Process and plant

Abstract

The present disclosure relates to a plant and process for extracting alcohol from a feed beverage. The process includes: forming a pool of the feed beverage; and delivering a gas into the pool to form bubbles that ascend in the feed beverage and pass into a headspace over the beverage, the bubbles forming a liquid / gas interface with the feed beverage such that alcohol in the feed beverage is transferred into the bubbles and carried into the headspace, thereby extracting alcohol from the feed beverage and producing a reduced alcohol beverage.

Description

PROCESS AND PLANTRELATED APPLICATION

[0001] The present application claims priority to Australian provisional application number 2024903299 filed 14 October 2024, the full contents of which are hereby incorporated into the present specification.FIELD

[0002] The present invention relates to a plant and process for extracting alcohol from a beverage. The plant and process are suitable for extracting alcohol from the beverage to produce a reduced alcohol beverage.BACKGROUND

[0003] Traditional processes for extracting alcohol from beverages often involve heating the beverage to volatize alcohol from the beverage. However, this can adversely affect the flavour and aroma of the beverage. This problem has to some extent been address by heating the beverage under a vacuum to reduce the effective boiling temperature of alcohol. This may reduce the impact the processes have on flavour and other desirable attributes but still involves high energy inputs and is a relatively complex process. Other brewing or distillation methods including reducing the initial sugar content in order to produce beverages containing less alcohol from the outset. However, both of these approaches can still adversely affect the flavour and other desired attributes of the beverage.

[0004] Therefore, there is a need for an alternative process and plant for producing a beverage having a lowered alcohol content.SUMMARY

[0005] An embodiment of the present invention relates a process for extracting alcohol from a feed beverage, in which the process includes: forming a pool of the feed beverage; and delivering a gas into the pool to form bubbles that ascend in the feed beverage and pass into a headspace over the beverage, the bubbles forming a I iquid / gas interface with the feed beverage such that alcohol in the feed beverage is transferred into the bubbles and carried into the headspace, thereby extracting alcohol from the feed beverage and producing a reduced alcohol beverage.1P0533WO

[0006] An embodiment of the present invention relates a process for extracting alcohol from a feed beverage, in which the process includes: providing the feed beverage; and delivering a gas into the feed beverage so as to form bubbles that ascend in the feed beverage, the bubbles forming a I iquid / gas interface with the feed beverage such that alcohol in the feed beverage is transferred into the bubbles and separating the bubbles from the feed beverage, thereby extracting alcohol from the feed beverage and producing a reduced alcohol beverage.

[0007] Without wanting to be bound by theory, we believe that alcohol is extracted from the feed beverage by being volatilized into a gas phase of the bubbles, and in turn into the headspace.

[0008] The gas may be any suitable gas including any one or a combination of carbon dioxide gas, nitrogen gas, air, oxygen gas, or an inert gas such as helium and argon.

[0009] The feed beverage may be any solution available from brewing or distilling processes, including a final distil, or an intermediate distil that are to undergo further processing stages. In other words, the feed beverage and the reduced alcohol beverage is, or will end up being, a consumable beverage.

[0010] The process may extract alcohol from the feed beverage so that the reduced alcohol beverage is less than an initial alcohol content of the feed beverage.

[0011] The feed beverage may have any initial alcohol content prior to being treated by the process. The initial alcohol content will typically be determined by the brewing or distillation process in which the beverage is made. Typically, distilled spirits have an initial alcohol content of 30+ vol %, wine 12+ vol%, and beer 3+ vol%, and the low alcohol beverage may be less than 3 vol% or typically 0.5 vol% (alcohol by volume ABV).

[0012] In one example, the initial alcohol content of the feed beverage may have a high alcohol content such as 80 vol%, 75 vol%, 70 vol%, 65 vol% or 60 vol% alcohol of the beverage. The alcohol content of the reduced alcohol beverage produced by the process may range from 50 to 0.5vol%. That is to say, the reduced alcohol content may be as low as3.0 vol%, 2.5 vol%, 2.0 vol%, 1.5 vol %. 1.0 vol %, or 0.5 vol %, or preferably from 3 vol% to only trace amounts.

[0013] In one example, the initial alcohol content of the feed beverage may have an alcohol content such as 22 vol %, 18 vol %, 14 vol %, 12 vol %, 11 vol% or 10 vol % alcohol, that is to say to range from 22 vol% to 9 vol%, and the process may extract alcohol from the feed beverage so that the reduced2P0533WOalcohol beverage is less than the initial alcohol content. For instance the alcohol content of the reduced alcohol beverage may range from 10 to 0.5 vol %. That is to say, alcohol content of the reduced alcohol beverage may be as low as 3.0 vol %, or preferably 2.5 vol%, or preferably 2.0 vol%, or preferably 1.5 vol %, or preferably 1.0 vol %, or or preferably 0.5 vol %, or preferably only trace amounts.

[0014] In other examples, the initial alcohol content of the feed beverage may be 6.5, 6.0, 5.5, 5.0, or 4.5 vol % alcohol of the feed beverage, and the process may extract alcohol from the feed beverage so that the reduced alcohol beverage is less than the initial alcohol content. For instance, the alcohol content of the reduced alcohol beverage may range from 4.9 to 0.5 vol %. That is to say, the reduced alcohol content may be as low as 3.0 vol%, or preferably 2.5 vol%, or preferably 2.0 vol%, or preferably 1.5 vol %, or preferably 1.0 vol %, or preferably 0.5 vol %, or preferably only trace amounts.

[0015] In one example, the alcohol content of the reduced alcohol beverage may be in the range of 40 to 100% less than the alcohol content of the feed beverage. In another example, the alcohol content of the reduced alcohol beverage may be in the range of the 55.9 to 81.4% less than the alcohol content of the feed beverage. In another example, the alcohol content of the reduced alcohol beverage may be in the range of the 39.4 to 79.9 % less than the alcohol content of the feed beverage.

