Spray-dried coffee product and production method

Abstract

The present invention relates to a method for producing coffee powder, the method comprising: a) providing an aqueous coffee extract comprising 30 to 55 wt% soluble coffee solids and 1 to 10 wt% oil, wherein the aqueous coffee extract consists of water and coffee-derived components; b) subjecting the aqueous coffee extract to a two-stage homogenization process, wherein the first stage is carried out at 200 to 1000 bar and the second stage is carried out at 10 to 100 bar, to provide a homogenized coffee extract; c) spray drying the homogenized coffee extract.

Description

[0001] The present invention relates to a process for providing an improved spray-dried coffee product and to the spray-dried product. In particular, the present invention relates to spray-dried coffee having an improved sensory profile obtained by spray-drying an oil-enriched homogenized coffee extract.

[0002] It is well known to extract roast and ground coffee with water to obtain a coffee extract high in coffee solids. Furthermore, it is well known to dry such extracts by spray drying or freeze drying to obtain a soluble beverage powder. This beverage powder can then be reconstituted with hot water at the consumer's convenience to obtain a coffee beverage. It is desirable for such homemade coffee beverages to have a taste similar to that of coffee shop beverages.

[0003] Industrial production of soluble coffee products is associated with higher temperatures and pressures than coffee shop brewing systems. This allows for higher yields from coffee beans and therefore higher profitability, but has the side effect of allowing coffee to take on undesirable processed flavor notes. To avoid this, a number of different technologies are employed, including aroma capture methods, to ensure that flavor molecules from the initial, lower-temperature extraction step are retained.

[0004] An example of a conventional coffee extraction process involves the following steps. Green coffee beans are roasted to the desired roast level and ground to a particle size of 2 to 3 mm. They are then subjected to a column extraction process with a first step at approximately 150°C and a second step at a higher temperature of approximately 185°C. The coffee extracts washed from the beans in each extraction step are combined, concentrated, and dried. The process is semi-continuous, using multiple extraction columns.

[0005] EP0826308 discloses a process for countercurrent extraction of soluble coffee solids. In a first extraction stage, soluble coffee solids are extracted from roast and ground coffee using a primary extraction liquid at a temperature of 80°C to 160°C. Then, in a second extraction stage, soluble coffee solids are extracted from the partially extracted grounds using a secondary extraction liquid at a temperature of 160°C to 190°C, the coffee grounds having at least 25% by weight of soluble coffee solids extracted therefrom. The coffee grounds obtained from the second extraction stage are discharged and thermally hydrolyzed in a hydrolysis stage at a temperature of 160°C to 220°C for 1 to 15 minutes. In a third extraction stage, soluble coffee solids are extracted from the hydrolyzed coffee grounds using a third extraction liquid at a temperature of 170°C to 195°C to provide extracted coffee grounds and a hydrolyzed coffee extract. A soluble coffee product is obtained containing at least 30% sugars, the sugars comprising less than 1% furfural derivatives, less than 4% monosaccharides, less than 10% oligosaccharides and at least 19% polysaccharides, the sugars having a weight average molecular weight greater than 2000 units and a polydispersity greater than 3.

[0006] EP0916267 discloses a process for continuously extracting water-soluble solids from solid particles containing water-soluble solids, such as roasted and ground coffee, to provide an extract product in one or more extraction stages. In each extraction stage, a slurry containing the particles to be extracted and the extract is introduced into an extraction reactor, for example, immediately above a solid-liquid separator, to form an upwardly moving packed bed. Particles are scraped from the packed bed to define the upper surface of the packed bed. An extraction liquid is introduced into the extraction reactor above the upper surface of the packed bed. A portion of the extraction liquid is obtained by percolating through the packed bed to extract water-soluble substances from the particles in the packed bed to form an extract. The remaining portion of the extraction liquid entrains the particles scraped from the packed bed to provide a spent particle slurry. The spent particle slurry is removed from the extraction reactor. The extract is removed from below the packed bed, and at least a portion of the extract forms the extract product. The extraction stages may be separated by one or more solubilization stages.

[0007] EP1069830 discloses a process for recovering aroma components from coffee. A slurry of coffee grounds in an aqueous liquid is stripped to remove aroma components from the slurry. Gas stripping is performed in a substantially countercurrent manner to provide an aromatized gas containing aroma components. The aroma components are then collected from the aromatized gas. The aroma components can be added to a concentrated coffee extract prior to drying. The resulting coffee powder has a significantly enhanced and improved aroma and flavor, and contains higher levels of furans and diketones.

[0008] US3682649 discloses cold water pressure extraction of roasted coffee in whole bean or ground form to obtain a high-quality coffee extract and partially extracted coffee that can be further processed. The coffee extract can be dried to obtain high-quality soluble coffee. The partially extracted coffee can be further extracted by standard percolation techniques or dried and used as conventional roast and ground coffee.

[0009] US Pat. No. 3,652,292 discloses the production of an instant coffee powder comprising soluble coffee solids prepared by extraction as an aqueous medium, to which wet-ground colloidal particles of roasted or extracted roasted coffee are added. The colloidal particles comprise approximately 3% to 40% by weight of the total weight of the coffee product. The colloidal particles are stabilized to prevent flocculation by adjusting the pH to no more than 5.2, and the particles are encapsulated in dry soluble coffee solids to form an instant coffee product having the aroma, flavor, and turbidity of freshly brewed coffee.

[0010] EP1795074 relates to a method for providing a concentrated coffee extract that is rich in aroma components released when roasted coffee beans are ground and has a controllable amount of coffee oil depending on the intended use and purpose, and to a process for industrially producing the concentrated coffee extract. According to the present invention, this objective is achieved by separating a distillate containing aroma components, a liquid containing coffee oil, and the coffee extract from a slurry obtained by wet-grinding roasted coffee beans, and then adding the distillate containing aroma components and the liquid containing coffee oil back to the coffee extract after concentrating the coffee extract.

[0011] US2015 / 296829 describes a method for surface treatment of soluble coffee to improve its flavor and aroma. The method involves sequentially adding 0.5 to 4 wt% coffee oil and then 1 to 3 wt% water to the surface of existing soluble coffee powder.

[0012] EP0916267 discloses a method for extracting coffee from roasted and ground coffee beans. Specifically, the product obtained from the extraction reactor 10 via the lower outlet 30 is a liquid coffee extract 32. This is separated into a recycled coffee extract 42, which is used to slurry fresh coffee grounds, and a product coffee extract 20 (paragraph

[0026] ). The liquid exiting via the lower outlet 30 is liquid that has passed through the screen 14, which retains the coffee solids.

[0013] US3361571 relates to a method for obtaining a decaffeinated coffee product.

[0014] EP1795074 relates to an extraction process for providing a clear, concentrated coffee extract containing aroma. Key to this process is low-temperature wet milling extraction. As a result of the low temperature, the extract contains low levels of mannans, which cause sedimentation and contribute to the insoluble coffee fraction. Furthermore, the extract undergoes three clarification steps (coarse filtration, centrifugation, and fine filtration).

[0015] Since the production of liquid (i.e., aqueous) coffee extracts and dried soluble coffee products is associated with flavor differences compared to freshly prepared coffee beverages in a coffee shop environment, there has always been a goal to improve the production process to achieve improved products. A common approach to improving the flavor of dried soluble coffee products is to add finely ground roasted coffee particles to the coffee extract before drying. The addition of such particles is usually controlled to avoid excessive deposition in the beverage, but generally does have a beneficial effect on the product flavor. The presence of small particles can also contribute to the observed mouthfeel.

[0016] GB 1399650 discloses improvements in the agglomeration of water-soluble instant food powders.

[0017] US2006 / 0035000 discloses a soluble coffee product with improved flavor and aroma, the coffee product comprising soluble particulate coffee and non-aromatic coffee oil.The process relies on solvent extraction of coffee oil or pressing the coffee oil out of coffee beans under pressure.

[0018] US2015296829 relates to a method of adding coffee oil to the surface of already formed coffee powder to improve the aroma of the product.

[0019] US 2014 / 106055 relates to a technology for producing super concentrated liquid coffee that is shelf-stable at ambient temperature without the need for refrigeration or freezing.

[0020] WO2020136146 discloses an instant coffee composition for forming a coffee beverage, wherein the composition comprises at least 6 wt% of an insoluble coffee sediment fraction, which comprises 1 wt% or less of arabinose when analyzed after acid hydrolysis.

[0021] It would therefore be desirable to provide improved methods for preparing coffee products, improved coffee products and / or to address at least some of the problems associated with the prior art, or at least provide a commercially viable alternative.

[0022] According to a first aspect, there is provided a method for producing coffee powder, the method comprising:

[0023] a) providing an aqueous coffee extract comprising 30% to 55% by weight soluble coffee solids and 1% to 10% by weight oil, wherein the aqueous coffee extract consists of water and coffee-derived components;

[0024] b) subjecting the aqueous coffee extract to a two-stage homogenization process, wherein the first stage is carried out at 200 to 1000 bar and the second stage is carried out at 10 to 100 bar, to provide a homogenized coffee extract;

[0025] c) spray drying the homogenized coffee extract.

[0026] The present invention will now be further described. In the following paragraphs, different aspects of the present invention are defined in more detail. Unless otherwise clearly stated, each aspect so defined may be combined with any one or more other aspects. In particular, any feature indicated as preferred or advantageous may be combined with any other one or more features indicated as preferred or advantageous.

[0027] The present invention provides a method for producing coffee powder, and in particular, spray-dried coffee powder. Spray-dried coffee powder is considered an "instant" coffee product because it forms a beverage essentially immediately upon addition of hot water (e.g., 80°C to 95°C). Such products can be supplemented by adding a small amount of finely ground roast and ground coffee to improve flavor or appearance, as is well known in the art. This can be added before or after the spray-drying step.

