Coffee species

Ara, V., Thaler, H., Studies of coffee and coffee-substitute. XVIII. Dependence of the quantity and composition of a high polymer galactomannan on the coffee species and the degree of roasting, Z. Lebensm.-Unters. Forsch., 161, 143, 1976. (CA85 92 372 d)... 

CA107 Duplatre, A., C. Tisse, and J. Estienne. CAl 19 Identification of Arabica and Robusta (coffee) species by studying the sterol fraction. Ann Falsif Expert Chim Toxicol 1984 77(828) 259-270. 

Mazzafera (1991) examined 28 coffee species for their trigonelline content. For the arabicas it is mainly around 2%, the extremes in other varieties being ca 0.8 and 3.0%, higher than the values generally reported. The differences are probably due to different methods of determination. Stennert and Maier (1994) reported literature values in agreement with their own values of 0.88% (average) for seven green arabicas and 0.67 % for three robustas. 

Figure 6.61 Hypothetical pathway of the conversion of caffeine to methyluiic acids in kucha and some Coffee species.

The coffee plant is a relatively small tree or shmb belonging to the family Rubiaceae. It is often controlled to a height of 3 to 5 meters. Coffea arabica (milds) accounts for 69% of world production Coffea canephora (robustas), 30% and Coffea liberica and others, 1%. Each of these species includes several varieties. After the spring rains the plant produces white flowers. About sis months later the flowers are replaced by fmit approximately the size of a small cherry, hence they are called cherry. The fmit on a tree can include underripe, ripe (red, yellow, and purple color), and overripe cherries. It can be selectively picked (ripe only) or strip picked (predominantly ripe plus some underripe and overripe). 

Numerous organic acids iu coffee iuclude acids of metaboHc origin, eg, acetic lactic, citric, malic, and oxaUc free quiuic acid [77-95-2], and various chlorogenic acid (CGA) isomers that appear to be species specific. 

The two main species of commercial interest in the genus Coffea are Coffea arabica and Coffe a canephora var. robusta. They are conveniently referred to as Arabica and Robusta, respectively. Each genus covers a number of varietals there are at least 13 varieties of Arabica coffees, for example. The genus is in the botanical family of Rubiaceae. 

Coffee is grown in countries situated between the Tropics of Capricorn and Cancer. C. arabica is the most widely grown, but regions where temperature and humidity are rather high have been replanted with C. canephora var. robusta. Robusta coffees are thus the major species grown in the less mountainous regions closest to the equator. 

The two major species of coffee grown commercially are Coffea arabica and Coffe a canephora var. robusta. For ease of reference in the following pages they are described as Arabica and Robusta, respectively. They are mentioned separately because they do show differences in their chemical composition. For example, Robusta contains approximately twice as much caffeine as Arabica. 

In conclusion, it can be seen that coffee is a highly variable beverage in terms of its chemical composition. It seems to be essential that studies of the physiological effects of coffee should include a description of the coffee used. In particular the species of coffee, the methods of bean separation, and roasting could be described. This would reduce the possibility of conflicting reports on coffee attributes, and it will allow us to discover how coffee can best be enjoyed. 

Oliveira, J. C., Amorim, H. V., Silva, D. M., Teixeira, A. A., Polyphenoloxidase enzymic activity of four species of coffee beans during storage, Cientifica, 4, 114, 1976. (CA86 68577z)... 

Foods derived from cocoa beans have been consumed by humans since at least 460 to 480 AD. The source of cocoa beans, the species Theobroma, contains a variety of biologically active components. These include the purine alkaloids theobromine, caffeine, and theophylline. Structurally, they are methylated xanthines and, thus, are often referred to as methylxanthines. Theobromine (3, 7-dimethylxanthine) is the predominant purine alkaloid in cocoa and chocolate. Caffeine (1, 3, 7-trimethylxanthine), the major purine alkaloid found in coffee and tea, is found in cocoa and chocolate at about one eighth the concentration of theobromine. Only trace amounts of theophylline (1, 3-dimethylxanthine) are detected in cocoa and chocolate products. 

The streptococci divide in only one plane. They grow normally in pairs or chains. Depending upon the species, the distal ends of each pair may be lancet-shaped, or flattened at the adjacent sides to resemble a coffee bean. 

The purple speck disease of soybeans is caused by the fungus Cercospora kikuchii, and additional cash crops such as tobacco, com, sugar, and coffee are damaged by fungi from the genus Cercospora [3]. Cercosporin (3, Chart 7.1), initially isolated in 1957 from Cercospora kikuchii and subsequently from other Cercospora species, was found to be the phototoxin responsible for the destructive nature of the pathogen [4]. For these reasons, the natural product was extensively studied, yet its structure was not elucidated until the 1970s [5]. 