[0016] In one example, the process may be carried out without either one or a combination of the gas or the feed beverage being heated. That is to say, the gas and / or feed beverage may have ambient temperatures in the ranging from 5 to 25°C. This has the advantage of conserving and retaining flavours, aromas and other inherent properties of the feed beverage.

[0017] In another example, the process may include controlling the temperature of the gas delivered into the pool to a temperature ranging from 25 to 80°C.

[0018] In another example, the gas delivered may have a temperature above 80°C.

[0019] In another example, the process may include controlling the temperature of the feed beverage to a temperature ranging from 25 to 80°C.

[0020] In another example, the beverage may have a temperature above 80°C.

[0021] The process may be carried out at any suitable pressure. For example, the headspace may be a pressure ranging from 0.9 to 1.5 bar absolute. In one example, the process may be carried out with the headspace below atmospheric pressure. In another example, the process may include3P0533WOcontrolling the pressure in the headspace at a pressure below atmospheric pressure. In another example, the process may be carried out with the headspace at atmospheric pressure. The process may include controlling the pressure in the headspace at atmospheric pressure. In another example, the process may be carried out with the headspace above the atmospheric pressure. The process may include controlling the pressure in the headspace to a pressure above atmospheric pressure. An advantage in having the headspace below atmospheric pressure is that the boiling point of alcohol reduces which may increase the rate of volatilization of alcohol into the bubbles. It is expected that by reducing pressure in the headspace, the amount of alcohol per volume of gas bubbling in the beverage will increase.

[0022] The pool may have any suitable depth. In one example, the process may include controlling the depth of the pool. In one example, the process may include controlling the depth of the pool as a function of a flow rate of the gas delivered to the pool. In another example, the process may include controlling and / or varying the depth of the pool as function of the size of the bubbles of gas in the pool.

[0023] For example, the process may include controlling the depth of the pool to a range from 5 to 25cm, or preferably from 5 to 20cm, or preferably from 5 to 15 cm, or preferably from 8 to 13 cm, or preferably approximately 10 cm.

[0024] The process may include forming the bubbles by passing the gas through a porous substrate located in the pool.

[0025] Suitably the porous substrate is located on the floor of the pool, so that the bubbles ascend the depth of the pool. The porous substrate may include a gas permeable material including a frit located in the pool.

[0026] The bubbles may have any suitable diameter. The diameter of the bubbles will have an impact on the rate of transfer of alcohol into the bubbles. For instance, as the bubbles reduce in the size, a ratio of the surface area to the volume of the bubbles will increase, facilitating transfer of the alcohol into the vapour phase of the bubble per volume of the bubbles. In addition, the size of the bubble has an impact on the rate at which the bubbles ascend in the feed beverage and the stability of the bubbles. In any event, bubbles in the beverage may have a tendency to coalesce in the feed beverage.

[0027] In an example, a majority of the bubbles may have a diameter ranging from 0.1mm to 7.0 mm. In another example, a majority of the bubbles may have a diameter ranging from 1.0 mm to 3.0 mm.4P0533WO

[0028] In an example, greater than 90% of the bubbles may have a diameter ranging from 0.1mm to 7.0 mm. In another example, greater than 90% of the bubbles may have a diameter ranging from 1.0 mm to 3.0 mm.

[0029] In an example, the bubbles being formed may have a diameter ranging from 0.1mm to 7.0 mm. In another example, the bubbles being formed may have a diameter ranging from 1.0 mm to 3.0 mm.

[0030] Bubbles smaller than 0.1mm in diameter, including micro and nanobubbles can be formed. For example by vibrations and shaking. Microbubbles and nanobubbles may coalesce as that rise in the pool.

[0031] The process may include controlling a ratio of the volume of the bubbles in the pool to the total volume of the pool, include the bubbles and the feed beverage in the pool. In one example, the volume of the bubbles ranges from 10% to 60% of the total volume of the pool, including the feed beverage and the bubbles in the pool.

[0032] The process may include adding a bubble coalescence inhibitor to the feed beverage and / or the pool. For example, the bubble coalescence inhibitor may include any one or a combination of sucrose, amino acids, emulsifiers, surfactants, mineral salts such as sodium chloride. By way of example, the inhibitor may be selected from a group including Gylercol, L- Tyrosine or silicon dioxide.

[0033] The process may also include dampening the bubbles and / or a foam of the bubbles on an upper surface of the pool, causing the gas of the bubbles to pass into the headspace. For example, this may include touching the bubbles with a barrier. That is to say, the dampening includes physical defoaming any foam form on the surface of the pool.

[0034] The bubbles that pass into the headspace form a gas product including the gas of the bubbles and vapourised alcohol in the bubbles, and the process may include a separating step of separating alcohol from the gas product and produce a liquid alcohol and a lean gas that is lean in alcohol vapour. In one example, separating the alcohol may include cooling the gas product to condense alcohol vapour therefrom. That is to say, the separation may be carried out by differences in dew point of the vapour fractions of the product gas.

[0035] The process may include returning at least a portion of the lean gas for use of the lean gas as part of the gas delivered to the pool.

[0036] The process may include discharging at least a portion of the lean gas from the process.5P0533WO

[0037] The process may include controlling the alcohol content of the lean gas by one or more of the following: i) adjusting the temperature to which the product gas is cooled; ii) adjusting the pressure at which the separating step is operated; or iii) adjusting a recycle rate of the lean gas being returned to the separating step to pass through the separating step.

[0038] The process may also include collecting the gas phase that is enriched with alcohol from the headspace, and condensing alcohol from the gas phase to produce a high purity alcohol liquid.

[0039] The process may also include supplying the feed beverage to end of the pool and discharging the low alcohol beverage from an opposite end of the pool, and the gas stream is delivered into the pool along at least part of the length of the pool.

[0040] A gas delivery device may be arranged to deliver the bubbles into the pool. The gas delivery device may be located at a floor of the pool, and suitably along at least part of the length of the pool.

[0041] In one example, the process may be carried out in batch operation in which a volume of the feed beverage is loaded into the pool and the gas bubbles through the feed beverage for a period prior to the low alcohol beverage being discharged from the pool.