[0028] This patent application refers to "solids." These are the materials that remain after all the water has been removed. So, if you take a coffee beverage and remove the water (via evaporation), you'll be left with coffee solids. These coffee solids will include soluble coffee solids and insoluble coffee solids. Insoluble coffee solids will include roasted and ground coffee material as well as coffee oils. A further distinction is made herein to an insoluble coffee sediment fraction, which is the non-oil portion of the insoluble coffee solids.

[0029] Preferably, the aqueous coffee extract comprises 35% to 70% total solids (i.e., soluble and insoluble coffee solids) by weight, and more preferably, the aqueous coffee extract comprises 45% to 55% total solids by weight. Below 35% total solids, the spray drying process is inefficient, requiring the removal of large amounts of water. Above 70% total solids, the solids level may be so high that spray drying becomes difficult to perform.

[0030] The method comprises providing an aqueous coffee extract comprising 30% to 55% by weight of soluble coffee solids and 1% to 10% by weight of oil, wherein the aqueous coffee extract is composed of water and coffee-derived components. The coffee solids primarily comprise soluble coffee solids, but will also contain a portion of insoluble coffee solids, including coffee oil. Advantageously, the insoluble coffee solids comprise a non-oil insoluble coffee sediment fraction. This can be obtained by supplementing the aqueous coffee extract with finely ground roasted coffee material. Alternatively, the insoluble coffee sediment fraction will naturally result from the manufacturing process. As shown in the examples, small amounts of insoluble matter are present in most instant coffee products.

[0031] Preferably, the aqueous coffee extract contains 1.5 to 5 wt% coffee oil, and more preferably 2 to 4 wt% coffee oil. As shown in the examples, it is unusual for soluble coffee to contain such high levels of oil.

[0032] Preferably, the aqueous coffee extract comprises 45 to 55 wt% soluble coffee solids as this means less water needs to be removed during the drying process. This improves the efficiency of the process.

[0033] Preferably, the aqueous coffee extract is obtained by a novel extraction process as described in International Patent Application No. PCT / EP2019 / 086859, filed on December 20, 2019, the entire contents of which are incorporated herein by reference. As described below, this process inherently provides an aqueous coffee extract having a high level of coffee oil. In contrast, most known roast and ground coffee extraction techniques produce extracts with low levels of oil, either intentionally to avoid producing a product with oily slicks on the surface of the beverage or unavoidably as a result of the steps taken. Furthermore, it has been found that this process inherently provides a non-oil insoluble coffee sediment fraction to improve consistency and flavor, without the need for supplemental extracts.

[0034] Advantageously, the method thus avoids the need for a separate step to obtain coffee oil, as it does not rely on the addition of a separate oil source, such as that obtained by pressing (pressing and crushing dry coffee beans) or solvent extraction (such as with CO2 or an organic solvent). In contrast, when coffee beans are very finely ground (<600 microns), they have been found to naturally release high levels of coffee oil when subjected to slurry extraction. Therefore, the preferred method used herein does not have any step in which coffee oil is added to the aqueous coffee extract.

[0035] The process of the first aspect as herein described avoids the presence of a surface oil film, but the further addition of a homogenization step as herein described provides additional unexpected advantages. In particular, the sensory profile including taste and mouthfeel is altered and improved. Without wishing to be bound by theory, it is speculated that the stable oil and water emulsion produced is used to better protect the desired flavor components in the coffee during the spray drying process. The stable oil and water emulsion also allows for the inclusion of higher levels of flavor added back into the coffee, making it possible to obtain a highly aromatic product. That is, the coffee oil not only protects the flavor in the coffee, but has also surprisingly been found to protect a greater proportion of the volatile flavor compounds added to the spray-dried coffee extract.

[0036] The method further comprises subjecting the aqueous coffee extract to a two-stage homogenization process, wherein the first stage is carried out at 200 to 1000 bar and the second stage is carried out at 10 to 100 bar, to provide a homogenized coffee extract. Homogenization equipment is well known in the beverage field and is particularly used in dairy processing to stabilize emulsions. Providing a two-step process is particularly preferred because a single stage tends to cause coalescence and aggregation of oil. In addition, using a high-pressure step followed by a low-pressure step results in a more stable emulsion. The inventors have discovered that a homogenizer is the only way to achieve the desired very fine oil-in-water emulsion required for a beneficial end product.

[0037] Preferably, the first stage is carried out at 500 bar to 1000 bar, such as 600 bar to 800 bar. It has been found that these higher ranges for the first step provide smaller average (D50) oil droplet sizes with greater stability. Preferably, the second stage is carried out at 10 bar to 50 bar. It has been found that such process conditions maximize the stability of the emulsion. For a given portion of the extract, homogenization occurs very quickly and, under the determined conditions, the emulsion remains stable for several hours (if not days).

[0038] The coffee extract is preferably homogenized to a D50 oil droplet size of less than 8 microns, preferably less than 7 microns, more preferably less than 5 microns and most preferably less than 4 microns, such as preferably 1 to 7 microns and most preferably 1 to 5 microns, more preferably 2 to 4 microns, more preferably 2.5 to 3.5 microns. The inventors have found that allowing oil droplets within this size range to persist in the reconstituted beverage obtained from the spray-dried powder provides an improved creaminess. In contrast, for larger oil particles, the perception is that the beverage has less consistency (i.e., too much water). The oil droplets also persist during storage of the extract, so that no special process restrictions need to be imposed before spray drying.

[0039] The coffee extract is preferably provided to the homogeniser at a temperature of from 40°C to 90°C and a pressure of from 1.5 bar to 10 bar. This temperature is required to ensure that the high solids extract is pumpable, but not so much that it degrades the composition.

[0040] Finally, the method involves spray-drying the homogenized coffee extract. Spray-drying processes are well known in the art. The product is a spray-dried instant coffee powder. Exemplary spray-drying conditions are 40°C to 90°C and 20 to 500 bar. The product moisture content is preferably 1 to 5% by weight, such as approximately 3% by weight.

[0041] Preferably, the homogenized extract is immediately placed in the spray dryer without storage. This allows the use of a single high-pressure pump to drive the homogenization and spray drying steps for energy and process efficiency. Designs of homogenizers that can be driven by a single pump are known in the art. Preferably, the extract is spray dried for 5 minutes, and preferably homogenization is performed within about 1 minute.

[0042] Before spray-drying the coffee, it can be subjected to a gas injection step. This can be performed before or after the homogenization step and has no particular effect on the product. This reduces the density of the final product by increasing its porosity. An example of a gas injection method is described in US Pat. No. 5,882,717. The gas can be added in any suitable amount and at any pressure, with pressures ranging from 1 bar to 500 bar being known. Preferred pressures are in the range of 10 bar to 100 bar, such as 40 bar. Adding gas to the product allows for a product high in oil and aroma, as well as a low density (especially CO2) or a high product crema (especially N2). Most preferably, the injected gas is nitrogen to produce crema.

[0043] As will be appreciated, spray drying is one of several techniques used to produce coffee powder, including others such as freeze drying. Freeze drying involves taking a fresh coffee extract, cooling it to approximately -40°C, and then subliming the water. This results in an open-pore product. In contrast, spray drying involves spraying the fresh extract into the top of a spray-drying tower using hot circulating gas. Consequently, spray-dried powders typically dry faster, hotter, and are more likely to degrade the processed extract. The product also tends to have fine, closed pores.

[0044] From a process perspective, spray drying is preferred because it can process larger volumes more quickly. Consequently, there's a common consumer perception that spray-dried coffee may lack authentic coffee aroma. This is likely due to the loss of volatile coffee solids during the more demanding drying process. Consequently, freeze-dried products are generally perceived as higher quality and are expected to have a better sensory profile.

[0045] However, the present inventors have discovered that providing a high-oil-content aqueous extract that is homogenized prior to spray drying results in an improved product. This is particularly true where the extract has been supplemented with a recovered aroma fraction, as this unexpectedly appears to be preserved throughout the drying process. Thus, the present inventors have been able to provide a spray-dried coffee product with a flavor and mouthfeel that meets or even exceeds that of freeze-dried coffee powder.

[0046] Thus, according to a preferred embodiment, the aqueous coffee extract is an aromatized coffee extract. That is, the aqueous coffee extract comprises the aroma fraction obtained from freshly roasted and ground coffee.

[0047] Aroma recovery process is known in the art, and is sometimes referred to as steam stripping.In a typical steam stripping process, a coffee (average particle size 2mm to 3mm) filled column is filled with a roasted and ground coffee (average particle size 2mm to 3mm) moistened with a small amount of water (by the weight of coffee beans about 0.5% by weight) before contacting with steam.Then the steam distillate is reclaimed as the aroma fraction. The process is preferably carried out so that aroma stripping accounts for 1% to 15% by weight of the starting weight of the coffee (and water) roasted and ground. That is, the stripping process removes and reclaims the volatile components of the weight fraction comprising raw coffee. Preferably, it is carried out so that aroma stripping accounts for 5% to 12% by weight of the starting weight of the coffee (and water) roasted and ground, and more preferably about 10% by weight.

[0048] Another method of aroma recovery involves passing steam through a slurry of finer ground coffee beans, as discussed below. This process is preferably performed so that aroma stripping represents 1 to 15 weight percent of the starting weight of the slurry comprising roast and ground coffee. Preferably, it is performed so that aroma stripping represents 5 to 12 weight percent, and more preferably about 10 weight percent, of the starting weight of the slurry. This level of recovery by either technique yields a majority of the volatile flavor and aroma compounds without the need to recover an excess water fraction.

[0049] The steam distillate obtained from any of the above processes contains a significant amount of water, so that the coffee aroma components may only comprise 0.1 to 5 wt %, preferably 1 to 3 wt % of the coffee aroma fraction. Therefore, when added to aromatize a coffee extract, it will have a diluting effect on the coffee solids.

