Coffee patents

CA084 Gal, S. and E. Jenny. Extraction of the irritating substances from crude coffee. Patent-Swiss-568,719 1975. 

This patent on a three step tea decaffeination process is included in chronological order with the coffee patents because of its similarity to U.S. 3,843,824 which describes a three-step process for the decalfeination of roasted coffee. In the first step, tea aromas are removed from dry tea using dry supercritical CO2. In a next step, the tea is moistened and moist CO2 is passed through the tea to extract the catfeine. In a third step the aromas are returned to the moist tea in the following manner. The aromas are dissolved into a sU eam of supercritical CO2 which is then passed first through a heat exchanger to liquify the CO2 and then to the vessel containing the tea which is now dried. When the tea vessel is filled with the solution of liquid CO2 and the aromas vapor CO2 is withdrawn from the vessel and the aromas precipitate into (and onto) the tea. 

Instant coffee is the dried water-extract of ground, roasted coffee. Although used in Army rations as eady as the U.S. Civil War, the popularity of instant coffee as a grocery product grew only after World War II, coincident with improvements in manufacturing methods and consumer trends toward convenience. Extensive patent Hterature dates back to 1865. Instant coffee products represented 15% of the coffee consumed in the United States in 1991 (31). 

Decaffeinated coffee products represented 18% of the coffee consumed in 1991 in the United States (31). Decaffeinated coffee was first developed commercially in Europe about 1900. The process as described in a 1908 patent (35) consists of first, moisturizing green coffee to at least 20% to facilitate transport of caffeine through the cell wall, and then contacting the moistened beans with solvents. 

Methylene chloride is probably the most generally used solvent for decaffeination processes, but others, some of which are already found in small amounts in coffee beans, are coming into use. For example, ethyl acetate,8 formaldehyde-dimethylacetal, ethanol, methanol, acetone,9 propane,10 benzyl alcohol,11 carbon dioxide,12 and supercritical carbon dioxide with an acid13 are used. Generally the pressure and temperature of the system are adjusted to keep the solvent in the liquid state. Coffee oil itself is even described for this use in one patent.14... 

The presence of tocopherols,114 as well as caffeic acid,108 accounts for the remarkable stability of green coffee bean oils toward oxidation. In coffee beans from different origins, a-tocopherol concentrations are in the range 89 to 188 pg/kg and (p + y)-tocopherol concentrations are in the range 252 to 530 pg/kg.114 Since p- and y-tocopherols have better antioxidant properties than a-tocopherol,114 it is not surprising to see coffee oil patented as an antioxidant material.115117... 

Winkelmann, M., Roebert, L., Arndt, T. et al. Process for candying of coffee beans, German Federal Republic Patent, DE19902786C1, 2000. 

Wilke, T. and Galke, R, Small roaster for roasting of green coffee beans and similar products, German Patent, DE 19941036 Al, 2001. 

Hatanaka, A., T. Kajiwara and J. Sekiya. Biosynthesis of trans-2-hex-enal in chloroplasts from Thea sinensis. Phytochemistry 1996 15 1125. Matsura, T., T. Tsunoda and M. Arai. Theanine manufacture with tissue cultures of tea. Patent-Japan Kokai Tokkyo Koho-03 187,388 1991 7 pp. Takeo, C., H. Kinugass, H. Oosu, T. Kawasaki, N. Takakuwa, M. Shimizu and H. Kondo. Extraction of hyper-glycemics from tea. Patent-Japan Kokai Tokkyo Koho-04 124,139 1992 8 pp. Stalcup, A. M., K. H. Ekborg, M. P. Gasper and D. W. Armstron. Enantiomeric separation of chiral components reported to be in coffee, tea or... 

III. Structural features of pectic acid. An Acad Brasil Cienc 1974 46 357. Buegin, E. Lowering the carboxylic acid-5 hydroxy tryptamide content of unroasted coffee beans. Patent-Ger Offen-2,429,233 1975. 