[0042] In another example, the process may be carried as a continuous operation in which the feed beverage is continuously supplied to the pool, or supplied to pool periodically in aliquots.

[0043] The present invention also relates to the reduced alcohol beverage made according to the process described herein.

[0044] The present invention also relate to the liquid alcohol product made according to the process described herein.

[0045] The present invention also relates to a plant for extracting alcohol from a feed beverage, the plant includes: a pool of the feed beverage; and a gas delivery device for delivering a gas into the pool to form bubbles in the feed beverage that rise into a headspace over the beverage, the bubbles forming a liquid / gas interface such that alcohol in the feed beverage is transferred into the bubbles and carried into the headspace, thereby extracting alcohol from the beverage and producing reduced alcohol beverage.

[0046] The plant may include a first heater for preheating feed beverage supplied to pool.

[0047] The plant may include a second heater for preheating the gas delivered to the pool.6P0533WO

[0048] The plant may include a first heater controller for controlling operation of the first heater.

[0049] The plant may include a second heater controller for controlling operation of the second heater.

[0050] The plant may include a pressure controller for controlling pressure in the headspace. For example, the pressure controller may control the pressure in the headspace to a pressure below atmospheric pressure. In another example, the pressure controller may control the pressure in the headspace to atmospheric pressure. In another example, the pressure controller may control the pressure in the headspace to a pressure above atmospheric pressure. For example, the pressure controller may operate the compressor drawing from the headspace, and / or control valves.

[0051] The pool may have any suitable depth. For example, the depth may range from 5 to 25cm, or preferably from 5 to 20cm, or preferably from 5 to 15 cm, or preferably from 8 to 13 cm, or preferably approximately 10 cm.

[0052] The plant may include a depth controller to control the depth of the pool. In one example, the depth controller may control the depth of the pool as a function of a flow rate of the gas delivered to the pool. In another example, the depth controller may control and / or varying the depth of the pool as function of the size of the bubbles of gas in the pool.

[0053] The gas delivery device may include a porous substrate located in the pool through which the gas passes and exits as the bubbles. The gas delivery device may have an

[0054] Suitably the porous substrate is located on or near a floor of the pool, so that the bubbles ascend the depth of the pool. The porous substrate may include a gas permeable material including a frit located in the pool. The porous substrate may extend the length of the pool.

[0055] The porous substrate may produce bubbles having a diameter ranging from 0.1mm to 7.0 mm. In another example, a majority of the bubbles may have a diameter ranging from 1.0 mm to 3.0 mm.

[0056] The porous substrate may have pore openings ranging from 10 microns to 500 microns, and preferably from 20 microns to 250 microns, and preferably from 40 microns to 100 microns.

[0057] The plant may include a dampener barrier arranged to contact bubbles at the top of the pool to cause the gas of the bubbles to pass into the headspace.

[0058] The bubbles passing into the headspace form a gas product including the gas of the bubbles and vapourised alcohol, and the plant may include separator for separating alcohol from the gas7P0533WOproduct and produce a liquid alcohol and a lean gas that is lean in alcohol vapour. In one example, the separator may include a condenser cooler for condensing alcohol vapour from the gas product.

[0059] The plant may include a ratio controller to control a ratio of the volume of the bubbles in the pool to the total volume of the pool, include the bubbles and the feed beverage in the pool. In one example, the volume of the bubbles ranges from 10% to 60% of the total volume of the pool, including the feed beverage and the bubbles in the pool.

[0060] The plant may include a content controller to control the alcohol content of the lean gas by one or more of the following: i) adjusting the temperature to which the product gas is cooled; ii) adjusting the pressure at which the separating step is operated; or iii) adjusting a recycle rate of the lean gas being returned to the separating step to pass through the separating step.

[0061] The plant may also include a chamber in which the pool and headspace are located, the chamber having: an inlet for the feed beverage at one end of the chamber, an outlet at another end of the chamber to allow a reduced alcohol beverage to be discharged from the pool; and the gas delivery device arranged to deliver the gas as bubbles into the pool.

[0062] The gas delivery device may have a surface facing the pool from which the bubbles are delivered to the pool.

[0063] The plant may also include any one or a combination of the features of the process described herein. Similarly, the process may also include any one or a combination of the features of the plant described herein.

[0064] The term "alcohol" as used throughout this specification refers to ethanol, and the two have been used interchangeably in this specification.

[0065] The term "trace amounts" means effectively zero alcohol vol%BRIEF DESCRIPTION OF THE DRAWINGS

[0066] A preferred embodiment will now be described with reference to the accompanying Figures, which may be summarized as follows.

[0067] Figure 1 is a flow diagram of a plant and process for extracting alcohol from a feed beverage to produce a reduced alcohol beverage.8P0533WO

[0068] Figure 2 is a flow diagram of the plant and process as shown in Figure 1, and in addition also includes separating alcohol from a product gas to produce a liquid alcohol and a lean gas that can be recycled.DETAILED DESCRIPTION

[0069] Figures 1 and 2 are schematic illustrations of a process 10 and plant 11 for extracting alcohol from a feed beverage 29 to the produce a reduced alcohol beverage 30. The term reduced alcohol beverage 30 as used herein embraces the beverage having a reduced alcohol content compared to the beverage before being treated according to the process. For example, the beverage having a zero alcohol content such as a trace alcohol content. The feed beverage 29 may be obtained from any brewing, fermentation, or distillation process including beer or wine, including fortified and unfortified wines, or distilled products including spirits and so forth. The feed beverage 29 may also be any intermediate solution made in these processes.

[0070] The process 10 (and plant 11) includes forming a pool 13 of the feed beverage 29 in a chamber 12. Specifically, the feed beverage 29 is conveyed continuously, semi-continuously, or batchwise via a beverage inlet 17, at one end of the chamber 12, into the pool 13. A headspace 14 is provided above the pool 13.