[0050] Preferably, a method of providing an aromatized coffee extract comprises:

[0051] (i) providing roast and ground coffee;

[0052] (ii) contacting the roast and ground coffee with water to form a coffee composition;

[0053] (ii) subjecting the coffee composition to an aroma separation step to recover a coffee aroma fraction and form a de-aromatized roast and ground coffee, wherein the aroma separation step recovers from 1% to 15% by weight of the coffee composition as the coffee aroma fraction;

[0054] (iii) subjecting the de-aroma roast and ground coffee to one or more water extraction steps to provide an intermediate coffee extract having from 35% to 70% by weight coffee solids;

[0055] (iv) adding the coffee aroma fraction to the intermediate coffee extract to form the aromatized coffee extract.

[0056] The roast and ground coffee preferably comprises, and optionally consists of, Arabica coffee beans, as they naturally contain higher levels of coffee oil. When coffee extracts are obtained using conventional methods, the roast and ground coffee will have an average particle size of approximately 2-3 mm. Preferably, the roast and ground coffee has an average particle size of 100 to 600 microns, as described below, as this increases the amount of oil released.

[0057] The de-aroma roast and ground coffee is subjected to one or more water extraction steps to provide an intermediate coffee extract having 35% to 70% by weight coffee solids (i.e., soluble coffee solids, coffee oils, and any insoluble coffee fraction), preferably 45% to 65% by weight coffee solids. Preferably, the solids level is high because, as mentioned above, the subsequent addition of coffee aroma has a dilutive effect. It should be noted that the extraction step will also involve some concentration steps, such as evaporation in an evaporator, to achieve these solids levels. Such steps are conventional in the extraction and spray drying processes used to obtain coffee powder.

[0058] Extraction steps are well known in the art, and preferably, the coffee is subjected to multiple steps, each step recovering a different fraction of the coffee extract. As each successive step involves higher temperatures, different coffee components are recovered and the overall yield is increased. By having successive steps, heat-sensitive components can be recovered separately from those components that require more harsh conditions to hydrolyze and become soluble coffee components.

[0059] A typical primary extraction may be performed at 140°C to 175°C, while a secondary extraction may be performed at 180°C to 205°C, with the option of performing further even higher extractions, such as from 205°C to 220°C.

[0060] Preferably, the aromatized coffee extract contains the coffee aroma fraction and the intermediate coffee extract in a weight ratio of coffee aroma fraction to intermediate coffee extract of 2:5 to 1:20. That is, the stripped aroma fraction is added to the intermediate coffee extract according to these weight ratios. As can be seen, this addition results in a significant reduction in solids content. For example, 2 parts of coffee aroma fraction (primarily water) added to 5 parts of an intermediate coffee extract at 70% solids will provide an aromatized coffee extract with approximately 50% coffee solids. More preferably, the aromatized coffee extract contains the coffee aroma fraction and the intermediate coffee extract in a weight ratio of coffee aroma fraction to intermediate coffee extract of 1:5 to 1:10.

[0061] More generally, the fraction of coffee aroma added back to the intermediate coffee extract will depend on the fraction of aroma recovered from the roast and ground coffee and water. Within a wider range of recovered aroma amounts (i.e., from 1% to 15% stripping by weight), the ratio of coffee aroma fraction to intermediate coffee extract is preferably from 1:40 to 30:40. Within an intermediate range of recovered aroma amounts (i.e., from 5% to 12% stripping by weight), the ratio of coffee aroma fraction to intermediate coffee extract is preferably from 5:40 to 24:40. Within a range of approximately 10% stripping by weight, the ratio of coffee aroma fraction to intermediate coffee extract is preferably from 10:40 to 20:40 (i.e., 1:4 to 1:2).

[0062] The coffee aroma fraction is highly desirable for aromatizing coffee extracts because it improves the sensory profile of the product's aroma. It has been found that providing a homogenization step allows a much larger portion of the aroma compounds in the aroma fraction to survive the spray-drying process, resulting in a product with a greatly improved aroma profile. Furthermore, it has been found that the fine distribution of the oil droplets improves the associated mouthfeel and beverage texture.

[0063] The preferred method for obtaining an aqueous coffee extract, described in PCT / EP2019 / 086859, will now be described in more detail. This method utilizes a novel extraction process that can radically alter the flavor and taste of instant coffee, while still relying solely on water extraction. The key parameters driving these changes are the use of a much finer grind size combined with lower extraction and hydrolysis temperatures, without compromising the process's yield.

[0064] One advantage of this process is that it can be carried out in a completely continuous manner. This saves on the cost and complexity of processing equipment. Another benefit is that it can be operated with lower amounts of water, which is of course desirable for the environment, and also saves a lot of energy when the aim is to provide a dry powder, as less water needs to be removed.

[0065] The process also uses lower temperatures than conventional temperatures in the initial heat treatment, which helps to restore more desirable coffee flavors. This ensures that high yields are maintained, as the method has a higher temperature secondary heat treatment.

[0066] Furthermore, the process provides a coffee product with improved flavor and taste. In particular, the flavor and taste are surprisingly different from products obtained by conventional methods, resulting in a beverage with a richer mouthfeel and better flavor profile.

[0067] The method comprises a number of steps. It will be apparent that a number of these steps must be performed sequentially on a given portion of the material being processed, but it will also be appreciated that these steps may be performed as part of a continuous process, batchwise, or a combination of both.

[0068] According to the first step (step (i)), roasted and ground coffee having an average particle size of 100 to 600 microns, preferably 200 to 600 microns, is provided. The roasted and ground coffee is obtained from coffee beans that have been roasted and ground using techniques recognized in the art. The average particle size is D50, as measured using a Helos dry laser diffractometer under standard measurement conditions.

[0069] The grind size used here is much finer than that employed in conventional coffee extraction processes, which typically use a particle size of approximately 2 mm. The fine particle size allows for the formation of a pumpable slurry while increasing the surface area available for extraction. Furthermore, the energy required to grind the coffee to this size is not excessive and does not result in undesirable thermal degradation of the coffee beans during grinding.

[0070] Preferably, the roast and ground coffee is ground to an average particle size of 200 to 400 microns, more preferably 250 to 350 microns, which is within the range of particle sizes conventionally ground for producing espresso coffee beverages. This is particularly advantageous because, as explained below, less water needs to be added to prepare the slurry. Furthermore, below 250 microns, filtration becomes more difficult and less efficient. At particle sizes below 100 microns, particles can clog filters.

[0071] In another embodiment, the roast and ground coffee preferably has an average particle size of 400 to 600 microns. This is particularly advantageous for preparing liquid coffee concentrates. This is because for liquid products, it is better to have larger particles to reduce the oil content in the product, as oil causes crema instability in liquids. Larger particle sizes release less oil into the resulting extract.

[0072] According to another step (step (ii)), the roasted and ground coffee is mixed with water to form a first slurry containing 15% to 30% by weight of coffee solids. That is, water is added to the coffee beans at a certain ratio so that the coffee beans provide 15% to 30% by weight of the entire mixture, preferably 20% to 25% by weight. The coffee solids include insoluble coffee solids and soluble coffee solids, some of which will dissolve in the added water. This level of water provides a pumpable slurry. The amount of water required for the pumpable slurry depends on the size of the grind used: coarser grinds require more water to achieve pumpability. In the case of a grind size of about 250 microns, dilution can be easily used to achieve, for example, 25% solids. In the case of a grind size of about 100 microns, dilution can be easily used to achieve, for example, 30% solids. However, at a particle size of 400 to 600 microns, it is desirable to add more water, such as to achieve 15% solids.

[0073] According to a further step (step (iii)), the first slurry is passed through an aroma separation step to recover the coffee aroma fraction and form a de-aromatized slurry. Aroma separation systems are well known in the art of soluble coffee production. An exemplary processing unit is a rotating cone operable to extract aroma. This involves introducing steam into the slurry, which strips aroma from the coffee, which can be recovered as an aqueous aroma stream that is stored for later use. Step (iii) can be performed under vacuum.

[0074] The temperature of the slurry during the aroma separation step can be adjusted as needed, but is typically in the range of 70°C to 100°C (e.g., 90°C to 100°C) at the start of the process. This heat treatment (i.e., aroma separation) is preferably carried out for 10 seconds to 2 hours, 1 minute to 25 minutes, preferably 1 minute to 5 minutes. In alternative embodiments, the duration may be 15 minutes to 25 minutes. Of course, if this is the aroma recovery technology employed, the temperature can be affected by the addition of steam. The aroma separation can be carried out under vacuum.

[0075] The temperature of the slurry can be raised before the aroma separation step by heating the added water before or after forming the slurry. The temperature change can be achieved using heat recovered from other steps of the process, such as by using a conventional heat exchanger. Preferably, the water in step (ii) is at a temperature of 80°C to 100°C when mixed with the coffee. This is because adding hot water is cheaper than heating it together with the coffee beans or using steam to heat the slurry. If the water is not heated before mixing with the coffee, the water is added at a temperature between 15°C and 40°C and the subsequent slurry is heated to 80°C to 100°C. This option has the advantage of improved process simplicity.

[0076] At this point in the process, after step (iii), the slurry comprises soluble coffee solids, de-aromatised insoluble coffee solids and water.

[0077] According to a further step (step (A)), the deodorized slurry is conveyed to a first filtration device at a temperature of 90°C to 150°C, preferably 90°C to 120°C and more preferably 90°C to 100°C to form a first coffee extract and a first filter cake. In a preferred embodiment, the deodorized slurry is conveyed to the first filtration device at a temperature of 140°C to 150°C. Thus, the process separates the majority of the soluble coffee solids and water from the insoluble coffee solids. The first filtration device can be one of several known filtration systems, including settling tanks, filters and centrifuges. Filters are preferred because they have the ability to process efficiently and continuously and the versatility to handle fine particles. It is most desirable to use a continuous filtration device. This allows for efficient separation of insoluble solids from water with a recovery of soluble solids greater than 90%.

[0078] The coffee solids in the filter cake may be washed or pressed to increase the extraction of soluble coffee solids. The first coffee extract (which is a concentrated coffee liquor) may be stored for later use in the process or added directly to a later step in the process in a continuous manner.

