GB2492340A

GB2492340A - Extracting a beverage such as coffee using heated water

Info

Publication number: GB2492340A
Application number: GB201110918A
Authority: GB
Inventors: Francisco Javier Silanes Kenny; Ian Denis Fisk
Original assignee: Kraft Foods R&D Inc USA
Current assignee: Kraft Foods R&D Inc USA
Priority date: 2011-06-27
Filing date: 2011-06-27
Publication date: 2013-01-02
Also published as: GB201110918D0

Abstract

An apparatus for beverage extraction comprises an extraction cell, defining a chamber 11 for containing an extractable material 12 such as coffee grounds or chocolate slurry, an inlet 13 and outlet 14 for water, and a heat source 15 configured to heat the water while the water is situated inside the extraction cell. The heat source may comprise an oil jacket or alternatively microwave heating. A plurality of the apparatuses may be provided in a system. A method of extracting a beverage is also described.

Description

BEVERAGE EXTRACT ION

Technical Field

This disclosure is directed to art apparatus and process for beverage extraction, and in particular to an apparatus and process f or beverage extraction using microwave energy.

Background

Soluble coffees (also known as instant coffees) are attractive to the consumer for their ability to provide a quick method of making a coffee beverage without having to go through a brewing process. Soluble coffees are dried extracts of coffee beans in powder or granular form that, when mixed with hot water, dissolve to form a coffee beverage. Soluble coffee may be derived from any variety or type of coffee bean or any combination of any varieties and/or types.

One method which is typically used to obtain soluble coffee from coffee beans is as follows.

Before roasting the coffee, the "green" coffee beans may be processed, for example to remove caffeine. Suitable decaffeination processes include treating the beans with a heated coffee extract, direct or indirect decaffeination with a solvent such as water, dichioromethane, ethyl acetate, or triglyceride, and extraction using supercritical carbon dioxide. Other treatment steps before roasting may also be carried out, for example treatment to modulate flavour-producing compounds in the green coffee bean.

The green coffee beans are then roasted. Roasting is well known in the art. Typically, it involves heating the green beans until they change colour, typically using ovens and fluidised beds.

After roasting, the coffee beans may be further treated, for example to increase (or decrease) thee level of hydration, or to induce a unique flavour characteristic such as espresso. The coffee beans are then ground. Typical grinding methods include burr grinding, chopping, pounding, and roller grinding.

The roasted coffee grounds are then extracted by passing hot water through the coffee grounds under pressure.

A conventional extraction process is described in US-B- 5151287, wherein coffee is extracted by passing hot water through a series of four to eight cells (or columns) filled with the ground roasted coffee. Hot water, under pressure and at a temperature of 150°C-180°C, is introduced into the cell containing the batch of ground roasted coffee which has been most intensively extracted. The liquid extract from this cell is then passed through the extraction cell containing the batch of coffee which has been next most intensively extracted, and so on, until the liquid extract passes through the cell which is filled with fresh ground roasted coffee. The final extract leaves the last cell at a temperature in the order of 100°C. After each extraction cycle, the cell containing the most intensively extracted coffee is emptied, filled with fresh coffee and, after the cells have been rearranged, another extraction cycle begins.

The coffee extract may then be concentrated, for example from about 15% to about 50% coffee by mass or more.

The concentrated extract is then dried, for example by freeze drying or spray drying. Methods of freeze drying and spray drying are well known in the art.

An ongoing challenge for the soluble coffee industry is the development of high extraction yield processes with low energy consumption. A disadvantage of the previously described conventional process for coffee extraction is that the water has to be pre-heated to a very high temperature in order to compensate for heat energy which is dissipated when transmitting the water to the first cell, and in its progress from cell to cell. Additionally, advantageously high pressures are not maintained during the extraction process.

Summary

According to the present disclosure there is provided an apparatus for beverage extraction, comprising: an extraction cell defining a chamber for containing an extractable material; an inlet for water to enter the extraction cell; an outlet for water to leave the extraction cell; and a heat source configured to heat water inside the extraction cell. 3D

The present disclosure further provides a plurality of apparatuses for beverage extraction, wherein at least one of the apparatuses for beverage extraction is as defined above.

The present disclosure further provides a method for extracting a beverage, comprising the step of: contacting beverage grounds with water within the aforemention apparatus for beverage extraction; wherein water in the apparatus for beverage extraction is heated by the heat source.