The coffee of commerce is from the nutlike seeds called beans, that are borne by a tropical evergreen tree, with glistening and waxy surfaced, broad leaves. The seeds are two to a fruit, in pairs, and are covered with a thin, usually red flesh, that makes a cherrylike fruit. There are said to be 50 to 80 different species of coffee. It is still a profitable field of botanical study. At present three species of the tree produce coffee of commerce. 

Coffea arabica L. produces coffee of the best quality and it is by far the most important species. It is composed of several varieties that have developed spontaneously in the past a few new ones are being found at the present time. These varieties include Arabian, Mokka, Maragogipe, and such types, which produce the costly mild flavored coffees. This species is the most delicate, and is almost the only one... 

From Coffea canephora Pierre is obtained a coffee of lower quality, more commonly spoken of as Robusta, Uganda, or Quillou. It is a vigorous tree, second in importance to C. arabica, and has taken its place where diseases and pests prevent the more delicate species from growing. It is a much larger tree, has a wide spread, and when unpruned may reach 18 to 20 feet in height. The trees are planted about 10 by 10 feet and average about 435 to the acre. 

Coffea dewevrei De Wild, is considered by some to produce coffee of even lower quality than Robusta. In some places it has replaced Robusta and can sometimes be grown by native populations where the other two species fail. It is of the least importance to world commerce. The trees are large leaved and often called Liberica and Excelsa. The trees grow to over 30 feet in height if not pruned and are planted about 12 by 12 feet, averaging close to 302 to the acre. 

However, Arabian coffee is the great coffee of history and of commerce. It is the best liked and it is upon this species that the world largely depends. It is in large measure the coffee that has been given most careful scientific attention with respect to control of diseases, insects, and weeds. It is mostly from studies on this species that the information presented here comes. 

The rust of coffee (Hemileia vastatrix B. and Br.) is the most dangerous, most feared, and most troublesome disease of the crop in the world. It does not occur in the Western Hemisphere at present, but it is found in all of the most important Eastern Hemisphere coffee countries and is serious in about 20 of them. It has always been most severe on common commercial varieties of the Arabian coffee. It occurs on other species, such as the Canephora or Robusta, and has always been present on it although in less intensive amounts—for example, in Uganda (70) and in many other countries (93, 99, 103). It also attacks the Dewevrei or Liberica coffee, but the injury is of comparatively minor degree. 

These insects have attendant ants that relish their honeydew, protect them from predators, keep them clean, and move them from old to new tissues when the older stems harden or become exhausted from too much insect feeding. There are several species of these sucking insects, distributed wherever coffee is grown. They have even caused damage in Hawaii, which is almost free from coffee pests. 

The coffee thrips (Diarthrothrips coffeae Williams) is almost microscopic in size. The genus to which it belongs is well known for several species that cause... 

Peterson SW et ai, Penicillium coffeae, a new endophytic species isolated from a coffee plant and its phylogenetic relationship to P. fellutanum, P. thiersii and P. brocae based on parsimony analysis of multilocus DNA sequences, Mycologia 97 659-666, 2005. 

In 1979, we decided to extend our studies to one of the agroecosystems of greater Importance in Mexico the coffee plantations. These studies were realized within the Program of Agroecosystems at the-Institute Nacional de Investigaciones sobre Recursos Bioticos. We worked at the coffee plantations in Coatepec, Veracruz, which are characterized by the presence of shade trees which resemble the structure of the deciduous temperate forests, with three well defined strata the herbaceous layer, the shrub layer represented by coffee plants and the tree layer. The main objective of this study was to assess the allelopathic interactions among the species that constitute this community, in particular the coffee plants (19). 

In contrast with the seed caffeine of Coffea species, relatively little attention has been paid to that of tea. This is in part because the fruit of tea, including the seeds, is of minor economic importance compared with that of coffee moreover earlier studies revealed little caffeine in the tea seed (13.141. Recently we (H) found that the pericarp contains the greatest concentrations of alkaloids in the dry fruit of tea, and that appreciable amounts occur in the seeds, especially in the coats. Thus, from physiological and ecological viewpoints, our concerns are the roles of purine alkaloids and seed coats of tea during fruit development (seed formation) and seed germination. Caffeine in Coffea arabica seed is synthesized in the pericarp, transported to the seed, and accumulated there during fruit... 

The Coffee (syn. Madder) botanical family (Rubiaceae Juss.) (Table 15) consists of more than 400 genera and over 6000 species. It grows in the tropics and the sub-tropics. Plants belonging to this family include trees, bushes and liane. The Coffee plant family contains two major purines of adenine- /guanine-derived alkaloids, the so-called purine alkaloids . Purine is a nitrogenous base of nucleotide, which consists of just purine and pentose sugar (o-ribose or 2 deoxy-D-ribose). Typical purine alkaloids are caffeine, theophylline and theobromine. The same or similar purine alkaloids occur also in other plant families. 

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