[0079] According to a further step (step (B)), water is added to the first filter cake to form a reconstituted slurry having at least 12% by weight of coffee solids. That is, water is added in an amount necessary to produce a slurry that typically has a slightly lower solids level than in the first slurry formation step. Preferably, the reconstituted slurry formed in step (e) has a solids level of 12% to 30% by weight, more preferably 12% to 20% by weight. This solids level is selected to achieve the desired pumpability. Similarly, reconstitution can be achieved with heated water, if desired.

[0080] Preferably, the water in step (B) is at a temperature of 80 to 100°C. This is because adding hot water is cheaper and it also helps to achieve some of the temperatures required in subsequent steps. Heat can be recovered from other steps in the process.

[0081] According to a further step (step (C)), the reconstituted slurry is heat treated at a temperature of 150°C to 205°C, preferably 170°C to 205°C and more preferably 180°C to 205°C. Preferably, the heating is carried out under high pressure to improve the extraction yield. The preferred pressure is 2 bar to 30 bar, such as 15 bar. The heat treatment is preferably carried out for 5 minutes to 2 hours, preferably 5 minutes to 15 minutes, preferably 5 minutes to 10 minutes. In an alternative embodiment, the duration may be 15 minutes to 25 minutes. During this step, some of the insoluble coffee solids are hydrolyzed into soluble solids, which can then be recovered. This step can be carried out using a plug flow reactor.

[0082] At this point in the process, the slurry again contains soluble coffee solids, insoluble coffee solids and water. It can be subjected to a flash process where a pressure drop allows any unwanted aroma flavours to be removed.

[0083] According to a further step (step (D)), the heat-treated reconstituted slurry is passed to a second filtration device to form a second coffee extract and a second filter cake. The filtration device can be any of the filtration devices discussed above. This serves to separate the coffee liquor containing dissolved soluble coffee solids from the insoluble coffee solids. The second filter cake can be washed and / or pressed again to recover additional coffee extract. The second coffee extract typically has a lower soluble solids concentration than the first coffee extract.

[0084] The second coffee extract, which is a concentrated coffee liquor, may be stored for use later in the process.

[0085] According to a further step (step (E)), the first coffee extract and the second coffee extract are combined to form a third coffee extract. The two coffee extracts are typically combined by simple mixing to provide the third coffee extract.

[0086] According to a further step (step (F)), the third coffee extract is concentrated to form a fourth coffee extract having 35% to 70% coffee solids by weight, preferably 35% to 65% coffee solids, and more preferably 40% to 50% coffee solids by weight. When aroma is added in the subsequent step (v), a solids level of 55% to 60% after step (F) is preferred to allow dilution to achieve a useful final concentration. This provides a coffee extract suitable for use as a concentrate (i.e., flowable) or for use in a drying process to produce a dry product (i.e., with less water removed). Preferably, step (F) is performed in an evaporator unit.

[0087] According to a further step (step (v)), the coffee aroma fraction (from step (iii)) is added to a fourth coffee extract (also referred to herein as an intermediate coffee extract) to form an aromatized coffee extract, which is then homogenized and spray-dried in steps (b) and (c). This improves the flavor of the extract without compromising the solids level. The aroma is added after the concentration step to avoid limited aroma loss from the product. The resulting coffee extract preferably has a coffee solids content of 35% to 65% by weight, and preferably 45% to 65% by weight.

[0088] The coffee extract product is a soluble powder. That is, the method further comprises a step (c) of spray-drying the aromatized coffee extract to form a soluble powder. Preferably, the powder product has an average particle size of 200 to 3000 microns, more preferably 500 to 2000 microns. The product can be agglomerated in a spray dryer or fluidized bed, or by any other known technique, to adjust the particle size as desired.

[0089] The coffee solids remaining after step (D) can be processed as a waste stream and can be incinerated to provide energy for the process (such as for heating water). Alternatively, the second filter cake can be subjected to an additional high-temperature extraction process to obtain an additional coffee extract, which will be combined with the first and second coffee extracts in step (E) to form a third coffee extract. Suitable conditions for this additional high-temperature processing step are temperatures of 190°C to 215°C. The heat treatment is preferably carried out for 5 minutes to 2 hours, preferably 15 minutes to 25 minutes. This additional step can be carried out using a further set of slurry formation and filtration steps, or using conventional extraction techniques.

[0090] Generally speaking, this method involves the use of less water than conventional extraction methods. The use of high solids levels reduces the energy consumption of the associated concentration steps. The process also allows for efficient heat recycling between the different stages by adding water heated at different stages and heat that can be recovered from the product of the high-temperature extraction step.

[0091] Preferably, the method further comprises packaging the coffee extract product.

[0092] Preferably, the process also includes an agglomeration step to improve solubility and increase the particle size of the final product. This also avoids dust and powder problems.

[0093] According to a further aspect, there is provided a coffee extract product obtainable by the method described herein.

[0094] The finished instant coffee product exhibits an improved flavor with less process flavor and an improved flavor that is closer to freshly brewed coffee. Undesirable process acidity produced by processing at higher temperatures is also reduced.

[0095] According to a further aspect, there is provided a spray-dried coffee powder for forming a coffee beverage,

[0096] wherein the powder comprises particles comprising soluble coffee solids and insoluble coffee solids, the insoluble coffee solids comprising coffee oil and an insoluble coffee sediment fraction, the insoluble coffee sediment fraction being the non-oil portion of the insoluble coffee solids,

[0097] wherein the powder comprises at least 6% by weight of the insoluble coffee sediment fraction, the insoluble coffee sediment fraction comprising 1% by weight or less arabinose when analysed after acid hydrolysis,

[0098] wherein the powder comprises at least 0.8% by weight on a dry weight basis of coffee oil, and

[0099] wherein the particles exhibit less than 20 wt % surface coffee oils based on the total weight of coffee oils.

[0100] According to a further aspect, there is provided a spray-dried coffee powder for forming a coffee beverage,

[0101] wherein the powder comprises particles comprising soluble coffee solids and insoluble coffee solids, the insoluble coffee solids comprising coffee oil and an insoluble coffee sediment fraction, the insoluble coffee sediment fraction being the non-oil portion of the insoluble coffee solids,

[0102] wherein the powder comprises at least 6% by weight of the insoluble coffee sediment fraction, the insoluble coffee sediment fraction comprising 1% by weight or less arabinose when analysed after acid hydrolysis,

[0103] wherein the powder comprises at least 0.8% by weight on a dry weight basis of coffee oil, and

[0104] wherein the powder, when reconstituted in water, provides a particle size distribution of oil droplets with a D50 oil droplet size of less than 8 microns, less than 7 microns, more preferably less than 5 microns and most preferably less than 4 microns, such as from 1 micron to 7 microns and most preferably from 1 micron to 5 microns, more preferably from 2 microns to 4 microns, more preferably from 2.5 microns to 3.5 microns.

[0105] According to a further aspect, there is provided a spray-dried coffee powder for forming a coffee beverage,

[0106] wherein the powder comprises particles comprising soluble coffee solids and insoluble coffee solids, the insoluble coffee solids comprising coffee oil and an insoluble coffee sediment fraction, the insoluble coffee sediment fraction being the non-oil portion of the insoluble coffee solids,

[0107] wherein the powder comprises at least 6% by weight of the insoluble coffee sediment fraction, the insoluble coffee sediment fraction comprising 1% by weight or less arabinose when analysed after acid hydrolysis,

[0108] wherein the powder comprises at least 0.8% by weight on a dry weight basis of coffee oil, and

[0109] The powder can be obtained by spray-drying an aromatized aqueous coffee extract. The aromatized aqueous coffee extract refers to an aqueous coffee extract comprising a coffee aroma fraction and a coffee extract, wherein the coffee aroma fraction is obtained by stripping 5 to 12 wt. %, preferably about 10 wt. %, of freshly roasted and ground coffee beans, and wherein the aromatized coffee extract contains the coffee aroma fraction and the coffee extract in a weight ratio of coffee aroma fraction to coffee extract of 2:5 to 1:20. Fresh means that they have not been previously extracted.

[0110] The following discussion of preferred features applies to all aspects of the present invention relating to spray-dried coffee powder. In addition, these aspects can be freely combined with other aspects discussed herein.

[0111] The inventors have discovered that the above-described process produces a unique spray-dried coffee powder. Specifically, the product has an improved aroma and mouthfeel compared to conventional commercially available coffee products. The presence of a high oil content and subsequent homogenization has been found to provide an improved mouthfeel and better preserve the aroma components returned to the coffee during the aroma reintroduction step. This allows for the provision of new and improved soluble coffee products that rival the performance of premium freeze-dried coffee.

[0112] The product is characterized, in part, by (i) comprising at least 6% by weight of an insoluble coffee sediment fraction that, when analyzed after acid hydrolysis, contains 1% by weight or less arabinose; and (ii) comprising at least 0.8% by weight, on a dry weight basis, of coffee oil. These characteristics are characteristic of the pulp extraction process described herein. In particular, the very fine grind size of the extracted coffee provides a higher oil yield. Furthermore, the fine particle size and pulping steps result in the incorporation of a sediment fraction having a characteristic level of arabinose, indicating partial extraction of insoluble material during the coffee processing steps. Thus, a soluble coffee product is a product inherently produced by the method.

[0113] Furthermore, the provision of low surface oil is a result of a stable oil-in-water emulsion obtained by the homogenization step. Thus, the product has unique properties of the products obtained therefrom that are not observed in other processing methods. Preferably, the product of this further aspect is obtainable by the method described herein.

[0114] When combined with the method of PCT / EP2019 / 086859 and as discussed herein, the process results in the presence of an insoluble coffee sediment fraction within the product and higher levels of oil as a direct result of the process, without the need for separate addition of oil or addition of roast and ground coffee. Thus, the process is an elegant approach to providing an improved product from roast and ground coffee at high yields.