[0071] The process 10 (and plant 11) includes delivering a gas 31 into the pool 13 to form bubbles 26 of the gas in the pool 13. The bubbles 26 ascend in the pool 13 and pass into the headspace 14. The bubbles 26 form a liquid and gas interface with the feed beverage 29 such that alcohol in the feed beverage 29 is transferred into the gas 31 of the bubbles 26 and carried into the headspace 14, thereby extracting alcohol from the feed beverage 29 and producing the reduced alcohol beverage 30. The bubbles 26 passing into the headspace 14 also produce a gas product 20.

[0072] The reduced alcohol beverage 30 is discharged via a beverage outlet 18 from the chamber 12, and the gas product 20 containing alcohol in gaseous form is discharged from the headspace 14 of the chamber 12 via gas product outlet 19.

[0073] The process 10 (and plant 11) may include supplying the gas 31 to the process 10 by supplying any suitable gas source 21, such as bottled gas, an external gas pipe, or obtained from ambient air. The gas 31 may be any suitable gas supplied by the gas source 21. For instance, the gas 31 may include any one or a combination of carbon dioxide gas (CO2), nitrogen gas (N2), air, oxygen gas (O2), or an inert gas such as Helium (He) and argon (Ar). In the situation where air is used as the gas 31, the process 10 and plant 11 may also include a preliminary scrubbing step or preliminary stage, not illustrated in Figures 1 and 2 in which air is scrubbed to remove oxygen gas, and optionally9P0533WOcarbon dioxide gas so that the gas 31 supplied to the process is high purity nitrogen gas. In one example, the scrubbing step may be carried out using gas permeable membrane that allow select gas species to transfer through the membrane and prevent other gas species from transferring. In another example the scrubbing step may be carried out using a zeolite material that can be used a pressure swing to selectively adsorbs and desorb.

[0074] The process 10 (and plant 11) includes delivering the gas 31 from the gas source 21 into the pool 13 via a gas delivery device 25 to form bubbles 26 of the gas in the pool 13. The gas delivery device 25 comprises a porous material or gas permeable material that allows the gas 31 to pass through the gas delivery device 25 and hold the beverage up above the porous or the gas permeable material. The bubbles 26 may have a diameter in the range of 0.1mm to 7.0mm. The size of the bubbles 26 will affect the area of the liquid / gas interface per volume of the pool and the rate at which the alcohol is extracted from the feed beverage 29. The gas delivery device 25 may extend along the pool 13 and release bubbles 26 lengthwise along the pool 13. The bubbles 26 in the feed beverage 29 form liquid-gas interfaces that enables alcohol in the feed beverage 29 to be volatilized into the bubbles 26, and then exit the feed beverage 29 by the bubbles 26 ascend in the feed beverage 29 and disburse amongst the gas phase in the headspace 14. In addition, a liquid-gas interface will also be present between the pool 13 itself and the gas in the headspace 14.

[0075] The alcohol content of the feed beverage 29 will be the result of the brewing or distilling process from which the feed beverage 29 is produced. Generally speaking however, the process 10 and plant 11 are capable of extracting alcohol from any feed beverage 29 to produce a reduced alcohol beverage 30. For example, spirits containing 65+ vol% (%ABV) can be reduced to 0.5 to 5 vol% (%ABV), similarly wines of 20+ vol% (%ABV) can be reduced to 0.5 vol% (%ABV), and similarly beer of 6.5+ vol% (%ABV) can be reduced to 0.5 vol% (%ABV).

[0076] As shown in Figures 1 and 2, the process 10 (and plant 11) may including returning a substream of the reduced alcohol beverage 30 via a return loop 24 and mixing the substream with fresh feed beverage 29 as a means for controlling 46 the alcohol content of the reduced alcohol beverage 30. Controlling 46 the alcohol content of the beverage 30 may include operating the pump 47 and control valve 48 to control flow in return loop 24. A sensor 49 may also provide an output signal to the control. The sensor 49 may be located inline with return loop 24 or remotely from the return loop 24. Similarly, the process 10 (and plant 11) may include controlling 46 the flow rate of the gas 31 delivered to the pool 13, which can have an impact on the rate at which alcohol is extracted from the feed beverage 29. Furthermore, the process 10 (and plant 11) may include controlling 46 the10P0533WOflow rate of the feed beverage 29 delivered to, and discharged from, the pool 13 as this can also have an impact on the rate at which alcohol is extracted from the feed beverage 29.

[0077] One of advantages of the process 10 (and plantll) is that they can be operated at ambient conditions which is believed to minimize any impact on the inherent desired properties of the beverage, including flavour and aroma. By way of example, under ambient conditions, the feed beverage 29 and the gas 31 may have temperatures in the range of 5 to 25°C. It is also possible that the feed beverage and / or gas may be cooled to temperature below 18°C using refrigeration. For example, some beer brewing processes brew at a temperature ranging from 5 to 13°C, such as bottom fermented lagers. These lagers could be used as the feed beverage 29 at the temperature range of 5 to 13°C. Similarly, in the case where the feed beverage is heated or the cooled, the feed beverage could have a temperature above or below the range of the 5 to 13°C.

[0078] The process 10 (and plant 11) may include heating either one or a combination of the feed beverage 29 or the gas 31 to increase the rate at which alcohol is volatilized from the feed beverage 29 into the bubbles 26. Increasing the temperature of the feed beverage 29 may also increase the rate at which the alcohol is vapourized from the surface of the pool 13 facing the headspace 14. As can be seen, first and second heaters 15 and 16 are arranged in the supply lines of the feed beverage 29 and the gas 31, respectively, for heating the feed beverage 29 and the gas 31. The process 10 may include controlling 46 the temperature of gas delivered to the pool 13 via the first heater 15. The process may include controlling 46 the temperature of the feed beverage via the second heater 16. In addition, the latent heat of vaporisation of alcohol from the feed beverage 29 will also have a cooling effect on the feed beverage 29. To maintain the temperature of the feed beverage 29 above a desired temperature in the pool 13, the feed beverage 29 may be preheated by heater 15.Although not shown in the Figures, the process may also include heating the feed beverage 29 in the pool 13. For example, by means of the heated jacket on the pool 13 or heating coils located in the pool 13.

