WO1997007686A1

WO1997007686A1 - Decaffeination of coffee

Info

Publication number: WO1997007686A1
Application number: PCT/US1996/013374
Authority: WO
Inventors: Robert Lehrer
Original assignee: Robert Lehrer
Priority date: 1995-08-28
Filing date: 1996-08-19
Publication date: 1997-03-06
Also published as: AU6954096A

Abstract

A coffee bean extract or consumable coffee extract is decaffeinated by treating the extract with an inorganic silicate or aluminate material (18) which has been conditioned to act as a high capacity adsorbent or scavenger. The material is preferably an inorganic clay mineral such as bentonite.

Description

DECAPFEINATION OF COFFEE

Cross-Rβference to Related Application

This application is based upon Provisional Application Serial No. 60/002,838 filed August 28, 1995.

Background of the Invention

Various techniques have been suggested for the decaffeination of coffee. It would be desirable if such decaffeination could be accomplished without the use of potentially harmful organic chemicals as is done in conventional techniques. iiitima y of the Invention

An object of this invention is to provide techniques for decaffeinating coffee.

A further object of this invention is to provide such techniques which avoid the use of potentially harmful organic chemicals.

In accordance with this invention the decaffeination is accomplished by treating a coffee bean extract or the consumable coffee extract with an inorganic aluminate or silicate material, such as a clay mineral or a non-clay mineral, or other suitable non-mineral adsorbent, which has been additionally conditioned to act as a high capacity adsorbent or scavenger or ion-exchange agent. The Drawings

Figure 1 is a top plan view of a ilter device which may be used in the practice of this invention;

Figure 2 is a cross-sectional view taken from Figure 1 along the line 2-2;

Figure 3 is a cross-sectional view in elevation showing the device of Figures 1-2 mounted in place;

Figure 4 is a view similar to Figure 2 of a modified form of device;

Figure 5 is a cross-sectional view taken through Figure 4 along the line 5-5; and

Figure 6 is a cross-sectional view similar to Figure 5 of still yet another device useable in the practice of this invention.

Detailed Description

This invention involves treating a coffee bean extract (extracted using water or another inorganic or an organic liquid) or the consumable coffee extract resulting from any coffee brewing process (normally using hot water) with an inorganic silicate or aluminate clay mineral or non-clay mineral such as a bentonite or a zeolite which has been itself conditioned to act as a high capacity adsorbent or scavenger or ion-exchange agent for materials such as caffeine or the like. Instead of a clay or non-clay mineral, the conditioned material may be a non-mineral.

Specifically:

1. A clay or non-clay mineral—a bentonite—is stirred with a combination of >1 Molar inorganic Acids (Hydrochloric and Nitric) at elevated temperature (about 80° C.) for up to several hours. This acid treatment is useful in enhancing the ability of the bentonite to be a good adsorbent and/or ionic exchange agent and/or a scavenger for certain metals and certain chemical compounds of interest such as caffeine.

2. The acid treatment is followed by a thorough wash with hot distilled deionized water + several cool water rinses.

3. Extracts from coffee beans, or those resulting from brewing coffee, when placed in contact with the prepared bentonite material, either in slurry fashion or through a filter device (such as de¬ scribed in U.S. Patent 5,304,305, all of the de¬ tails of which are incorporated herein by reference thereto) in which a "pocket" or "pockets" contain the bentonite, are acted upon in such a manner that a substantial quantity of caffeine or like sub¬ stance is taken up and held by the bentonite in a way that is irreversible under the conditions used.

4. Analytical High Performance Liquid Chromatography (HPLC) testing has been used to quantitate caffeine levels; the data to date show reductions up to 100%; specific results are dependent upon factors such as starting caffeine content, contact time, bentonite quantity and capacity and clay or non- clay mineral type or non-mineral type. 5. There are no "organic chemicals" used in this decaffeination process; this is a distinct advan¬ tage over current widely used methods. Figures 1-2 show a filter type device 10 similar to that described in U.S. Patent No. 5,304,305. As shown therein device 10 includes an upper layer 12 and a lower layer 14. Pockets 16 are formed between the layers as best shown in Figure 2 in the centrally located fluid contact region. The pockets are filled with the decaffeinating material 18. The pockets are designed so as to provide a sufficient quantity of decaffeination material 18 to decaffeinate up to the maximum volume of coffee bean extract capable of preparation in one coffee brewing operation.

Figure 3 shows the device 10 mounted in a basket 20 of the type conventionally used for brewing coffee. As shown therein coffee beans 22 would be placed on the filter device 10 directly above the pockets 16. When hot water is poured into basket 20 the coffee extract would be treated by flowing through pockets 16 into contact with the bentonite or other decaffeinating material 18.