CAl 51 Myazaki, H. and T. Yamada. Skin cosmetics containing coffee bean extracts. Patent-Japan Kokai Tokkyo Koho-08 301,722 1996. 

Separation of serotonin from coffee wax. Patent-Ger Offen-2,532,308 1976 14 pp. CA206... 

As mentioned in the introduction to this section, there is the opportunity to recover aroma compounds from baking or roasting exhaust gases. The patent literature contains numerous references to the recovery of aroma compounds using this approach, most commonly from cocoa, coffee, or tea processing. Aroma compounds from the roaster exhaust gases are either condensed in cryogenic traps [29-32] or collected on absorbents (e.g. charcoal [33]) and then solvent-extracted to obtain a concentrated aroma extract. The concentrated extract may be used to aromatise a similar product (e.g. soluble coffee) or may be used to flavour other products (e.g. coffee-flavoured ice creams). 

In contrast to the decaffeination of coffee, which is primarily executed with green coffee, black tea has to be extracted from the fermented aromatic material. Vitzthum and Hubert have described a procedure for the production of caffeine-free tea in the German patent application, 2127642 [11]. The decaffeination runs in multi-stages. First, the tea will be clarified of aroma by dried supercritical carbon dioxide at 250 bar and 50°C. After decaffeination with wet CO2 the moist leaf-material will be dried in vacuum at 50°C and finally re-aromatized with the aroma extract, removed in the first step. Therefore, the aroma-loaded supercritical CO2 of 300 bar and 40°C will be expanded into the extractor filled with decaffeinated tea. The procedure also suits the production of caffeine-free instant tea, in which the freeze-dried watery extract of decaffeinated tea will be impregnated with the aromas extracted before. 

Ricker and Spence Powders. Blasting expls based on K chlorate patented in Engl in 1862 by Ricker and Spence. Other ingredients could include K, Na or Pb nitrates, charcoal, algae (partly calcined), Na bicarbonate, wheat flour, pulverized bark and dried coffee residues See also under this title in Vol 2, C206-L Ref Daniel (1902), 683... 

A significant development in supercritical fluid extraction was Zosel s patent for decaffeination between 1964 and 1981, which reported a procedure for the decaffeination of coffee beans with C02 [6-10]. Also, a number of patents of some food companies have been reported that concern the decaffeination of coffee [11]. The American Food Company, for example, has constructed an extraction vessel 7 ft in diameter and 70 ft tall for supercritical C02 decaffeination of coffee at the Houston, Texas plant. The current annual U.S. market for decaffeinated coffee is 2- 3 billion [4]. 

On the other hand, there are numerous chemicals disclosed in patents which may be used to modify and reinforce the aroma and flavor of coffee and beverages. Better understanding of precursors and routes by which important and typical aroma and flavor components are formed is essential to decrease undesirable, non contributing components and improve the acceptance and wholesomeness of this attractive beverage. 

In roasted coffee similar reactions seem to be involved forming methylmercaptan by the Strecker degradation of free methionine and forming H S from peptide cysteine. Figure 8 presents additional flavor contributing constituents of roasted coffee. 3-Thiolanone 6 and 2-methyl-3-thiolanone 1 were identified by Stoll et al. (19) and patented as coffee flavors. The two thiolanones 6, T are formed as major constituents in erythrose and xylose/ cysteine model systems, respectively. 

Being volatile, the aldehydes formed in the Strecker degradation have often been thought to be important contributors to the aroma of foodstuffs and many patents have been granted which use the Strecker degradation to produce flavouring materials of various types, such as, maple, chocolate, coffee, tea, honey, mushroom, and bread.66... 

Miscellaneous. Dried coffee extracts are stabilized if added ascorbic acid is incorporated during their processing (712,713). Ascorbic acid has also been studied in the tea fermentation process (714). Confectionaries (715-721) can be a good vehicle for ascorbic acid, particularly, hard candy (311) because of the presence of fruit acids and low oxygen permeability. Also, ascorbic acid has been added successfully to caramels (312,721), chocolates (312), marron glaces (715), and ice candies (716). A synthetic caviar has been developed and patented, the formulation of which calls for added ascorbic acid (722),... 