By providing a heat source which is able to heat water within the beverage extraction apparatus, additional heating of the water prior to its transmission to the cell to account for heat dissipation is not required, which results in an energy saving.

Additionally, heating water inside the extraction cell results in a pressure increase in the cell. Heating water inside the extraction cell results in a lesser temperature drop inside the column than for conventional extraction, where all the energy is carried by the water at the feed, and therefore lower feed temperatures may be used for the same degree of extraction. In the case of coffee extraction, extraction at a lower temperature means less thermal damage to the coffee grounds.

The use of microwave energy as the heat source provides the further advantage of more homogeneous heating of the water.

Overall, the present disclosure provides high yield benefits and reduced energy costs, with additional product quality benefits.

Exemplary embodiments of a beverage extraction process are described with reference to, and as shown in, the accompanying drawings.

Brief Description of the Drawings

Figure 1 is a schematic view of an apparatus for beverage extraction according to the present disclosure; and Figure 2 is a schematic view of a coffee extraction system comprising a plurality of interconnected apparatuses for beverage extraction, wherein at least one of the apparatuses for beverage extraction is of the type illustrated in Figure 1.

Detailed Description

Figure 1 illustrates an apparatus for beverage extraction 10 according to the present disclosure. The extraction apparatus 10 is particularly suitable for coffee extraction and comprises an extraction cell 11 defining a chamber for the ingredients 12 to be extracted, such as roasted coffee grounds. Water, or another suitable liquid, enters the extraction cell 11 at inlet 13 and leaves the chamber 11 at outlet 14. The water may be heated prior to entry to the extraction cell 11. The pressure inside the cell is determined by the vapour pressure of the water at the relevant temperature.

A heat source 15 is located in the vicinity of the extraction cell 10 such that the heat source 15 is able to provide heat energy to the water inside the cell 10 during the extraction process. The heat source may take any suitable form, for example a heated oil jacket surrounding the extraction cell 10. More preferably, the heat source comprises a source of microwave energy. The heat source 15 may be used to maintain the feed temperature of the water (i.e. the temperature upon entry to the extraction cell 11) during the extraction process. Alternatively, the heat source 15 may be used to increase the temperature of the water when it is inside the extraction cell 11. The final temperature and pressure reached inside the cell can be modified depending on the desired degree of extraction.

Figure 2 shows an extraction system comprising a plurality of extraction apparatuses 21-26 in fluid communication with each other. The fluid communication means between the apparatuses 21-26 may comprise pipes, hoses, or any other suitable connection means. At least one of the extraction apparatuses 21-26 is an extraction cell 10 of the type described in relation to Figure 1. In fact, any number of the extraction cells 10 can be used in such a system, depending on the degree of reaction that is desired. The heating may be continuous, or it may be set to provide the desired temperature and pressure in each of the cells 10, depending on the desired degree of reaction at each stage.

Using the previously described system, extraction of coffee beans at 180°C with microwave induced pressure and temperature may provide an extraction yield of 39% soluble solids with extraction of whole roast beans.

S

Although the specific embodiment described herein relates to coffee extraction, the skilled person would appreciate that the concepts contained herein could be easily applied to other forms of beverage extraction, for example chocolate slurry extraction.

Claims

<claim-text>CLAI MS1. An apparatus for beverage extraction, comprising: an extraction cell defining a chamber for containing an extractable material; an inlet for water to enter the extraction cell an outlet for water to leave the extraction cell; and a heat source configured to heat water inside the extraction cell.</claim-text> <claim-text>2. An apparatus for beverage extraction according to claim 1, wherein the heat source comprises a source of microwave energy - 3. An apparatus for beverage extraction according to claim 1, wherein the heat source comprises an oil jacket.4. An apparatus for beverage extraction according to any one of the preceding claims, wherein the beverage is soluble coffee and the extractable material is coffee grounds.5. An apparatus for beverage extraction according to any one of the preceding claims, wherein the beverage is a soluble chocolate beverage and the extractable material is chocolate slurry.6. A system for beverage extraction, comprising a plurality of apparatuses for beverage extraction, wherein at least one of the apparatuses for beverage extraction is according to any one of claims 1 to 5.7. A method for extracting a beverage, comprising the step of: contacting beverage grounds with water within an apparatus for beverage extraction according to any one of claims 1 to 5; wherein water in the apparatus for beverage extraction is heated by the heat source.</claim-text>