The method according to any one of claims 1 to 7, wherein the at least one first pressure in the first time period is preferably less than 1.5 mbar, preferably less than 1 mbar and more preferably between 0.6 mbar and 0.9 mbar.

9. A process according to any one of claims 1 to 8, wherein pure coffee is processed in the process without the use of additives.

10. The method of any one of claims 1 to 9, further comprising preparing the frozen coffee extract.

11. The method according to claim 10, wherein the preparation of the soluble coffee body comprises exclusively the preparation of the frozen coffee extract or the use of frozen coffee extract and freeze-drying.

12. The method according to claim 11, wherein the coffee extract is frozen at a freezing rate of less than 0.5°C per minute.

13. The method according to any one of claims 10 to 12, wherein the coffee extract is frozen in a first freezing step and in a second freezing step following the first freezing step, wherein the second freezing step takes place at a lower temperature than the first freezing step, preferably the first freezing step takes place at a temperature of greater than -19°C, preferably equal to or greater than -18°C, and preferably the coffee extract is frozen in the second freezing step to a temperature of approximately -40°C or approximately -45°C.

14. The method according to claim 13, wherein the coffee extract is frozen in the first freezing step for 6h to 24h, preferably 8h, and / or in the second freezing step for 10h to 36h, preferably 12h to 16h.

15. The method according to any one of claims 10 to 14, wherein the coffee extract is frozen for several hours, preferably for 6 hours to 60 hours, more preferably between 16h and 60h.

16. Soluble coffee solids prepared by the process according to any one of claims 1 to 15.

17. Soluble coffee body, preferably produced by the process according to one of claims 1 to 15, wherein the coffee body comprises an amount of coffee for preparing one portion, in particular one cup of coffee, and wherein the coffee body does not comprise any additives influencing a consistency of the coffee body and does not comprise a coating containing such additives.

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