Figures 4-5 show a variation of treating device wherein the device 30 includes a pair of layers 32,34 sealed together at annular juncture area 36 to form a single enlarged pocket 38 in the centrally located fluid contact region which, in turn, contains the decaffeinating material 40. Figure 6 shows a variation of treating device 50 which combines features of devices 10 and 30. As shown therein a three layer device is provided from layers 52, 54 and 56. A single enlarged pocket 58 is formed between layers 52 and 54 while a plurality of pockets 60 are formed between layers 54 and 56. All of the pockets could contain decaffeinating material or the decaffeinating material 62 could be, for example, in the single pocket 58 with other beneficial functional filter material 64 in the smaller pockets 60. Instead of or in addition to filter material, flavor enhancing material such as disclosed in co-pending application Serial No. 239,581 filed May 9, 1994, all of the details of which are incorporated herein by reference thereto, could be incorporated in the smaller pockets. Alternatively, the decaffeinating material could be in the smaller pockets 60 and other beneficial/functional the filtering and/or flavor enhancing material in the single large pocket 62. When used in a basket layer 52 could be uppermost or layer 56 could be uppermost.

The layers are preferably impervious to the flow of liquid except in the areas of the pockets. As a result there is assurance that the flow of liquid will be confined through the pockets thus assuring intimate contact of the liquid and extract with the material in the pockets. This can be accomplished by having all of the layers liquid impervious except at the pocket area or by having only a single layer liquid impervious except for the pocket areas. The invention could be broadly practiced however where the layers are pervious to liquid flow throughout without having any impervious portions; although this does not assure the highest degree of contact with the decaffeinating material as in treating members which are pervious only in the area of the pockets.

It is to be understood that the decaffeinating member which contains the conditioned clay mineral or non-clay mineral material may take other forms than illustrated herein. Thus, for example, a version similar to Figure 6 could be provided except that the decaffeinating material could be in a single big pocket and the treating material in an associated big pocket rather than in smaller individual pockets. Alternatively, two sets of smaller individual pockets could be provided between the first layer 52 and second layer 54 and between the second layer 54 and third layer 56 with decaffeinating material in one set and treating material in the other set of pockets.

The invention may be practiced to further decaffeinate coffee which purportedly has already been decaffeinated. In this respect, there are commercially available coffees which are represented as being decaffeinated when in fact the coffee still contains some degree of caffeine. The invention may be practiced to remove such caffeine from the "decaffeinated coffee".

Claims

What is claimed is.

1. A method of decaffeinating coffee without the use of organic chemicals comprising providing a coffee extract, condition¬ ing a clay mineral or non-clay mineral material to render the material to be capable of functioning as a high capacity adsorbent or scavenger or ion-exchange agent, treating the coffee extract with the conditioned material by contacting the coffee extract with the conditioned material, and removing caffeine from the coffee extract as a result of the treating step.

2. The method of Claim 1 wherein the coffee extract is a coffee bean extracted by use of a liquid.

3. The method of Claim 1 wherein the coffee extract is a consumable coffee extract resulting from a coffee brewing process.

4. The method of Claim 3 wherein the consumable coffee extract results from a coffee brewing process using hot water with a conditioned clay mineral or non-clay mineral material.

5. The method of Claim 4 wherein the material is bentonite.

6. The method of Claim 1 wherein the material is bentonite.

7. The method of Claim 1 wherein the material is conditioned by being stirred with at least one inorganic acid at elevated temperature.

8. The method of Claim 8 wherein the acid treated material is washed with hot distilled deionized water and with cool water rinses.

9. The method of Claim 8 wherein the material is bentonite, and the organic acids are hydrochloric acid and nitric acid.

10. The method of Claim 1 wherein the material is located in spaced pockets of a multilayer treating member, and the coffee extract contacts the material by passing through the pockets.

11. The method of Claim 10 wherein the treating member has an upper surface which is liquid impermeable except for the location of the pockets to confine the flow of coffee extract through the pockets.

12. The method of Claim 1 wherein the coffee extract is coffee which had previously been decaffeinated.

13. A method of decaffeinating coffee extract without the use of organic chemicals comprising providing a coffee extract, conditioning a non-mineral material to be capable of functioning as a high capacity absorbent or scavenger or ion-exchange agent, treating the coffee extract with the conditioned material by contacting the coffee extract with the conditioned mineral, and removing caffiene from the coffee extract as a result of the treating step.

14. A decaffeinating member comprising at least two layers secured together to form a unit, said unit having a fluid contact region, at least one pocket formed between said layers at said fluid contact region, said unit being liquid pervious at the location of said pocket, and a conditioned inorganic silicate material capable of functioning as a high capacity adsorbent or scavenger or ion exchange agent for comprising a decaffeinating means being in said pocket.

15. The member of Claim 14 wherein said unit is liquid impervious at said fluid contact region except for the location of said pocket.

16. The member of Claim 15 wherein a plurality of said material containing pockets are between said layers.

17. The member of Claim 16 wherein said two layers comprise a first layer and a second layer, a third layer being secured to said second layer, at least one pocket between said second layer and said third layer, and treating material being in said at least one pocket between said second layer and said third layer.

18. The member of Claim 14 wherein a plurality of said material containing pockets are between said layers.

19. The member of Claim 14 wherein said two layers comprise a first layer and a second layer, a third layer being secured to said second layer, at least one pocket between said second layer and said third layer, and treating material being in said at least one pocket between said second layer and said third layer.