Abstract: An improved method for extracting caffeine from a coffee material, preferably raw coffee solids, with an extractant comprising supercritical carbon dioxide. Caffeine is continuously absorbed from the extractant with an aqueous wash solution in an absorber. This wash solution is continuously treated by reverse osmosis to form a caffeine-containing retentate stream and a permeate stream containing dissolved solids but substantially no caffeine. The permeate stream is recycled and used as wash water in the absorber or is used to prehydrate solid coffee materials, or both. The permeate stream comprises acidic dissolved solids.

Abstract: A microwave brewing device for producing freshly percolated measured quantities of coffee, and more particularly, a percolating device which is adapted to percolate coffee within a microwave oven. An open cup is adapted to be filled with water up to a specific level and volume adequate to brew at least a single cup of freshly percolated coffee beverage. The cup or the percolating device therein may be shielded with a shielding material which is impervious to the passage of microwave energy, and only the lower portion of the cup or percolating device may be provided with a gap or constituted of a microwave-transparent region permitting the passage therethrough of microwave energy in order to heat the water contained in the cup wherein the latter is positioned in the cavity of a microwave oven.

Abstract: The present invention relates to a process to recover beneficial coffee volatiles such as diacetyl and acetaldehyde from an aroma stream generated by the thermal hydrolysis of spent grounds. The aroma stream is passed over a bed of a non-polar microporous adsorbent and effluent is collected until breakthrough of furfural is detected. The invention also relates to the composition of the recovered/purified coffee aroma and to soluble coffee products containing the coffee aroma.

Abstract: A method of continuously decaffeinating moistened, green coffee solids with supercritical carbon dioxide. Moistened, green coffee beans are moved periodically through an extraction vessel and contacted with continuously flowing supercritical carbon dioxide which extracts caffeine from the moist, green coffee beans. Caffeine is removed from the supercritical carbon dioxide by counter-current contact with wash water in an open vessel. The caffeine-depleted supercritical carbon dioxide is recirculated back to the extraction vessel and the caffeine-bearing wash water is subjected to concentration by reverse osmosis. Acidic, substantially caffeine-free permeate is directed back to the extraction system as wash water, or to moisturize the green coffee beans prior to extraction, or both.

Abstract: The present invention relates to a process to recover beneficial coffee volatiles such as diacetyl and acetaldehyde from an aroma stream generated by the thermal hydrolysis of spent grounds. The aroma stream is passed over a bed of a non-polar microporous adsorbent and effluent is collected until breakthrough of furfural is detected. The invention also relates to the composition of the recovered/purified coffee aroma and to soluble coffee products containing the coffee aroma.

Abstract: A method of extracting caffeine from green coffee beans whereby an essentially caffeine-free supercritical fluid is continuously fed to one end of an extraction vessel containing green coffee beans and caffeine-laden supercritical fluid is continuously withdrawn from the opposite end. A portion of decaffeinated beans is periodically discharged while a fresh portion of undecaffeinated beans is essentially simultaneously charged to the extraction vessel. The caffeine-laden supercritical fluid is fed to a countercurrent water absorber. Supercritical carbon dioxide is the preferred supercritical fluid. The method of the present invention is more efficient than batch processes and produces an improved decaffeinated coffee.

Abstract: This invention relates to the use of a salt and/or a mild caustic in solution to increase the relative volatility of aromatics contained in an aqueous stream. The increased relative volatility so achieved enables more efficient concentration of the aromas via distillation. The pH of the aroma-containing aqueous stream does not exceed 7.0 through the addition of the salt or caustic to prevent aroma degradation.

Abstract: An improved method for aromatizing soluble coffee is described which results in a higher fixation of grinder gas aromas on a glyceride substrate and an improved quality jar aroma. The method involves liquid-liquid contact of the water phase, normally drained from equilibrated grinder gas and discarded, with a glyceride to recover valuable coffee aromatics in the glyceride. Further, reflux of liquid carbon dioxide is used to recover yet more valuable coffee aromatics in the glyceride. A 25 to 70% increase in aromatic yield is realized with an improvement to the aromatic quality of the aromatized glyceride and thereby the aromatized soluble coffee.

Abstract: The present invention relates to a method of separately recovering caffeine and non-caffeine solids adsorbed on activated carbon. Activated carbon containing the adsorbed solids is contacted with an aqueous basic solution to elute the non-caffeine coffee solids. The two components are separated. The activated carbon is subsequently contacted with a concentrated aqueous acidic solution to elute the relatively pure caffeine. The two components are separated. The non-caffeine solids in the basic solution may be re-adsorbed onto the activated carbon. Essentially pure caffeine may be refined from the aqueous acidic solution.

