BEVERAGE PREPARATION DEVICES, APPARATUS AND METHODS

Abstract

A beverage extraction device comprising an upper chamber and a lower chamber separated by a filter; wherein the upper chamber comprises a perimeter wall and an inlet and the lower chamber comprises a perimeter wall and an outlet; and wherein the perimeter wall of the upper chamber adjacent to the filter tapers inwardly, towards the filter, by no more than 10 degrees and the perimeter wall of the lower chamber tapers inwardly from adjacent to or proximal to the filter.

Claims

1. A beverage extraction device comprising an upper chamber and a lower chamber separated by a filter; wherein the upper chamber comprises a perimeter wall and an inlet and the lower chamber comprises a perimeter wall and an outlet; and wherein the perimeter wall of the upper chamber adjacent to the filter tapers inwardly, towards the filter, by no more than 10 degrees and the perimeter wall of the lower chamber tapers inwardly from adjacent to or proximal to the filter.

2. The beverage extraction device of claim 1 wherein the maximum diameter of the tapering perimeter wall adjacent to the filter or the tapering section of the lower chamber proximal to the filter is between 25% and 95% the diameter of the perimeter wall of the upper chamber adjacent to the filter.

3. The beverage extraction device of claim 1 wherein the lower chamber tapers inwardly from proximal to the filter and wherein there is a short length of non-tapering perimeter wall of the lower chamber, such that the tapering section of the perimeter wall commences no more than 8 mm below the filter.

4. The beverage extraction device of claim 1 wherein the lower chamber of the beverage extraction device comprises an unobstructed fluid path from the filter to the outlet.

5. The beverage extraction device of claim 1 wherein the volume of the upper chamber is no more than 500 ml.

6. The beverage extraction device of claim 1 wherein the perimeter wall of the upper chamber is non-tapering.

7. The beverage extraction device of claim 1 wherein the perimeter wall of the lower chamber tapers inwardly from adjacent to the filter.

8. A method of preparing a beverage comprising, providing the beverage extraction device of claim 1 and comprising steps of: a. addition of an extractable beverage material to the upper chamber of the beverage extraction device; b. addition of water to the extractable beverage material in the upper chamber to create a beverage extract; and c. collection of the beverage extract from the lower chamber of the beverage extraction device.

9. The method of claim 8 wherein the volume of water added in step b) is between 100 and 400 ml.

10. The method of claim 9 wherein the water is added at a rate of at least 1 ml/sec.

11. The method of claim 8 wherein the total extraction time is between 2 and 5 minutes.

12. A beverage preparation apparatus comprising: the beverage extraction device of claim 1; a water heating device; and a water conduit, and wherein the water conduit is arranged, in use, to deliver water heated by the water heating device into the upper chamber of the beverage extraction device via the inlet.

13. The apparatus of claim 12 wherein the apparatus is a drip filter appliance.

14. A method of preparing a beverage comprising, using the beverage preparation apparatus of claim 12 and comprising steps of: a. Addition of an extractable beverage material to the upper chamber of the beverage extraction device; b. Delivering water heated by the water heating device through the water conduit and to the upper chamber of the beverage extraction device to create a beverage extract; and c. Collection of the beverage extract from the lower chamber of the beverage extraction device.

15. The method of claim 14 wherein the total extraction time is between 2 and 5 minutes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0089] In order that the invention may be more clearly understood embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, of which:

[0090] FIG. 1 is a side cross-sectional view through a first embodiment of a beverage preparation device of the invention;

[0091] FIG. 2 is a side view of a first embodiment of a beverage preparation apparatus of the invention;

[0092] FIG. 3 is a side cross-sectional view through a second embodiment of a beverage preparation device of the invention comprising a lower chamber perimeter wall with non-tapering section; and

[0093] FIG. 4 is a side cross-sectional view through a third embodiment of a beverage preparation device of the invention comprising an upper chamber perimeter wall with a slight taper.

[0094] With reference to FIG. 1, a first embodiment of a beverage extraction device (2) of the invention, comprises an upper chamber (4) and a lower chamber (14) separated by a support in the form of a porous mesh screen (10) and a paper filter (12). The upper chamber (4) comprises a perimeter wall (6). The lower chamber comprises a perimeter wall (16) and an outlet (18).