[0115] This insoluble coffee fraction superficially resembles the roast and ground coffee additive often added to coffee products to improve the flavor of conventional coffee extracts. However, the insoluble coffee sediment fraction is present in the product as a direct result of the process, and no additional step of supplementing the coffee extract with roast and ground coffee is required. Thus, the products of the present invention can be characterized by the presence of an insoluble coffee sediment fraction, which distinguishes them from commercially available coffee products that have not been supplemented with additional roast and ground coffee.

[0116] Surprisingly, the inventors have found that the insoluble coffee sediment fraction obtained as a direct result of the process is less likely to settle out of the extract than a post-added roast and ground coffee extract. This is observed in the final beverage, where significantly less sediment or scum is deposited on the walls of the container after the beverage has been swirled in the container.

[0117] The insoluble coffee sediment fraction obtained using the above process further differs from the insoluble coffee sediment fraction observed for coffee with conventionally added roast and ground coffee additives. This is because this fraction has undergone the coffee extraction process and has been exposed to a heated aqueous environment, which alters the carbohydrate balance in the insoluble coffee material. Therefore, the products of the present invention can be characterized by carbohydrate analysis of the insoluble coffee sediment fraction, as distinguished from commercially available coffee products that have been supplemented with additional roast and ground coffee.

[0118] Additionally, the process produces a higher oil fraction in the coffee product. This is a result of the finer coffee particle grind size used in the process. Because the finer grind exposes more coffee surface area for extraction, it is understood that a greater amount of oil is released during the extraction process. Thus, the product of the present invention can be characterized by the presence of a higher oil fraction, which distinguishes it from commercially available coffee products obtained through conventional extraction processes.

[0119] The insoluble coffee sediment fraction is the sediment obtained using the repeated centrifugation process described herein. It represents the solid material (not oil) present in the product that is insoluble in water.

[0120] The composition preferably comprises 7.5 to 15 wt% of an insoluble coffee sediment fraction. Such amounts of insoluble coffee sediment fraction provide a well-balanced aroma without having excessive amounts of insoluble material which may adversely affect mouthfeel and may cause undesirable sediment.

[0121] Preferably, the insoluble coffee sediment fraction comprises from 0.5 to 1 wt% arabinose when analysed after acid hydrolysis.

[0122] Preferably, the insoluble coffee sediment fraction comprises less than 5 wt% galactose, preferably from 2 to 4 wt% galactose when analysed after acid hydrolysis.

[0123] Preferably, the instant coffee composition comprises at least 1% by weight coffee oil, preferably 1.5% to 5% by weight coffee oil, and more preferably 2% to 4% by weight, on a dry weight basis. Increasing the oil level improves the mouthfeel of the product. Higher oil levels improve mouthfeel while also increasing the weight yield obtained and used from the coffee beans. The oil obtained as a result of the process has been found to be well distributed within the extract, contributing to an improved mouthfeel without creating an undesirable oily film in the final beverage.

[0124] Preferably, the particles exhibit less than 20% surface coffee oil by weight, based on the total weight of the coffee oil. The surface oil can be determined by solvent extraction techniques. Exemplary solvent extraction techniques are discussed in the Examples below. Preferably, the particles exhibit less than 15% surface coffee oil by weight, and preferably less than 10% by weight, based on the total weight of the coffee oil. Without wishing to be bound by theory, it is believed that this low level of surface oil is a direct result of the homogenization step described herein. In particular, by providing a finer and better dispersed oil-in-water emulsion throughout the extract prior to spray drying, the emulsion is less disturbed by the spray drying process. As a result, the oil is evenly distributed throughout the particles, rather than agglomerated on the surface. It is believed that this contributes to improved product performance because the fine oil structure can be retained upon reconstitution in the beverage medium (i.e., hot water at 80°C to 95°C).

[0125] In particular, the particles preferably exhibit less than 20 wt% of surface coffee oil based on the total weight of the coffee oil, such as less than 19 wt%, such as less than 18 wt%, such as less than 17 wt%, such as less than 16 wt%, such as less than 15 wt%, such as less than 14 wt%, such as less than 13 wt%, such as less than 12 wt%, such as less than 11 wt%, such as less than 10 wt%, such as less than 9 wt%, such as less than 8 wt%, such as less than 7 wt%, such as less than 6 wt%, such as less than 5 wt%, such as less than 4 wt%, such as less than 3 wt%, such as less than 2 wt%, such as less than 1 wt%.

[0126] Preferably, the spray-dried coffee particles, when reconstituted in water, provide a particle size distribution of oil droplets with a D50 oil droplet size of less than 8 microns, less than 7 microns, more preferably less than 5 microns and most preferably less than 4 microns, such as from 1 micron to 7 microns and most preferably from 1 micron to 5 microns, more preferably from 2 microns to 4 microns, more preferably from 2.5 microns to 3.5 microns. The particle size can be determined using confocal laser scanning microscopy (such as using a Zeiss Z2M machine). The sample can be fluorescently labeled and imaged using confocal laser scanning microscopy (CLSM) using the lipid staining dye BODIPY TM The oil droplets are located within the emulsion. Imaging can be performed using a 488 nm laser and a bandpass filter from 490 nm to 555 nm, with the fat regions false-colored green. Image analysis can be used to successfully measure particle size results, ignoring non-spherical or brown coffee particles. A representative sample of at least 1,000 oil droplets should be measured. Samples were observed at a standard beverage concentration of approximately 1.5% solids by weight.

[0127] Preferably, the instant coffee composition has a unimodal particle size distribution when dissolved and analyzed by wet laser diffraction at a concentration of 1.5% by weight (solids). This distinguishes it from products in which roasted and ground coffee is added as a supplement to a soluble coffee powder (typically in a coffee extract prior to drying). Specifically, conventional grinding techniques that crack the coffee beans typically produce a bimodal distribution based on the cracking of the beans, with the lower peak resulting from the finest cell wall fragments. In contrast, the coffee particles retained after the method of the present invention, or in a conventional extract emerging from a percolation column, have a bimodal distribution.

[0128] Preferably, the instant coffee composition also has a D50 of less than 10 microns, preferably between 2.5 microns and 7.5 microns, when dissolved, using the same particle measurement. This fine particle size reflects the effect on the extract obtained from the coffee process described above. In fact, the observed particle size distribution is unusual in that the D90 is typically greater than 30 microns, reflecting a broad particle size distribution.

[0129] The composition consists of coffee. That is, the coffee composition does not contain any non-coffee components or additives (such as emulsifiers or dairy ingredients). However, as will be understood, the spray-dried coffee powder can be mixed with other non-coffee components such as sugar or milk powder to provide a final composite product, such as a three-in-one mix.

[0130] Quantification and analysis of the insoluble coffee sediment fraction requires separation of the insoluble coffee solids from the soluble coffee solids. In order to facilitate this evaluation of a liquid coffee product, it is necessary to dry the product into a powder so that the same analysis can be performed.

[0131] In order to separate and quantify the insoluble coffee sediment fraction (also referred to as sediment), 30 grams of a given coffee sample (dry powder) was added to 70 grams of boiling water and shaken for 2 minutes. The sample was then centrifuged at 10,000 g for 15 minutes. After centrifugation, the supernatant was decanted and the sediment was redissolved with 70 grams of boiling water, shaken for 2 minutes, and then centrifuged again under the same conditions as above. This washing process was repeated 3 times for a total of four centrifugation steps. The sediment from the final wash was then freeze-dried and the sediment percentage was then related to the 30 g starting sample (e.g., 1.8 g sediment represented a 6% by weight insoluble coffee sediment fraction). Before any analysis was performed, the dried sediment sample was homogenized by simple stirring.

[0132] Given the method used to analyze the insoluble coffee sediment fraction, the fraction does not include any coffee oils that may be present, even though these would be considered insoluble, as the oils would readily separate during the centrifugation step.

[0133] To determine the carbohydrate content of the separated insoluble coffee sediment fraction, total carbohydrate analysis was performed using high-performance anion exchange pulsed amperometric detection (HPAEC-PAD) according to ISO 11292-1995. The sample was prepared by mixing the separated sediment with 50 ml of 1 M HCl and shaking the sample at 95°C for 150 minutes. Monosaccharide quantification was typically performed by analyzing external monosaccharide standards.

[0134] To determine the particle size distribution of instant coffee products, a Malvern Mastersizer 3000 with a Hydro MV cell was used for particle size distribution analysis. 1.5 g of sample (± 0.0005 g) was made up to 100 g (± 0.05 g) with deionized water boiled at 100°C, stirred for 60 seconds, cooled slightly, and added dropwise to a Malvern cell to achieve approximately 10% haze. Three readings were averaged. Similarly, to facilitate this evaluation of liquid coffee products, it was necessary to dry the product into a powder so that the same analysis could be performed.

[0135] To determine the oil content, a sample of the product is evaluated using a Soxtec H6 (if the product is a liquid coffee concentrate, it is first dried). 2g of the sample is mixed with petroleum ether 40-60, boiled for 2 hours, and then rinsed for approximately 0.5 hours. The resulting condensate is then heated to recover the solvent. Assessing oil levels in this manner is well known in the art.

[0136] In some embodiments, the instant coffee composition of the present invention can be blended with conventional spray-dried coffee obtained by known methods. For example, the product may contain 10% to 100% (such as 20% to 50%) of the coffee described herein, blended with the remainder being conventional coffee. While this is readily achievable for liquid products, soluble products can be formed from mixed liquid extracts or from dry mixtures of different powdered products. This may be advantageous in situations where the mouthfeel and flavor benefits of the present invention are to be mitigated to provide a more conventional beverage experience.