[0079] Although the chamber 12 can be operated at close to ambient conditions, if required the process 11 can include controlling 46 the pressure of the headspace 14 by operating a first compressor 22 drawing from the headspace 14 to a pressure at or below atmospheric pressure which will reduce the boiling point of alcohol and potentially increase the rate of extraction of alcohol per volume of bubbles 26. In addition, if required the process can include controlling 46 the pressure of the gas 31 delivered to the pool 13 to pressure above atmospheric conditions by coordinating operation of a second compressor 23 that delivers the gas 31 and a flow restrictor, such as a control valve 28, that regulates the pressure of the gas product 20.11P0533WO

[0080] In addition to temperature, pressure, and average residence time of the feed beverage 29 in the pool 13, we have found that the depth of the pool 13 may impact the extraction of alcohol from the feed beverage 29. In our experience a depth in the range of 5 to 25cm and suitably approximately 10cm is preferred for bubbles 26 ranging in size from 0.1mm to 7.0mm. However, it will be appreciated that other depths may also be preferred, particular for bubbles smaller than 0.1mm in diameter or greater than 7.0mm.

[0081] The gas 31 can be delivered into the pool 13 using a gas delivery device 25 having any suitable gas permeable material on which the feed beverage 29 can be held up. Examples of suitable devices include a gas sparge, a gas frit, a gas sinter, or piping having appropriate openings for discharging the gas and forming the bubbles 26 in the pool 13. The bubbles 26 may have any suitable diameter, and typically have a diameter ranging from 0.1mm to 7.0 mm, and ideally in the range of 3.0mm to 7.0mm. However, the optimal size will vary depending on depth of the pool 13, temperature, feed beverage flow rate and so forth. In addition, it will also be appreciated that the size of the bubbles 26 can change from when they are first delivered into the pool 13 to the time that exit the pool 13, for example, microbubbles can coalesce to form larger bubbles in the pool 13. The process may include controlling 46 the depth of the pool 13 as a function of the flow rate of the gas 31 delivered to the pool 13. In any event, the process 10 may include controlling the depth of the pool 13 to a range from 5 to 25cm, and suitably approximately 10cm.

[0082] The diameter of the bubbles 26 may also have an impact on rate of transfer of alcohol into the bubbles 26. For instance, as the bubbles 26 reduce in the size, a ratio of the surface area to the volume of the bubbles 26 will increase, facilitating transfer of the alcohol into the vapour phase of the bubble per volume of the bubbles 26. However, as the size of the bubbles 26 decreases the speed at which they will ascend in the feed beverage 29 reduces and their tendency to coalesce with other bubbles 26 increases. Conversely, bubbles 26 that are too large may ascend more quickly.

[0083] In any event, the process 10 (and plant 11) may include controlling 46 a ratio of the volume of the bubbles 26 in the pool 13 to the volume of the feed beverage 19 in the pool 13. In one example, the volume of the bubbles 26 ranges from 10% to 60% of the total volume of the pool, including the feed beverage 29 and the bubbles 26 in the pool 13.

[0084] In addition, the process 10 may include adding a bubble coalescence inhibitor 32 to the feed beverage 29 being supplied to the chamber 12. It will also be appreciated that the bubble coalescence inhibitor 32 may be added to the pool 13 and / or to the feed beverage 29. By way of example, the bubble coalescence inhibitor 32 may include any one or a combination of sucrose such12P0533WOas Glycerol, amino acids such as L-Tyrosine, emulsifiers, surfactants, mineral salts such as sodium chloride, and antifoaming agents.

[0085] As can be seen, the process 10 and plant 11 may also include dampening bubbles 26 or an accumulation of the bubbles 26, such as a foam, on the surface of the pool 13, thereby causing the gas 31 at the surface of the pool 13 to pass into the headspace 14. It is possible that if the bubbles were left to accumulate the passage of the gas containing alcohol into the headspace 14 may be slowed down, reducing the efficiency of the process 10. Dampening step may be carried out in addition to, or instead of, adding the bubble coalescence inhibitor 32. Dampening bubbles 26 or a foam comprising the bubbles 26 may be carried out using a dampening device 33 above the pool 13 which acts as a physical barrier to assist in defoaming the surface of the pool 13.

[0086] Although not shown in Figure 1, Figure 2 also illustrates a separating step 34 for separating at least part of the alcohol content from the gas product 20, and suitably 75 to 98% of the alcohol content form the gas product 20, to product a liquid alcohol product 35 in the form of a high purity alcohol product, and a lean gas that is lean in alcohol vapour exiting the separating step 34. A portion of the lean gas can be used as a recycle gas 36 that can be returned back to the gas source 21. A balance of the lean gas not recycled can be discharged from the process 10 as discharge gas 37. It will also be appreciated that the recycle gas 36 can be returned directly or indirectly to the pool 13, for example, to the delivery device 25. The separating step 34 may include cooling the product gas 20 with a condenser 39 located in the separator to condense alcohol from the product gas 20, and in which condensed alcohol can run to the bottom. If required, a portion of recycle gas 36 can also be recycled back via loop 40 so that it can be passed through the separating step 34 again. Indeed, the process 10 can include controlling 46 the alcohol content of the recycle gas by adjusting the flow of the recycle gas 36 returned to the separating step 34.

[0087] Moreover, the process may include controlling 46 the alcohol content of the lean gas / recycle gas 36 by one or more of the following, i) Adjusting the temperature to which the product gas is cooled during colling 38, 39. ii) Adjusting the pressure at which the separating step 34 is operated, for example, controlling the compressor 22. iii) Adjusting a ate at which the recycle gas 36 is returned to the separating step 34 via loop 40. The alcohol content of the lean gas / recycle gas 36 may be monitored via sensor 50 which may be located in line or out of line of the recycle gas 36. Likewise, the sensor 50 may be located in, or sample the lean gas and / or the discharge gas 37.