[0095] The upper chamber perimeter wall (6) is non-tapering adjacent to the mesh screen (10). The mesh screen (10) is adjacent to and on top of the paper filter (12). In other embodiments, not shown, the vertical order of the mesh screen (10) and paper filter (12) may be reversed. The mesh screen (10) has a mesh size of 0.85 mm and thread diameter of 0.5 mm. The paper filter (12) has thickness of 1.1 mm, a low flow resistance and a diameter of less than the diameter of the upper chamber (4) (approximately 80-90% of the diameter of the upper chamber (4)). The lower chamber (14) is adjacent to the paper filter (12). The perimeter wall of the lower chamber (16) tapers down away from the paper filter (12) at an angle of 45° to a minimum diameter of 15 mm over a length of 6.1 mm to meet the outlet (18). The total length from the top of the filter paper (12) to the end of the outlet (18) is 17 mm. The lower chamber (14) has a volume of 6 ml and the upper chamber (4) a volume of 350 ml.

[0096] The tapering lower chamber wall (16) has a greatest diameter, adjacent to the filter (10) and mesh screen (12), of approximately 40% of the diameter of the upper chamber (4).

[0097] The outlet (18) comprises a circular cross-sectional tube, having a diameter approximately 60-70% of the largest diameter of the lower chamber wall (16).

[0098] With reference to FIG. 2, where like numbers represent like components vis-à-vis FIG. 1, a beverage preparation apparatus (50) comprises a beverage extraction device (2), a means for supplying water, in the form of a water tank (56), a beverage preparation apparatus body containing a water heater (58), a water outlet (54) and a beverage container (53). The water tank (56), the water heater (58) and the water outlet (54) are connected together by pipework (not shown). The water outlet (54) is located adjacent to the upper chamber of the beverage extraction device (2) and the beverage container is located below the outlet (18) of the beverage extraction device (2).

[0099] With reference to FIG. 3, where like numbers represent like components vis-à-vis FIG. 1, a beverage extraction device (20) comprises an upper chamber (4) and a lower chamber (14) separated by a support in the form of a mesh screen (10) and a paper filter (12). The upper chamber (4) comprises a perimeter wall (6). The lower chamber comprises an upper non-tapering perimeter wall section (15) adjacent to the filter (12) and mesh (10); a tapering lower perimeter wall section (16) and an outlet (18). The beverage extraction device is largely similar to the beverage extraction device (2) of FIG. 1; but differs by addition of the upper non-tapering perimeter wall section (15) of the lower chamber adjacent to the filter (12) and mesh screen (10) that acts to separate the tapering lower perimeter wall section (16) from the filter (12) by 5 mm; and the filter (12) extends across the full diameter of the upper chamber (4) and upper chamber perimeter wall (6).

[0100] With reference to FIG. 4, in which like numbers represent like components vis-à-vis FIG. 1, a beverage extraction device (30), comprises an upper chamber (4) and a lower chamber (14) separated by a support in the form of a mesh screen (10) and a paper filter (12). The upper chamber (4) comprises a perimeter wall (6). The lower chamber comprises a perimeter wall (16) and an outlet (18). The beverage extraction device is largely similar to the beverage extraction device (2) of FIG. 1; but differs by the perimeter wall of the upper chamber (6), having a taper of approximately 9° towards the filter (12).

Example 1—Preparation of a Beverage Using a Beverage Extraction Device of the Invention

[0101] A beverage was prepared using the beverage extraction device (2) of FIG. 1 by the following steps: [0102] a) The upper chamber (4) was loaded with 12 g of roast and ground coffee (Aroma Rood®, produced by Jacobs Douwe Egberts), the device (2) fitted with a Senseo® chocolate filter paper, code UPC05A and the device (2) supported above a beverage container; [0103] b) 234 ml of water heated to 80-100° C. was then added at a rate of 2.6 ml/sec to the upper chamber at a steady rate over 1 minute 30 seconds. During this time the volume of water in the upper chamber (4) of the beverage extraction device (2) built to a maximum i.e. the flow rate of heated water into the beverage extraction device (2) was the same as the flow rate of the beverage extract from the outlet (18) of the beverage extraction device (2); and [0104] c) After the addition of water stopped, the beverage extraction device (2) was then left to drain until the beverage extract stopped flowing from the outlet (18). Approximately 3 minutes 15 seconds after the start of water addition to the device.

[0105] The device (2) of the embodiment of FIG. 1 is configured such that, in use, the flow rate of beverage extract is between 1 ml/s and 1.6 ml/s throughout the extraction process. The flow rate of extract from the device was slower than the flow rate of water into the device.

