Coffee N.F. USD 1926
COFFEA TOSTA. N. F. COFFEE Coff. Tost. [Roasted Coffee]
Coffeeis the dried ripe seed of Coffea arabica Linne or Coffea liberica Bulliard Fam. Rubiaceae deprived of most of the seed coat and roasted until a dark brown color and characteristic aroma are developed.
Coffeeyields not less than 1 per cent, of caffeine, not less than 3 per cent, and not more than 5 per cent, of total ash, and not less than 10 per cent, of fat." N.F.
Coffee, Semen Caffese; Kaffee, G.; Caf�, Fr.; Caffe, It.; Caffi, Sp.; Bun, Ar.; Copi Cotta, Singhalese; Kaeva. Malay.
Coffea arabica L. and C. liberica Bull,are small evergreen trees with opposite, oblong-ovate, acuminate leaves of leathery texture, axillary clusters of white, tubular flowers and globular, red to purplish, berry fruits. The coffee berries are about the size of a cherry. Each of these consists of a 2 celled pericarp surrounding 2 plano convex seeds. The seeds are longitudinally grooved on their plane surfaces and enveloped by a thin membranous endocarp called "parchment." Between each seed and the parchment is a thin covering called "silver-skin." When divested of their coverings they constitute coffee.
Coffea arabica is indigenous to Abyssinia, while C. liberica is native to Liberia. C. robusta has been cultivated in Java. For description see Vichoever and Lepper (J.Assoc.Off.Agr.Chem.,1921, v, 274).
Aboutthe year 1690 coffee was introduced by the Dutch from Arabia into Java, and in 1718 into their colony of Surinam. Soon after this latter period the French succeeded in introducing it into their West India islands, Cayenne, and the Isles of France and Bourbon. Within a comparatively short time coffee cultivation was taken up by many other tropical countries of the western hemisphere.
To-day the coffee plants are extensively cultivated in Arabia, Java, South America, Central America, Mexico, West Indies, India and Hawaii. Brazil and Java are the largest producers, Brazil giving to the world about 80 per cent, of all the coffee produced.
The coffee trees are grown from seeds which, when sown in properly prepared soil, germinate in less than a month. Within a year the young plants are transplanted and set out at suitable distances. They yield mature fruits in two or three years but generally require five years before bearing a good crop and continue to be productive for thirty to thirty-five years. Two crops are generally harvested each year. The fruits are gathered when fully mature and prepared for the market by either the dry or wet methods.
The dry method is the more primitive and at present almost restricted to Arabia which yields much of the Mocha coffee. It consists of spreading the fruits out in a thin layer on a drying floor and exposing them to the drying action of the sun. Later the pulp and parchment are removed, liberating the two seeds contained in each fruit. In the wet or West Indian method which is the one now most generally employed, the fruits are placed in a tank of water. The mature fruits sink and are drawn through pipes to a pulping machine where the fleshy portion is reduced to a pulp, and the pulp and free seeds, enclosed in their membranes, conveyed to a second tank of water. Here they are stirred, the pulp being separated by washing and the seeds sinking to the bottom. The parchment membranes are removed by allowing them to slightly ferment and by washing, accompanied by trampling with bare feet and stirring. The seeds are then dried in trays, or barbecues, by natural or artificial heat. In this condition they constitute "raw coffee." They are subsequently graded by passing them through sieves having large, medium and small apertures. They are then garbled to remove split or otherwise defective seeds and foreign matter. They are usually packed in bags and imported in the unroasted condition.
The finest coffee grown is that commercially known as "Java coffee " from the East Indies, mostly from Sumatra. Mocha coffee is a sharp, aromatic type which is grown in Arabia; little of it comes to this country. The chief varieties or types of coffee grown in Brazil are those designated commercially as "Santos Rio," "Mocha Seed Santos" and "Victoria."
Raw coffee has a faint, peculiar odor and a slightly sweetish, somewhat harsh taste.
During the roasting process coffee swells to almost double its original volume, losing from 15 to 23 per cent, of its weight, and acquires a new, peculiar odor and a bitter taste. An active empyreumatic oil (caffeol, C8H10O2) is developed during the process, probably at the expense of a portion of the caffeine. Much of the alkaloid, however, escapes change, and a portion of it is volatilized. The excellence of the flavor of roasted coffee depends much upon the manner in which the process is conducted, and the extent to which it is carried. It should be performed in a covered vessel, over a moderate fire, and the grains should be kept in constant motion.
When they have acquired a chestnut-brown color, the process should cease. If too long continued, it renders the coffee bitter and acrid, or, by reducing it to charcoal, deprives it entirely of flavor. During a severe roasting the coffee loses a portion of caffeine, which sublimes, while in a slight roasting it loses none, yet ordinary coffee for drinking, prepared by percolation, contains rather more caffeine when prepared from strongly roasted than from slightly roasted coffee, because the caffeine is more easily extracted from the former. Paul and Cownley found in preparing " low and medium roasted " coffee no perceptible loss of alkaloid, while in " over roasted " coffee the loss amounted to one-third. The average of caffeine in roasted coffee they give as at 1.3 per cent. (P. J., 1887, 822.)