[0088] The separating step 34 may also include further optional cooling, not illustrated in Figure 2, and optionally passing the recycle gas 36 through a further separating step 41, such as a cyclone13P0533WOseparator. A further liquid alcohol product 42 can be discharged from the cyclone separator and the recycle gas stream delivered to the gas source and / or delivered to the pool 13.

[0089] With reference to Figure 1, the plant 11 includes a line for delivering a feed beverage 29 into a chamber 12 by an inlet 17. The chamber 12 also includes a gas delivered device 25 and a pool 13 of the feed beverage 29. A gas source 21 is connected to gas delivered device 25 and the gas delivery device 25 is arranged so that the gas delivered by the gas source 21 forms bubbles 26 of the gas 31 in the pool 13. As mentioned, the gas deliver deice 25 may be formed using any suitable sparge, sinter, or porous substrate. The bubbles 26 formed in the pool 13 ascend in the pool 13 and alcohol in the feed beverage 29 in the pool 13 is transferred to the gas of the bubbles 29 and into a headspace 14 of the chamber 12 above the pool 13. Gas product 20 in the headspace 14 exits the plant 11. The headspace 11 can be operated at any desired pressure, including sub-atmospheric, atmospheric, or above atmospheric pressure by operating control valve 28 and compressor 22.

[0090] The gas source 21 may be any suitable source including bottled gas, or the ambient gas. Although not shown in the Figure 1, the gas source 21 may also include a preliminary scrubber for filtering the gas 31, and / or for scrubbing the gas. For example, when ambient air is used as the gas source 21, a preliminary scrubber, such as a zeolite absorbent or gas permeable membrane, may be used to absorb oxygen and / or carbon dioxide from the air so that nitrogen gas can be used as the gas 31 delivered to the delivering device 25. It will be appreciated that water vapour will also be absorbed by the zeolite absorbent. The temperature and pressure of the gas 31 delivered by the delivering device 25 can be controlled by the compressor 23, second heater 16 and valves, although the latter is not show in Figures 1 and 2.

[0091] The plant 11 includes a valve for controlling the flow of the feed beverage 29 into the pool 13, and a first heater 15 for preheating the feed beverage 29 prior to being delivered into the pool 13. The pant 11 may also include an additive inlet 43 for adding a bubble coalescence inhibitor 32. The inlet 43 may be arranged in the line that conveys the feed beverage 29 as shown, or although not shown, the inlet 43 may be arranged to supply the bubble coalescence inhibitor 32 directly into the pool 13.

[0092] The controller 46 represents a single controller or multiple controllers, and irrespective of the form, the controller 46 presents any one or a combination of the following, i) A first heater controller for controlling operation of the first heater, ii) A second heater controller for controlling operation of the second heater, iii) A pressure controller for controlling pressure in the headspace. For example, the pressure controller may control the pressure in the headspace to a pressure below atmospheric pressure. In another example, the pressure controller may control the pressure in the14P0533WOheadspace to atmospheric pressure. In another example, the pressure controller may control the pressure in the headspace to a pressure above atmospheric pressure. For example, the pressure controller may operate the compressor drawing from the headspace, and / or control valves. Iv) A depth controller to control the depth of the pool. In one example, the depth controller may control the depth of the pool as a function of a flow rate of the gas delivered to the pool. In another example, the depth controller may control and / or varying the depth of the pool as function of the size of the bubbles of gas in the pool.

[0093] The plant 11 shown in Figure 2 is the same as the plant 11 shown in Figure 1, the description of the plant 11 herein therefore also applies to the plant 11 shown in Figure 2. In addition, plant 11 in Figure 2 includes the additional feature of a separator 44 for separating the alcohol component of the product gas 20. Specifically, the separator 44 includes an inlet for the product gas 20 and a cooling means 39 located inside the separator 44 for condensing at least part, and suitably 75 to 98% of the alcohol content form the gas product 20. The separator 44 has a bottom outlet for discharging a liquid alcohol product 35 in the form of a high purity alcohol product, and an upper outlet for discharging a (lean) recycle gas 36 that is lean in alcohol. A recycle loop 40 allows a portion of the lean gas 36 to be returned to the inlet of the separator 44, thereby allowing the alcohol content of the recycle gas 36 to be controlled by being recycled back through the separator 44. In addition, a T- junction allows a portion of the recycle gas 36 to be returned back to the gas source 21 and a balance of the recycle (lean) gas 36 not recycle can be discharged from the plant as discharge gas 37. It will also be appreciated that the recycle gas 36 can be returned directly or indirectly to the pool 13, for example, to the delivery device 25.

[0094] The separating step 34 may also include a further optional cooler, not illustrated in Figure 2, and a further separator 45 such as a cyclone separator. A further (high purity) alcohol product 42 can be discharged from the cyclone separator and the recycle gas 36 delivered to the gas source and / or delivered to the pool 13.

[0095] The controller 46 may include a content controller to control the alcohol content of the lean gas by one or more of the following: i) adjusting the temperature to which the product gas is cooled in the separator; ii) adjusting the pressure at which the separator is operated; or iii) adjusting a flow rate of the lean gas being returned back to the separator.