[0137] According to a preferred embodiment, there is provided a method for producing coffee powder, the method comprising:

[0138] (a) providing roast and ground coffee having an average particle size of 100 microns to 600 microns;

[0139] (b) mixing the roast and ground coffee with water to form a first slurry containing 15% to 30% by weight coffee solids,

[0140] (c) passing the first slurry through an aroma separation step to recover a coffee aroma fraction and form a de-aromatized slurry;

[0141] (d) conveying the deodorized slurry to a first filtration device at a temperature of 90° C. to 150° C. to form a first coffee extract and a first filter cake;

[0142] (e) adding water to the first filter cake to form a reconstituted slurry having at least 12% by weight coffee solids;

[0143] (f) heat treating the reconstituted slurry at a temperature of 150° C. to 205° C.;

[0144] (g) then passing the heat-treated reconstituted slurry to a second filtration device to form a second coffee extract and a second filter cake;

[0145] (h) combining the first coffee extract and the second coffee extract to form a third coffee extract;

[0146] (i) concentrating the third coffee extract to form a fourth coffee extract having from 35% to 70% by weight coffee solids;

[0147] (j) adding the coffee aroma fraction to the fourth coffee extract to form an aqueous coffee extract comprising 30% to 55% by weight of soluble coffee solids and 1% to 10% by weight of oil, preferably 2% to 5% by weight of oil, wherein the aqueous coffee extract consists of water and coffee-derived components;

[0148] (k) subjecting the aqueous coffee extract to a two-stage homogenization process, wherein the first stage is carried out at 200 to 1000 bar and the second stage is carried out at 10 to 100 bar, to provide a homogenized coffee extract;

[0149] (1) spray drying the homogenized coffee extract to form coffee powder.

[0150] According to a preferred embodiment, there is provided a method for producing coffee powder, the method comprising:

[0151] (a) providing roast and ground coffee having an average particle size of 100 microns to 600 microns;

[0152] (b) mixing the roast and ground coffee with water to form a first slurry containing 15% to 30% by weight coffee solids,

[0153] (c) passing the first slurry through an aroma separation step to recover a coffee aroma fraction and form a de-aromatized slurry, wherein the aroma separation step recovers from 1% to 15% by weight of the coffee composition as the coffee aroma fraction, preferably from 8% to 12% by weight and most preferably about 10% by weight of the coffee composition as the coffee aroma fraction;

[0154] (d) conveying the deodorized slurry to a first filtration device at a temperature of 90° C. to 150° C. to form a first coffee extract and a first filter cake;

[0155] (e) adding water to the first filter cake to form a reconstituted slurry having at least 12% by weight coffee solids;

[0156] (f) heat treating the reconstituted slurry at a temperature of 150° C. to 205° C.;

[0157] (g) then passing the heat-treated reconstituted slurry to a second filtration device to form a second coffee extract and a second filter cake;

[0158] (h) combining the first coffee extract and the second coffee extract to form a third coffee extract;

[0159] (i) concentrating the third coffee extract to form a fourth coffee extract having from 35% to 70% by weight coffee solids;

[0160] (j) adding the coffee aroma fraction to the fourth coffee extract to form an aqueous coffee extract comprising 30 to 55 wt% soluble coffee solids and 1 to 10 wt% oil, preferably 2 to 5 wt% oil, wherein the aqueous coffee extract consists of water and coffee-derived components, and wherein the aromatized coffee extract contains the coffee aroma fraction and the intermediate coffee extract in a weight ratio of coffee aroma fraction to intermediate coffee extract of 2:5 to 1 :20, preferably 1 :10 to 3:10 and most preferably about 1 :5;

[0161] (k) subjecting the aqueous coffee extract to a two-stage homogenization process, wherein the first stage is carried out at 200 to 1000 bar and the second stage is carried out at 10 to 100 bar, to provide a homogenized coffee extract;

[0162] (1) spray drying the homogenized coffee extract to form coffee powder.

[0163] These preferred embodiments are freely combinable with all further features of the first aspect.

[0164] The invention will now be further described with reference to the accompanying drawings, in which:

[0165] · Figure 1 A flow chart showing the steps of the present invention is shown.

[0166] like Figure 1 As shown in , the method for manufacturing a coffee extract product comprises a number of steps.

[0167] In step (a), roast and ground coffee 2 having an average particle size of 100 to 600 microns, preferably 200 to 600 microns is provided. Within this range, larger sizes favor liquid extract products, while smaller sizes favor dry soluble coffee products.

[0168] In step (b), roast and ground coffee is mixed with water 5 to form a first slurry 10 containing 15% to 30% by weight coffee solids. Water 5 is added at a temperature of 80° C. to 100° C., and preferably 90° C. to 95° C. The solids level is determined by the particle size, as a minimum amount of water 5 is required to obtain a pumpable slurry 10. The larger the particle size, the more water 5 (lower solids) is required to achieve a pumpable slurry 10.

[0169] In step (c), the first slurry 10 is passed through an aroma separation step to recover a coffee aroma fraction 15 and form a de-aroma slurry 20. A typical process for this method involves adding steam 21 to the pumpable slurry 10, wherein the steam is processed in a rotating cone treatment unit. The recovered aroma fraction 15 is approximately 10% by weight of the first slurry 10, resulting in a de-aroma slurry 20 of 90% by weight of the slurry 10.

[0170] In step (d), the deodorized slurry 20 is passed to a first filtration device at a temperature of 90°C to 150°C, such as 90°C to 100°C, to form a first coffee extract 25 and a first filter cake 30. The temperature may be maintained from the previous step or may be further increased to increase the extraction yield. The filter cake 30 may be washed and pressed to obtain the maximum possible amount of soluble coffee solids.

[0171] In step (e), water 5 is added to the first filter cake 30 to form a reconstituted slurry 35 having at least 12% by weight coffee solids. The water 5 is preferably hot, and there may be mechanical agitation to break up the first filter cake 30. The amount of water required to reconstitute the slurry tends to be higher than the amount of water required in step (b).

[0172] In step (f), the reconstituted slurry 35 is heat treated at a temperature of 150° C. to 205° C., such as 180° C. to 205° C., to form a heat-treated reconstituted slurry 40. That is, it is pumped through a heat treatment unit, such as a plug flow reactor. The residence time in the heat treatment is typically at least 5 minutes to ensure good extraction.

[0173] In step (g), the heat-treated reconstituted slurry 40 is passed to a second filtration device to form a second coffee extract 45 and a second filter cake 50. The second filter cake 50 may be washed and pressed to obtain the maximum possible amount of soluble coffee solids. The temperature in this step may be maintained from the previous step, or may be reduced, such as to a temperature of 80°C to 100°C, as heat is recovered for use in step (b).

[0174] The second filter cake 50 may then be combusted in step M to generate heat for the process, or may be subjected to a further high temperature extraction step M to obtain further coffee extract 52 .

[0175] In step (h), the first coffee extract 25 and the second coffee extract 45 are combined to form a third coffee extract 55. Other aqueous coffee extracts, such as further coffee extract 52, may also be added in this step.

[0176] In step (i), the third coffee extract 55 is concentrated to form a fourth coffee extract 60 having from 35% to 70% by weight coffee solids, such as from 35% to 60% by weight coffee solids.

[0177] In step (j), the coffee aroma fraction 15 is added to the fourth coffee extract 60 (intermediate coffee extract) to form an aromatized coffee extract 65. The aroma fraction 15 is added in an amount of 1 part to 5 parts of the fourth coffee extract 60.

[0178] The aromatized coffee extract 65 is homogenized in step k in a two-step homogenizer 70 to form a homogenized coffee extract 75. The two-step homogenizer 70 performs the first step at a pressure of 700 bar and the second step at a pressure of 50 bar.

[0179] The homogenized coffee extract 75 is spray dried in step (L) to form a dried coffee product 80 .

[0180] The invention will now be further described with respect to the following non-limiting examples.

[0181] Example 1

[0182] Roasted whole beans were ground to between 200 and 400 μm in a 3-stage roller mill.

[0183] Roast and ground coffee was slurried with water at a ratio of 25% coffee to 75% water at 20-30°C.

[0184] The slurry is fed forward into a heat exchanger and heated to 95°C before moving into a rotating cone where the aroma is stripped from the slurry.

[0185] After exiting the spinning cone, the slurry was fed forward through a heat exchanger, raising the temperature to between 120°C and 150°C for 2 to 5 minutes.

[0186] The slurry is then fed into a filter to separate the coffee liquor from the grinds.The grinds are then subjected to 2 further washing steps at 130°C to 150°C to remove additional solids.

[0187] The grind is then re-slurried with fresh water at a rate of 12% to 17% solids. The resulting slurry is fed forward to the hydrolysis step where it is heated to between 180°C and 205°C (185°C) and held for between 5 and 20 minutes.

[0188] The resulting slurry is then cooled to below 100°C and then passed through a second filtration step, repeating the separation and washing of the first separation step.

[0189] The coffee extracts obtained from each filtration step are combined and concentrated. The aroma compounds stripped from the first slurry are then added to the mixture.

[0190] The completely combined three components were then subjected to homogenization at 200 bar and then 40 bar. The homogenized extract was spray-dried using conventional techniques to obtain a soluble coffee powder.

[0191] Example 2

[0192] Arabica and / or Robusta coffee beans were roasted and ground using a 3-stage roller mill to an average particle size of 300 um. The ground coffee was then slurried with water at a ratio of 25% coffee to 75% water at 20°C to 25°C.

[0193] The slurry is fed forward into a heat exchanger and heated to 70°C before moving into a rotating cone where the aroma is stripped from the slurry.

[0194] The slurry was then fed into a filter at a temperature of 95°C to separate the coffee liquor from the grounds. The grounds were then subjected to 2 further washing steps to remove additional solids.

[0195] The grind was then re-slurried with fresh water at a ratio of 12% to 17% solids. The resulting slurry was fed forward to the plug flow reactor (hydrolysis step) where it was heated to 170°C and held for 5 to 10 minutes.

[0196] The resulting slurry is then cooled to below 100°C and then passed through a second filtration step, repeating the separation and washing of the first separation step.

[0197] The coffee extracts obtained from each filtration step are combined and concentrated. The aroma compounds stripped from the first slurry are then added to the mixture.