Abstract: The process disclosed herein decaffeinates an aqueous caffeine feed solution by contacting it with a multi-phase extractant which comprises a continuous phase of a liquid, water-immiscible, caffeine-specific solvent and discontinuous aqueous phase dispersed therein. The caffeine is selectively extracted from the aqueous feed solution, leaving the solubles necessary for a good testing beverage due to the high combined selectivity of the extractant phases. Very low solvent-to-extract ratios are possible because the multi-phase extractant has a much improved partition coefficient as compared to the water-immiscible solvent.

Abstract: The recovery of caffeine from activated carbon is accomplished according to the present invention by employing an aqueous acetic acid solution, preferably having a concentration of between about 50 and 80%, by weight, and which is capable of competing for the active sites on the carbon occupied by the caffeine to displace at least a portion of the caffeine which is then dissolved in the solvent. After the desired period of contact, preferably at a temperature above 100.degree. C., the caffeine is separated from the solution.

Abstract: This invention is designed to prevent the loss of desirable flavor and aroma volatiles during processing of an aqueous coffee extract obtained from roasted and ground coffee. The overall process of preparing soluble coffee by spray drying a concentrated aqueous extract is improved by employing cold coffee extract in an absorption column to absorb highly volatile coffee flavor and aroma compounds.

Abstract: The process disclosed herein is capable of decaffeinating green coffee beans at a moisture content near that employed for shipping and storage. The green coffee beans are contacted with dimethyl sulfoxide, an aprotic solvent, to remove at least a portion of the caffeine. The caffeine is preferably removed from the solvent by use of a solid adsorbent such as activated carbon.

Abstract: The process described herein improves the decaffeination of both wet and dry green coffee beans with a liquid or supercritical carbon dioxide extractant by dissolving dimethyl sulfoxide in the extractant prior to contact with the beans. Rates of extraction are greatly improved, especially in the preferred mode where the dimethyl sulfoxide is employed at near saturation levels.

Abstract: The process disclosed herein decaffeinates an aqueous caffeine solution by contacting it with a solid caffeine adsorbent which is made more selective to caffeine by a thin layer of a water-immiscible, caffeine-specific solvent. The caffeine is selectively extracted from the aqueous solution, leaving the solubles necessary for a good tasting beverage, by the solid adsorbent. Because the solvent is selective, the coated adsorbent likewise shows selectivity.

Abstract: The object of the invention is to provide an improved process for recovering caffeine adsorbed on activated carbon.Caffeine removed from the commercial decaffeination of vegetable materials and extracts can be effectively removed from the extraction solvent, or can be purified, by the use of activated carbon. Unfortunately, the caffeine is tenaciously held by the carbon and none of the techniques currently available for removing the caffeine is wholly satisfactory.The recovery of caffeine from activated carbon is accomplished according to the present invention by employing a liquid, food-grade caffeine solvent which comprises an organic acid or alcohol, and which is capable of competing for the active sites on the carbon occupied by the caffeine to displace at least a portion of the caffeine which is then dissolved in the solvent. After the desired period of contact, the caffeine is separated from the solvent.

Abstract: Liquid propane, liquid butane or mixtures thereof at a temperature of from 30.degree. C. to 95.degree. C. is employed to selectively remove caffeine from moistened green coffee. The resulting decaffeinated coffee is then roasted and processed to ground or soluble coffee products which will possess the flavor and aroma of comparable non-decaffeinated coffee products.

Abstract: A high quality coffee extract is prepared using a commercial percolation system utilizing a superficial velocity of aqueous extraction liquid past the roasted and ground coffee of at least about 0.50 ft/min in the fresh stage extraction column of a percolator set.

Abstract: This invention involves applying a warm coffee extract onto a freezing surface in a plurality of layers until a desired thickness is obtained. Thus applied, there is continual melting and refreezing of the extract. This permits the formation of large ice crystals whereby the finished product is darker and more coffee-like in color. Overall efficiency of the freezing process is also increased allowing higher productivity rates.

Abstract: An improved coffee percolation process is disclosed whereby improved yields of soluble coffee solids are obtained from roasted and ground coffee. The extraction columns of the percolator set are loaded with roasted and ground coffee such that there is a continually decreasing average particle size in the direction of flow of the extraction liquid.