[0096] The plant 11 described herein may also include any one of the features of the process 10 described. Likewise, the process 10 described herein may also include any one of the features of the plant 11 described.15P0533WO

[0097] Signals to the controlling step / controller, both identified by reference numeral 46, have been generically represented in Figures 1 and 2 by dashed lines connecting to process steps or plant items. The controller step / controller 46 can carry out any suitable calculations that may be programmed or hardwired.EXAMPLE

[0098] The process was tested using a sintered bubble column operating under ambient atmospheric pressure. The column contained 100 ml of the beverage sample at a depth of approximately 10mm. The column was provided by a 1000 ml Buchner funnel with a sinter base through which an evaporating gas was conveyed to form bubbles in the beverage. The frit / sinter used had pore index of great than 40 microns and less than or equal to 100 microns. The sinter provided a bubble size in the range of 0.1mm to 7.0 mm, a majority of the bubbles may have a diameter ranging from 1.0 mm to 3.0 mm with a level coalescence occurring. Two trials were conducted using this test apparatus and further details of these trials is as follows. The alcohol content of the beverages, both before and after the trials, was measured using an NIR Alex 500, alcohol and extract meter, commercially available from Anton Parr GmbH.First Trial

[0099] In the case of first trial, the gas types were supplied at ambient room temperature, i.e., approximately 20°C and the beverage was supplied at a sub-boiling temperate, approximately 23°C. In addition, the first trial involved adding additives to the beverage, namely an amino acid solution, particularly, L-Tyrosine to reduce bubble coalescence was added to Samples B to D. L-Tyrosine allowed very small bubbles to form at the sinter, and large bubbles formed by coalescence at the top of the solution. Although L-Tyrosine may act as a coalescence inhibition, the first trail also included adding Glycerol to Samples B to D, to act as a surfactant to aid in the removal of ethanol from beverages. Silicon dioxide was added to Sample A as an anti-foaming agent. Each of these additives were selected and tested because that are considered to not have an impact on the components of red wine, or other beverages. However, it will be appreciated that the other additives can be used to reduce bubble coalescence, for instance, other amino acids can be used instead of L-Tyrosine. Likewise other anti-foaming agents including silicon-based agents, such as polydimethylsiloxane could be used instead or in addition to silicon dioxide, or polyether-based agents. However to our surprise, chromatographic analysis of the tested samples from the first trial indicated that L-Tyrosine and Glycerol were not present, which suggests that the evaporation mechanism of ethanol may only be effected by the additives by a small extent, and that the principle evaporation mechanism of16P0533WOethanol can be related to selective ethanol adsorption at the air-water interface (i.e., bubble surface), depending on the type of inlet gas used.TABLE 1

[0100] The alcohol content analysis, conducted using the NIR Alex 500 meter, showed that alcohol content of Red Wine reduced by an amount in the range of 55.9% to 81.5% of the original alcohol content. A 55.9 vol% reduction being provided by Sample D in which the alcohol reduced by 7.55 vol% compared to the original content of 13.5 vol%. A reduction of 81.5 vol% being most in TABLE 1 being provided by Sample B in which the alcohol content reduced by 11.0 vol% compared to the original content of 13.5 vol%. However, it will be appreciated that the original alcohol content can be reduced by up to 95% and event to 100%, that is the alcohol content can be taken down to zero or only trace amounts, by increasing the period over which the gas is bubbled through the beverage.

[0101] The type of gas can also have an influence used. For instance, when Helium was used, the alcohol content was 2.9 vol% at one-quarter the gas flow rate (5 L / min), compared to 2.5 vol % alcohol remaining when Nitrogen was used (21 L / min) (see TABLE 1). These results indicate that the use of Helium significantly contributes to the amount of alcohol evaporated in the bubble column.

[0102] A subjective taste test was also conducted and no appreciable taste difference between the untested beverage and the beverage tested was obtained. This was confirmed by chromatographic testing in which aroma-related compounds known to possess a significant influence on the taste of17P0533WORed Wine, such as iso-butanol, ammonium acetate, 3-methyl-l-butanol, ethyl lactate, 2- phenylethanol, were present in the tested Samples. In addition to these compounds, taste-active components of Red Wine including isoamyl acetate, ethyl hexanoate, 2-phenylethanol, ethyl octanoate were also found to be present in the tested samples. Chromatographic testing was carried out using mass spectrometer knows as a GCMS-QP2020 NX which is commercially available from Shimadzu of Australia and New Zealand.Second Trial

[0103] In view of the first trial, a second trial was conducted without the addition of any additives t the beverage. The second trial was conducted using substantially the same apparatus, the beverage and evaporating gas were both supplied at ambient room temperature of approximately 20°C and the gas flow rate was maintained at equal to or less 23 L / min. Again an alcohol content analysis was conducted using the NIR Alex 500 meter, which showed that the alcohol content of Sample E (Red Wine) reduced by an amount of approximately 39.4% (i.e., a reduction of 5.16 vol% by the initial content of 13.13 to 7.96 vol%) in 45 mins when nitrogen gas was used. The alcohol content of Sample F (Red Wine) reduced by an amount of approximately 79.7% (ie., a reduction of 10.47 vol% divided by the original content of 13.13 vol %) in 120 mins. The same calculations for Samples G, H and I provide reductions of 41.9%, 42.8% and 59.8% respectively, see TABLE 2.

[0104] In any event, it will be appreciated that the original alcohol content can be reduced by up to 95% and event to 100%, that is the alcohol content can be taken down to zero or only trace amounts, by increasing the period over which the gas is bubbled through the beverageTABLE 218P0533WO

[0105] Those skilled in the art of the present invention will appreciate that many variations and modifications may be made to the preferred embodiment and the example described herein without departing from the spirit and scope of the present invention.Reference Numeral Table19P0533WO

Claims

CLAIMS1. A process for extracting alcohol from a feed beverage, in which the process includes: forming a pool of the feed beverage; and delivering a gas into the pool to form bubbles that ascend in the feed beverage and pass into a headspace over the beverage, the bubbles forming a liquid / gas interface with the feed beverage such that alcohol in the feed beverage is transferred into the bubbles and carried into the headspace, thereby extracting alcohol from the feed beverage and producing a reduced alcohol beverage.

2. The process according to claim 1, wherein the gas is any one or a combination of carbon dioxide, nitrogen, air, oxygen, helium, or argon.

3. The process according any one of the preceding claims, wherein alcohol is extracted from the feed beverage so that the reduced alcohol beverage is less than an initial alcohol content of the feed beverage.

4. The process according to claim 3, wherein the initial alcohol content of the feed beverage is 30+ vol % for spirits, 12+ vol% for wine, and 3+ vol% for beer, and the reduced alcohol beverage is less than 3 vol%, or in the range from 3 vol% to only trace amounts (alcohol by volume ABV).