[0106] The flow rate through the beverage extraction device (2) is largely determined by the combination of resistances between the filter (12), mesh (10) and geometry of the lower chamber (14). The major contributors to the overall flow resistance through the device (2) of Example 1 are: [0107] From the upper chamber (4), the beverage extract undergoes a portion of horizontal flow through the filter (12) and mesh (10) in order to reach the smaller diameter lower chamber (14), maximising the resistance provided by the low resistance filter paper (12). [0108] Upon traversing through the mesh (10) and filter paper (12) the beverage extract forms a meniscus under the mesh (10), held by surface tension and supported by the geometry of the shoulders provided by the tapering perimeter wall (or tapering section of the perimeter wall) of the lower chamber (16). This meniscus provides additional flow resistance below the upper chamber. [0109] The outlet (18) is configured (with a non-tapering perimeter wall) to provide little or no resistance to the flow of beverage extract.

[0110] There is also a contribution to overall resistance from the coffee bed and a slow increase in resistance due to the clogging of filter pores by coffee particles during extraction, but this is a far lower proportion of the total resistance through the device than in devices of the prior art, such as in Example 2, below.

[0111] By configuring the majority of the flow resistance through the beverage extraction device (2) to be present below the coffee bed and top surface of the filter (12), the device (2) of Example 1 benefits from a consistent flow rate throughout the extraction rather than the steadily decreasing flow rate of the prior art, such as Example 2, where the flow rate through the extraction device (2) is largely determined by the compacting coffee bed and clogging top surface of the filter (12).

[0112] The configuration of the upper chamber (6) with a substantially parallel, non-tapering circumferential wall and the difference in flow rate into and out of the extraction device enabled the creation of convection and turbulence in the upper chamber of the extraction device such that the coffee particles formed at least a partial suspension in the water during the preparation of the beverage—enhancing the extraction of the slow extracting coffee fractions.

[0113] Further, the geometry of the upper chamber a sufficiently high fill height for a given volume of water, compared to Example 2 below, to further enhance the convection; a lower deposition of coffee grounds on the sides of the container, compared to Example 2 below; an even deposition of coffee grounds in the coffee bed upon draining the extraction chamber, facilitating even extraction; a small footprint; a smaller liquid surface to facilitate lower heat loss during the preparation of the beverage extract.

Example 2 (Control)—Preparation of a Control Beverage Using a Drip Filter Appliance of the Prior Art

[0114] A control beverage was prepared using a prior art Excellent 10SN drip filter appliance (50) manufactured by Douwe Egberts. The drip filter appliance includes a brew basket in the form of a frusto-conical plastic chamber tapering to a narrow outlet. The brew basket is arranged in use to receive a 3-dimensional filter liner by the following steps: [0115] a) A filter liner and 12 g of roast and ground coffee were added to the brew basket of the appliance; [0116] b) Cold water was added to the water reservoir (58) of the appliance (50); [0117] c) The appliance was switched on to provide a steady flow of 234 ml of hot water at a rate of 2.6 ml/sec over 1 minute 30 seconds to the brew basket of the appliance (50) and the beverage extract collected below.

Comparison of the Results of Example 1 and Control Example 2

Beverage Extract Flow Rate:

[0118] The beverage extract flow rate in Example 1 was 1.2 ml/sec over the 3 minute 15 second beverage preparation time and varied very little between the initial rate of 1.6 ml/sec and the final rate of 1 ml/sec. In contrast the beverage extract flow in control Example 2 slowed significantly during the extraction process as the main influencers of resistance through the device were hampered by compaction of the coffee bed and the pores of the filter paper were clogged with coffee particles.

Beverage Extract Flavour Profiles:

[0119] The beverage extracts obtained in Example 1 and control Example 2 were put to a trained professional sensory panel for analysis of select flavour attributes and the results are shown in Table 1.

TABLE-US-00001 TABLE 1 Comparison of sensory attributes between beverages produced in example 1 and control example 2 Flavour attribute Example 1 Control Example 2 Light Taste 50 39 Bitter Taste 35 44 Sweet Taste 27 19 Fresh Taste 40 26 Dry Mouthfeel 23 33

[0120] The data shows that the flavour obtained in the extract of Example 1 shows improved Light Taste, Sweet Taste, Fresh Taste and reduced Bitter Taste and Dry Mouthfeel over the beverage extract produced in the control Example 2. This sensory data supports the conclusion that there is an optimum extractable material/water contact time to be reached in such beverage extraction devices and that the extractable material/water contact time enabled by the beverage extraction devices (2) of the present invention yields an improved beverage over those produced by prior art devices.