The attractiveness of supercritical carbon dioxide extraction is shown by the already existing industrial applications of hop extraction, decaffeination of tea and coffee, defatting of cocoa powder, and extraction of herbs and spices and is also demonstrated by the large number of patent applications and scientific publications in recent years. 

The term supercritical fluid is used to describe any substance above its critical temperature and pressure. The discovery of the supercritical phase is attributed to Baron Cagniard de la Tour in 1822 [3], He observed that the boundary between a gas and a liquid disappeared for certain substances when the temperature was increased in a sealed glass container. While some further work was carried out on supercritical fluids, the subject remained essentially dormant until 1964 when a patent was filed for using supercritical carbon dioxide to decaffeinate coffee. Subsequent major developments by food manufacturers have led to the commercialization of this approach in coffee production. The use of supercritical fluids in the laboratory was initially focused on their use in chromatography, particularly capillary supercritical fluid chromatography (SFC). However, it was not until the mid-1980s that the use of SFE for extraction was commercialized. 

The Katz patent states that about 15% of the coffee beans in the extractor are discharged and admitted during a semicontinuous pulse. To provide an estimate of the scale of the process we here calculate the amount of coffee beans moved during a pulse. The vessel is 70 ft tall X 7 ft diameter this equates to an internal volume of about 2500 ft. Coffee beans have a density of about 40 Ib/ft, so the extraction vessel holds about 100,000 lb of coffee beans. A 15% replenishment is a rate of 15,0001b per pulse, and the pulse happens about every 30 to 60 min—this is not laboratory scale operation. There are still many other hops extraction, coffee decaffeination, and spice extraction plants throughout the United States and Europe several of them operate at 30 to 60 million Ib/yr throughput, further exemplifying that SCF extraction is not just a laboratory curiosity. 

Coffee decaffeination with carbon dioxide has been the object of a large amount of effort in research and development at the Max Planck Institute for Coal Research in Germany and at other academic and industrial laboratories in Europe and the United States. An indication of the intensity of effort applied to this process comes from a review article that lists the United States patents on decaffeination granted up to the end of 1981 (Paulaitis et al., 1983a). Several earlier patents were inadvertently omitted from that list a corrected version is given in table 10.1. Research activity on supercritical fluid extraction of stimulants from coffee, tea, and cocoa has continued, indicated by the number of United States patents granted since that review article was published some of them are listed in table 10.2. 

Each patent has somewhat different features and claims. We select one patent for more detailed discussion to highlight certain technical facets of the process. First we explain the (often misunderstood) effect of water on the extractability of caffeine by selective supercritical carbon dioxide. A number of references report that dry carbon dioxide cannot extract caffeine from dry coffee, either green or roasted, but moist carbon dioxide can. The inability of dry carbon dioxide to extract caffeine from coffee should not be misconstrued to mean that dry carbon dioxide cannot dissolve neat caffeine. This same moist-versus-dry effect is experienced if, for example, methylene chloride is used to extract caffeine from coffee. Dry methylene chloride cannot decaffein-ate dry coffee but moistened coffee can be decaffeinated. It is thought that the caffeine is chemically bound in a chlorogenic acid structure present in the coffee bean. Thus, water somehow acts as a chemical agent it frees caffeine from its bound form in the coffee matrix in both the carbon dioxide and the methylene chloride processes. 

Table 10.1 United States Patents on Coffee Decaffeination (1981 and Earlier)...

We summarize the data from one example of an early coffee decaffeination patent to highlight the specifics of the process (Roselius, Vitzthum and Hubert, 1974). Four hundred grams of rough-ground deoiled roast coffee is wetted with 200 ml of water and is treated with supercritical CO2 with an... 

---