[0198] The completely combined three components were then subjected to homogenization at 200 bar and then 40 bar. The homogenized extract was spray-dried using conventional techniques to obtain a soluble coffee powder.

[0199] The product of this example was found to have more body / mouthfeel than products produced using current technology.

[0200] Example 3

[0201] Coffee slurry was prepared as described in Example 1.

[0202] The slurry is fed forward into a heat exchanger and heated to 95°C before moving into a rotating cone where the aroma is stripped from the slurry.

[0203] After exiting the spinning cone, the slurry was fed forward through a heat exchanger, raising the temperature to between 145°C and 150°C for 4 to 5 minutes.

[0204] The slurry was then fed into a filter to separate the coffee liquor from the grinds. The grinds were then subjected to 2 further washing steps at 140°C to remove additional solids.

[0205] The slurry is then fed into a filter, which separates the coffee liquid from the grounds.

[0206] The grind was then re-slurried with fresh water at a ratio of 12% to 17% solids. The resulting slurry was fed forward to the plug flow reactor (hydrolysis step) where it was heated to 200°C and held for 7 to 10 minutes.

[0207] The resulting slurry is then cooled to below 100°C and then passed through a second filtration step, repeating the separation and washing of the first separation step.

[0208] The coffee extracts obtained from each filtration step are combined and concentrated. The aroma compounds stripped from the first slurry are then added to the mixture.

[0209] The completely combined three components were then subjected to homogenization at 200 bar and then 40 bar. The homogenized extract was spray-dried using conventional techniques to obtain a soluble coffee powder.

[0210] The product of this example was found to have more body / mouthfeel than products produced using current technology.

[0211] Example 4

[0212] Arabica and / or Robusta coffee beans were roasted and ground using a 3-stage roller mill to an average particle size of 400 um. The ground coffee was then slurried with water at a ratio of 15% coffee to 85% water at 20°C to 25°C.

[0213] The rest of the process was carried out as in Example 1.

[0214] The resulting product had a lower oil level than the product of Example 1.

[0215] Oil droplet assessment

[0216] The size of the oil droplets in coffee extracts produced according to the method in P1 (see Example 1) was studied before and after homogenization at different stage 1 pressures. In each case, stage 2 was at 40 bar. This time period indicates the stability after homogenization.

[0217] As shown in the data, the higher the pressure, the more stable the oil droplets are over time. Also, the higher the pressure, the smaller the D50 size and the narrower the distribution range (D90-D10).

[0218] The concentration of the extract also has an impact on size and stability. A dilute concentrate is only 10% solids by weight, while a concentrated extract is 50% solids by weight.

[0219] This shows that for the non-homogenized high oil extract, the D50 value is about 9.6 microns, while for the homogenized high oil extract, the D50 is much lower, about 3.2 and 2.9. It should be noted that the dilute extract data falls outside the claimed solids range and has too much water to be spray dried, but still supports the same trend.

[0220]

[0221]

[0222] Additional embodiments

[0223] The following examples were carried out using the method of PCT / EP2019 / 086859 (hereinafter P1 ) and are provided at least as comparative evidence of the properties of prior art compositions.

[0224] Samples obtained by the process described herein were evaluated in comparison with a range of commercially available soluble coffee products. From the comprehensive testing, it can be seen that the products obtained by this process are novel and can be easily distinguished from products obtained by conventional processes.

[0225] Oil content

[0226]

[0227] *Bean identity of the compared products is based on educated guesswork

[0228] Examples 7, 8, 9 and 10 were produced according to the method described in P1. Examples 1 to 6 are commercially available products, whereas 2 and 4 are products supplemented with an added roast and ground coffee additive (designated "whole bean instant" in the table).

[0229] It is generally understood that the oil level in Robusta coffee beans is lower than that in Arabica coffee beans. This is reflected in the generally lower oil levels in products containing Robusta coffee beans, including Example 9 of the present invention. Sample 10 is a dark Brazilian coffee known for its high oil level.

[0230] As can be seen, low oil levels are present in the pure instant coffees (i.e., Samples 1, 3, 5, and 6), which have not been supplemented with the roast and ground coffee additive. The oil levels in Samples 2 and 4 are slightly higher due to the oil content of the roast and ground coffee additive, with Sample 2 containing approximately 5% roast and ground coffee and Sample 4 containing more roast and ground coffee.

[0231] Samples 7, 8, and 10 contained high levels of oil due to the fine grinding of the roasted coffee in a process that released more oil into the extract.

[0232] It can be seen that conventional soluble coffee products do not contain significant levels of oil. In fact, it is speculated that the oil levels observed for some of these products were subsequently added to the surface of the dry powder to improve its flavor.

[0233] The only prior art products containing high oil levels were the result of adding roast and ground coffee additives to the product. In contrast, the process described in P1 achieved high levels of oil even for Robusta coffee bean products.

[0234] Sediment levels

[0235] Sediment levels are determined by taking 30 grams of a given coffee sample, adding it to 70 grams of boiling water and shaking it for 2 minutes. The sample is then centrifuged at 10,000 g for 15 minutes. After centrifugation, the supernatant is decanted and the sediment is re-dissolved in 70 grams of boiling water, shaken for 2 minutes, and then centrifuged again under the same conditions as above. This washing process is repeated three times, for a total of four centrifugation steps. The sediment from the final wash is then freeze-dried, and the sediment percentage is then related to the 30 grams starting sample (e.g., 1.8 grams of sediment represents a 6% by weight insoluble coffee sediment fraction).

[0236] sample Sediment (weight %) 1 <![CDATA[l'Or Intense TM ]]> 5.2 2 <![CDATA[Kenco Rich TM ]]> 4.7 3 <![CDATA[Carte Noir TM ]]> 3.8 4 <![CDATA[Kenco Milicano Americano TM ]]> 11.5 5 <![CDATA[NescaféGold TM ]]> 4.4 6 <![CDATA[NescaféAzera Americano TM ]]> 9.3 7 P1 Robusta 11.9 8 P1 Colombian Arabica 7.8 9 P1 Centrals Arabica 9.2

[0237] Examples 7, 8 and 9 have been produced according to the method described in PI. Examples 1 to 6 are commercially available products, whereas 4, 5 and 6 are products supplemented with added roast and ground coffee additives.

[0238] It can be seen that all commercially available instant coffee products have a certain level of insoluble coffee sediment fraction. This is expected to be small fragments of coffee cell walls that pass through the extraction system into the coffee extract. The level of insoluble coffee sediment fraction generally increases for those products supplemented with added roast and ground coffee additives.

[0239] It can be seen that the products produced according to the process described in P1 all have a significantly higher level of insoluble coffee sediment fraction than the instant coffee product which has not been supplemented with the added roast and ground coffee additive.

[0240] Particle size distribution

[0241]

[0242] Examples 7, 8 and 9 have been produced according to the method described in PI. Examples 1 to 6 are commercially available products, whereas 4, 5 and 6 are products supplemented with added roast and ground coffee additives.

[0243] Sedimentation quantitative methods with multiple centrifugation steps allow the recovery of large quantities of very fine particles.

[0244] The particle size distribution was measured with a Malvern 3000 having been prepared after preparing a 1.5% hot brew of the dry product (eg 3 g of dry product in 200 ml of hot water).

[0245] Three types of sediments can be distinguished:

[0246] Category 1 (L'Or Intense TM 、Kenco Rich TM and Carte Noir TM ) :

[0247] Unimodal distribution D10: <1.5 μm and D90: <15 μm

[0248] Relatively low amount of sediment <5.5 wt%

[0249] Very small particle sizes (such as low D90) may reflect how these particles have escaped from the extraction column into the extract, or mannan that has been deposited in the evaporator.

[0250] Category 2: (Kenco Milicano TM 、Nescafé Gold TM and Azera TM ) is obviously different from category 1 and category 3

[0251] Bimodal distribution (2 peaks): Peak 1 between 1 μm and 10 μm and Peak 2 between 10 μm and 100 μm.

[0252] Category 3: Samples of the present invention

[0253] Unimodal distribution, but broader than Class 1: D10: >1.0 μm and D90: >15 μm, and the amount of sediment is relatively high, such as >7.5 wt%.

[0254] Carbohydrate analysis

[0255] The analysis is of monosaccharides after acid hydrolysis.

[0256]

[0257] Examples 7, 8 and 9 have been produced according to the method described in PI. Examples 1 to 6 are commercially available products, whereas 4, 5 and 6 are products supplemented with added roast and ground coffee additives.

[0258] It can be seen that the insoluble coffee sediment fraction of the P1 product has a level of arabinose that is generally similar to the arabinose level of the soluble coffee product that has not been supplemented with roast and ground coffee. In general, it also has lower levels of galactose than the soluble coffee product that has been supplemented with roast and ground coffee.

[0259] Without wishing to be bound by theory, it is believed that the high levels of arabinose in the supplemented product are a result of the presence of unextracted coffee material. In contrast, the levels are lower for the product of P1, reflecting the fact that arabinose has been extracted into the soluble coffee fraction by the process of P1.

[0260] sensory testing

[0261] Two prototypes of the P1 product were combined with a product from the current technology at a ratio of 30 (POI):70 (current product). These were then tested in a group with an additional sample of 100% current technology product. The three samples were presented to a sensory panel, who were then asked to pair the products based on similarity / difference with the third sample.

[0262] Results show that even at just a 30% level in a blend with the current product, the prototype is perceived as stickier, drier, and powderier—all attributes that contribute to mouthfeel and consistency. These levels correlate directly with tribological data. More oil means more lubrication, which means a smoother mouthfeel and consistency. The effects are shown in Figure 3.

[0263] Collapse temperature

[0264] The crystalline product has a well-defined "eutectic" freezing / melting point, which is known as its collapse temperature. When freeze-drying concentrated coffee extract, the extract is heated under vacuum from an initial freezing temperature of about -50°C. This allows the water content to sublime away. The heating rate depends on the extract, and there is a collapse temperature above which the product will melt back and be affected. The temperature and pressure can then be increased in subsequent cycles until signs of collapse or melt back are observed, indicating that the product is too hot. The inventors were surprised to find that the collapse temperature of several samples of P1 was higher than that of their standard coffee product.