[0121] The sensory evaluation confirmed an optimised balance of extraction between fast and slow extracting fractions of coffee compared in Example 1 compared to Example 2.

Further Examples of Embodiments of the Invention

Example 3: A Beverage Extract Prepared by a Beverage Preparation Apparatus of the Invention

[0122] A beverage extract was prepared by loading the beverage extraction device (2) of FIG. 1 into an Excellent 10SN drip filter appliance (50) manufactured by Douwe Egberts to create the beverage preparation apparatus (50) of FIG. 2 by the following steps: [0123] a) 12 g of roast and ground coffee was added to the upper chamber (6) of the beverage extraction device (2); [0124] b) Cold water was added to the water reservoir (58) of the appliance (50); [0125] c) The appliance (50) was switched on to provide a steady flow of 234 ml of hot water at a rate of 2.6 ml/sec over 1 minute 30 seconds to the extraction device (2) attached to the appliance (50) and the beverage extract collected from the outlet (18) of the lower chamber (14) of the beverage extraction device (2).

[0126] The beverage extract flow rate was identical to that of Example 1 and the beverage had the same profile under sensory analysis as that of Example 1.

[0127] Alternative of Beverage Extraction Devices of the Invention

[0128] With reference to FIG. 1, when in use, the beverage extraction device (2) provides a fluid flow path for the beverage extract from upper chamber (4) to lower chamber (12). The route of the fluid flow path from upper chamber (4) to outlet (18), the filter paper (12) and/or mesh (10) properties and the meniscus size and shape formed below the filter (12) and mesh (10) have an impact on the flow resistance and therefore extractable material/water contact time and quality of the extracted beverage. The meniscus size and shape can be adjusted by variation in the maximum diameter of lower chamber perimeter wall (16). The tapering perimeter wall (16) of the lower chamber (14) of device (2) of FIG. 1 has the preferred maximum diameter of 40-50% the diameter of the perimeter wall of the upper chamber (6) whereas, embodiments of a device of the invention (not shown) exist that benefit from at least one of the advantages of FIG. 1 where the maximum diameter of the tapering perimeter wall (16) of the lower chamber of the device (2) of FIG. 1 is between one quarter to three quarters the diameter of the perimeter wall of the upper chamber (6). Further, the meniscus size and shape can be adjusted by variation in the angle of the taper of the perimeter wall of the lower chamber (16). In further embodiments of a beverage extraction device (2) of the invention (not shown) the taper of the perimeter wall of the lower chamber (16) of FIGS. 1-4 may be between 35° and 55°, for example, and maintain at least one of the benefits of the invention.

[0129] FIGS. 3 and 4 show examples of alternative beverage extraction devices (20) and (30). Each exhibits sufficient flow resistance below the coffee bed and top surface of the filter to secure the benefits associated with the beverage extraction device (2) of Example 1.

[0130] Further to variations of FIG. 1, the meniscus formation below the filter (12) and its impact on flow resistance through the device can also be manipulated by spacing the tapered perimeter wall of the lower chamber (16) away from the filter. With reference to FIG. 3, the short upper non-tapering perimeter wall section (15) of the lower chamber (14) provides additional volume to the lower chamber (16) without significantly hindering the formation of the coffee extract meniscus below the filter (12) and the resistance to flow through the device (20) this provides when in use. The lower non-tapering perimeter wall section (15) of the lower chamber (16) is spaced 5 mm from the filter (12).

[0131] With reference to FIG. 4, the small taper in the perimeter wall (6) of the upper chamber (6) provides an increase in volume to the upper chamber (6) and a larger opening at the top of the perimeter wall (6) for ease of adding beverage material into the upper chamber (4). No negative impact was seen to the benefits associated with the device of FIG. 1 by the inclusion of a small taper to the circumferential wall of the upper chamber. A turbulent, convection of the coffee/water suspension was still created, there was little deposition of coffee grounds on the circumferential wall, the coffee bed was deposited evenly across the filter and the heat loss from the upper chamber was largely unaffected.

[0132] The above embodiments are described by way of example only. Many variations are possible without departing from the scope of the invention as defined in the appended claims.