5. The process according to any one of claims 1 to 3, wherein the initial alcohol content of the feed beverage has an alcohol content ranging from 22 vol% to 9 vol%, and the alcohol content of the reduced alcohol beverage is less than 3.0 vol %, in the range from 3 vol% to only tracer amounts.

6. The process according to any one of the preceding claims, wherein the alcohol content of the reduce alcohol beverage is in the range of the 40 to 100% less than the alcohol content of the feed beverage.

7. The process according any one of the preceding claims, wherein the gas and / or the feed beverage have an ambient temperature, such as from 3 to 25 °C.

8. The process according any one of claims 1 to 6, wherein the gas delivered into the pool has a temperature ranging from 25 to 80°C.

9. The process according any one of claims 1 to 6 or claim 8, wherein the feed beverage supplied to the pool has a temperature ranging from 25 to 80°C.

10. The process according any one of the preceding claims, wherein the process includes controlling the pressure in the headspace at a pressure below atmospheric pressure.20P0533WO11. The process according any one of claim 1 to 9, wherein the process includes controlling the pressure in the headspace to atmospheric pressure.

12. The process according any one of the preceding claims, wherein the process includes controlling the pressure in the headspace at a pressure above atmospheric pressure13. The process according any one of the preceding claims, wherein the process includes controlling the depth of the pool to a range from 5 to 25cm, and suitably from 8 to 13 cm.

14. The process according any one of the preceding claims, wherein the bubbles have a diameter ranging from 0.1mm to 7.0 mm, and suitably from 1.0 mm to 3.0 mm.

15. The process according any one of the preceding claims, wherein the process includes forming the bubbles by passing the gas through a porous substrate located in the pool.

16. The process according any one of the preceding claims, wherein the process includes controlling a ratio of the volume of the bubbles in the pool to the total volume of the pool, include the bubble and the feed beverage.

17. The process according to claim 12, wherein the ratio of the volume of the bubbles ranges from 10% to 60% of the total volume of the pool, including the feed beverage and the bubbles in the pool.

18. The process according any one of the preceding claims, wherein the process includes adding a bubble coalescence inhibitor to the feed beverage and / or the pool.

19. The process according any one of the preceding claims, wherein the process includes dampening the bubbles and / or a foam of the bubbles on an upper surface of the pool, causing the gas of the bubbles to pass into the headspace.

20. The process according to any one of the preceding claims, wherein bubbles that pass into the headspace form a gas product including the gas of the bubbles and vapourised alcohol in the bubbles, and the process may include a separating step of separating alcohol from the gas product and produce a liquid alcohol and a lean gas that is lean in alcohol vapour.

21. The process according to claim 20, wherein separating the alcohol may include cooling the gas product to condense alcohol vapour therefrom.

22. The process according to claim 20 or 21, wherein the process includes returning at least a portion of the lean gas for use of the lean gas as part of the gas delivered to the pool.21P0533WO23. The process according to any one of claims 20 to 22, wherein the process includes controlling the alcohol content of the lean gas by one or more of the following: i) adjusting the temperature to which the product gas is cooled; ii) adjusting the pressure at which the separating step is operated; or iii) adjusting a recycle rate of the lean gas being returned to the separating step to pass through the separating step.

24. The reduced alcohol beverage made according to the process of any one of claims 1 to 23.

25. The liquid alcohol product made according to the process of any one of claims 20 to 23.

26. A plant for extracting alcohol from a feed beverage, the plant includes: a pool of the feed beverage; and a gas delivery device for delivering a gas into the pool to form bubbles in the feed beverage that rise into a headspace over the beverage, the bubbles forming a liquid / gas interface such that alcohol in the feed beverage is transferred into the bubbles and carried into the headspace, thereby extracting alcohol from the beverage and producing reduced alcohol beverage.

27. The plant according to claim 26, wherein the plant includes a first heater for preheating feed beverage supplied to pool.

28. The plant according to claim 27, wherein the plant includes a first heater controller for controlling operation of the first heater.

29. The plant according to any one of claims 26 to 28, wherein the plant includes a second heater for preheating the gas delivered to the pool.

30. The plant according to claim 29, wherein the plant includes a second heater controller for controlling operation of the second heater.

31. The plant according to any one of claims 26 to 30, wherein the plant includes a pressure controller for controlling pressure in the headspace.

32. The plant according to any one of claims 26 to 30, wherein the pool has a depth ranging from 5 to 25cm, or preferably from 5 to 20cm, or preferably from 5 to 15 cm, or preferably from 8 to 13 cm, or preferably approximately 10 cm.

33. The plant according to any one of claims 26 to 32, wherein the plant includes a depth controller to control the depth of the pool.22P0533WO34. The plant according to any one of claims 26 to 33, wherein the gas delivery device includes a porous substrate located in the pool through which the gas passes and exits as the bubbles.

35. The plant according to any one of claims 26 to 30, wherein the porous substrate has pore openings ranging from 10 microns to 500 microns, and preferably from 20 microns to 250 microns, and preferably from 40 microns to 100 microns.

36. The plant according to any one of claims 26 to 35, wherein the plant includes a dampener barrier arranged to contact bubbles at the top of the pool to cause the gas of the bubbles to pass into the headspace.

37. The plant according to any one of claims 26 to 36, wherein the bubbles passing into the headspace form a gas product including the gas of the bubbles and vapourised alcohol, and the plant includes separator for separating alcohol from the gas product and produce a liquid alcohol and a lean gas that is lean in alcohol vapour.

38. The plant according to any one of claims 26 to 37, wherein the plant includes a ratio controller to control a ratio of the volume of the bubbles in the pool to the total volume of the pool, include the bubbles and the feed beverage in the pool.

39. The plant according to any one of claims 26 to 38, wherein the plant includes a content controller to control the alcohol content of the lean gas by one or more of the following: i) adjusting the temperature to which the product gas is cooled; ii) adjusting the pressure at which the separating step is operated; or iii) adjusting a recycle rate of the lean gas being returned to the separating step to pass through the separating step.23P0533WO

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