[0265] Rheological properties of samples

[0266] 1 <![CDATA[Alta Rica TM ]]> 2 <![CDATA[Nescafe Gold Blend TM ]]> 3 <![CDATA[Kenco Really Rich TM ]]> 4 <![CDATA[Milicano TM ]]> 5 <![CDATA[Percol TM ]]> 6 <![CDATA[Kenco Really Rich TM ]]> 7 NGC Colombia P1 8 NGC Central P1 9 NGC Robusta P1 10 NGC Brazil P1

[0267] Samples were prepared with 10 g of coffee dissolved in 40 g of water at 85° C. Complete dissolution was achieved by stirring with a 25 mm stir bar at 150 rpm for 2 minutes.

[0268] The rheometer was used to analyze the flow rate of the rheometer at a speed between 0.01 and 1000 s. -1 These samples were tested in a simple shear sweep between shear rates of 1.5 and 2.5 with a sample volume of 8 ml and a circulating bath set to -4° C. The samples were studied at temperatures of 20° C. and 65° C. and concentrations of 1.5 wt % and 20 wt %.

[0269] The data were then fitted to the Quemada model, which develops insights into fluid rheology based on the theory of internal structural unit (SU) suspensions.

[0270] In concentrated systems, single particles and small flocs can form larger and larger groups, the size of which will depend on the applied shear rate.

[0271] Therefore, since viscosity (η) is a function of structure (η=f(s)), and this structure depends on the level of shear applied (since increasing the shear rate will only serve to disperse the macro- and mesostructure of the flocs into individual subunits), viscosity can be expressed in terms of packing fraction / compactness, since the more compact the SU, the higher the packing and therefore the more structure (viscosity) will be present.

[0272] This is because the compactness of SU will contribute to the levelness of the structure;

[0273]

[0274]

[0275] where η is the viscosity and Φ is a measure of compactness.

[0276] It has been noted that at 20 wt% (i.e. concentrated samples) at 65°C (close to the consumption temperature), sample 4 (Milicano) and samples 7 to 10 have significantly higher η0. This means that from a microstructural point of view, at lower shear rates (1s -1 At lower shear rates (these lower shear rates represent those during chewing and reflect the mouthfeel), these samples have more structure relative to the other samples. This means that at these lower shear rates, the compactness of their structural units is higher, i.e., better packing of the structural units.

[0277] The tribology of the samples was also observed. "Tribology is the science and engineering of interacting surfaces in relative motion. It includes the study and application of the principles of friction, lubrication, and wear." Therefore, the parameters to be noted are μ 最大 , which represents the maximum friction observed for each sample. Since lubrication indicates the mouthfeel here and the higher μ 最大 A lower lubricity is indicated, which should translate into a lower mouthfeel.

[0278] It is observed that at 65°C (consumption temperature), samples 7, 8, and 10 have significantly lower μ 最大 , indicating lower friction and therefore higher mouthfeel. The exception was Sample 9 (Robusta blend) which had a lower oil content.

[0279] Measuring the surface oil content of soluble coffee powder

[0280] The samples were extracted by Soxhlet extraction and the oil content was weighed.

[0281] equipment

[0282] Soxtherm Gerhardt Extraction Unit

[0283] Multistat Soxterm service unit

[0284] Oven / circulation oven @105℃±2℃

[0285] analytical balance

[0286] Desiccator with silica gel

[0287] Materials and consumables

[0288] Gerhardt extraction beaker G_Nr.13-0050

[0289] Coffee filter (size 4)

[0290] Extraction sleeve, 33mmx80mm (S&S 603)

[0291] cotton wool

[0292] Reagents

[0293] Hexane 40℃-60℃ boiling range, AR grade (also known as hexane)

[0294] Sample analysis

[0295] Place the extraction beaker in a drying oven at 103°C for 1 hour

[0296] Remove from oven and allow to cool in a desiccator.

[0297] • Weigh the extraction beaker to 4 decimal places (M1).

[0298] • Weigh 5 grams of dry sample (M2) into a No. 4 coffee filter and fold it together. Place the filter into the cannula, leaving a 5 mm space for the cotton wool plug on top.

[0299] Carefully place the cotton plug on top.

[0300] Place the extraction cannula into the weighed extraction beaker

[0301] Fill the extraction beaker with 150ml of n-hexane

[0302] Place the extraction beaker with the contents in the Soxtherm device

[0303] The extraction was performed with the help of the Multi-Stat program base unit (15 min extraction boiling, 30 min (total analysis time 1 h 17 min).

[0304] After extraction, remove the extraction cannula.

[0305] • Gently blow out the residual hexane in the extraction beaker with compressed air and further evaporate in an oven at 105°C for 1 hour.

[0306] After cooling, weigh the extraction beaker (M3) containing the obtained oil

[0307] Expression of results

[0308]

[0309] Unless otherwise indicated, all percentages herein are by weight.

[0310] Although preferred embodiments of the present invention have been described in detail herein, those skilled in the art will appreciate that changes may be made therein without departing from the scope of the invention or the appended claims.

Claims

1. A method for producing coffee powder, the method comprising: a) providing an aqueous coffee extract by extracting roast and ground coffee having an average particle size of less than 600 microns, the aqueous coffee extract comprising from 30% to 55% by weight soluble coffee solids and from 1% to 10% by weight oil, wherein the aqueous coffee extract consists of water and components derived from coffee; b) subjecting the aqueous coffee extract to a two-stage homogenization process, wherein the first stage is carried out at 200 to 1000 bar and the second stage is carried out at 10 to 100 bar, to provide a homogenized coffee extract; c) spray drying the homogenized coffee extract; The method does not include any step of adding coffee oil to the aqueous coffee extract.

2. The method of claim 1, wherein the aqueous coffee extract comprises 1.5% to 5% by weight of coffee oil.

3. The method of claim 1 , wherein the aqueous coffee extract is an aromatized coffee extract and is provided by: (i) providing roast and ground coffee; (ii) contacting the roast and ground coffee with water to form a coffee composition; (iii) subjecting the coffee composition to an aroma separation step to recover a coffee aroma fraction and form a de-aromatized roast and ground coffee, wherein the aroma separation step recovers from 1% to 15% by weight of the coffee composition as the coffee aroma fraction; (iv) subjecting the de-aromatized roast and ground coffee to one or more water extraction steps to provide an intermediate coffee extract having from 35% to 70% by weight coffee solids; (v) adding the coffee aroma fraction to the intermediate coffee extract to form the aromatized coffee extract.

4. The method according to claim 3, wherein the aromatized coffee extract contains the coffee aroma fraction and the intermediate coffee extract in a weight ratio of coffee aroma fraction to intermediate coffee extract of 2:5 to 1:

20.

5. The method according to claim 3, wherein: said roast and ground coffee provided in step (i) having an average particle size of 100 to 600 microns, Step (ii) comprises mixing the roast and ground coffee with water to form a first slurry containing 15% to 30% by weight coffee solids, and wherein the deodorized roast and ground coffee is a deodorized slurry.

6. The method according to claim 5, wherein step (iii) comprises: (A) conveying the de-aromatized slurry to a first filtration device at a temperature of 90° C. to 150° C. to form a first coffee extract and a first filter cake; (B) adding water to the first filter cake to form a reconstituted slurry having at least 12% by weight coffee solids; (C) heat treating the reconstituted slurry at a temperature of 150° C. to 205° C.; (D) then conveying the heat-treated reconstituted slurry to a second filtration device to form a second coffee extract and a second filter cake; (E) combining the first coffee extract and the second coffee extract to form a third coffee extract; and (F) concentrating the third coffee extract to form the intermediate coffee extract.

7. The process according to claim 6, wherein the water in step (ii) and / or step (B) is at a temperature of 80 to 100°C.

8. The method of claim 6, wherein the reconstituted slurry formed in step (B) has a solids content of 12 wt% to 30 wt%.

9. The method of claim 6, wherein the second filter cake is subjected to a further high temperature extraction process to obtain a further coffee extract to be combined with the first coffee extract and the second coffee extract in step (E) to form the third coffee extract, wherein The temperature of the high temperature extraction process is in the range of 190°C to 215°C.

10. The method of claim 1, further comprising packaging the coffee grounds.

11. The method of claim 1 , wherein the method is a continuous process.

12. A spray-dried coffee powder for forming a coffee beverage, wherein the powder comprises particles comprising soluble coffee solids and insoluble coffee solids, the insoluble coffee solids comprising coffee oil and an insoluble coffee sediment fraction, the insoluble coffee sediment fraction being the non-oil portion of the insoluble coffee solids, wherein said powder comprises at least 6% by weight of said insoluble coffee sediment fraction, said insoluble coffee sediment fraction comprising 1% by weight or less arabinose when analysed after acid hydrolysis, wherein the powder comprises at least 0.8 wt% coffee oil on a dry weight basis, and wherein the particles exhibit less than 20 wt % surface coffee oils based on the total weight of coffee oils.

13. The spray-dried coffee powder of claim 12, wherein the powder has a D50 oil droplet size of less than 7 microns when reconstituted in water.

14. A spray-dried coffee powder according to claim 12 or claim 13, wherein the powder comprises 7.5 to 15 wt% of the insoluble coffee sediment fraction.

15. The spray-dried coffee powder of claim 12, wherein the insoluble coffee sediment fraction comprises 0.5 to 1 wt% arabinose when analyzed after acid hydrolysis.

16. The spray-dried coffee powder of claim 12, wherein the powder comprises from 1 to 5 wt% coffee oils on a dry weight basis and / or wherein the particles exhibit less than 15 wt% surface coffee oils based on the total weight of coffee oils.

17. The spray-dried coffee powder according to claim 12 obtainable by the method according to claim 1.

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