Parry (Food and Drugs, vol. i, 1911, p. 31) gives the following comparative figures for coffee before and after roasting;
Seissir has devised a method for removing the caffeine from coffee. About 5 kilos of unroasted coffee berries are placed in a closed centrifugal drum which is surrounded by a hot-water jacket. After the addition of about 15 kilos of ethyl acetate, the drum is set in motion, so that the solvent and berries are thoroughly mixed, the temperature being maintained at 68� C. At the end of three hours the solvent is drawn off, and replaced by a further quantity of about 10 kilos, and the mixing and extraction are continued for a further two hours. The ethyl acetate is then run off, the berries are heated to 100� C.
to remove the last traces of solvent, and finally dried at 40� to 46� C., the drum being rotated meanwhile. The ethyl acetate may be recovered by distillation, and the caffeine separated from the residue. The method is the subject of a French patent. (/. Soc. Chem. Ind., 1909, 622.)
Description and Physical Properties.
Powdered Coffee � Numerous fragments of the seed coat made up of parenchyma and irregular stone cells, the latter up to 1,000 mm. long and up to 0.135 mm wide, with walls having simple pores; numerous brownish endosperm cells having porous walls about 0.010 mm. thick and containing oil and aleurone grains; starch grains few or absent; reticulate trachea wanting.
Percolate 1 Gm. of powdered Coffee with ether until exhausted and evaporate the percolate to dryness; the residue weighs not less than 0.1 Gm. (presence of at least 10 per cent, of fat). Boil 1 Gm. of powdered Coffee with 10 cc. of distilled water, filter and acidify the filtrate with 1 cc. of diluted sulphuric acid, and then decolorize it by the cautious addition of potassium permanganate T.S. This decolorized solution shows no blue or purple coloration upon the addition of iodine T.S. (starch) Shake 1 Gm. of Coffee with 20 cc of water; the strained liquid shows no colored or heavy deposit. Shake 1 Gm. of Coffee with 20 cc. of alcohol; the strained liquid shows no colored or heavy deposit nor is any color imparted to the alcohol (artificial colors or facings).
Assay � Place 6 Gm. of Coffee, in fine powder, in a suitable flask or bottle, add 120 cc. of chloroform and shake. Allow to stand five minutes, then add 6 cc. of ammonia water and shake the mixture continuously during one hour, or intermittently (see Proximate Assays, Type Process A) during two hours. Allow the mixture to stand over night, again shake intermittently during one-half hour, then allow the drug to settle. Decant or filter off through a pledget of purified cotton.
100 cc. of the chloroformic liquid, representing 5 Gm. of Coffee, and evaporate to dryness. Treat the residue with 10 cc. of weak (about 1 per cent.) sulphuric acid with the aid of a gentle heat, allow to cool, filter through a small filter into a separator, and wash the dish and filter with successive small portions of distilled water until no test for alkaloid is obtained by acidulating a few drops of the filtrate strongly with sulphuric acid and adding iodine T.S. Now add ammonia water until the liquid is distinctly alkaline to litmus, and completely extract the caffeine with successive portions of chloroform, as shown by testing with iodine T.S. Evaporate the combined chloroform solutions, and dry the residue at 80� C. to constant weight. The weight is the amount of caffeine from 5 Gm of Coffee." N. F.
Adulterations � Both whole and ground roasted coffee have been and still are adulterated by irresponsible dealers. The whole article has been adulterated with artificial coffee seeds made by moulding and roasting dough as well as masses of pea hulls, ground cereals and molasses. The ground article has been adulterated with the following ground roasted materials: chicory root, identified by its short, pitted and reticulate trachese and dandelion root, identified by its pitted and reticulate tracheas and numerous latieiferous vessels; cereals and cereal products, identified by their hairs, cross cells and starch grains; coffee hulls, characterized by a layer of curved palisade cells with yellowish contents; leguminous seeds, characterized by fragments of palisade cells and typical starch grains; figs, identified by fragments of the mesocarp of receptacle containing abundant branching latex tubes up to 50 /* in breadth, and numerous rosette crystals of calcium oxalate and by numerous small achene�s usually imbedded in the roasted pulp; ivory nuts, identified by the large, endosperm cells with porous walls of reserve cellulose that are up to 35 v- or more in thickness; acorn kernels, identified by their distorted, ellipsoidal or elongated starch grains, each with prominent elongated hilum.
Chicory, dandelion and other similar roots used as adulterants may be detected microscopically, but a chemical method of detection has been proposed by LaWall and Forman (J. A. Ph. A., 1914, iii, p. 1669), which depends upon the determination of the ratio of reducing sugars to extractive matter in the aqueous decoction.
Mwssaenda coffee, so called, is not a true coffee, but the seeds of Gaertnera vaginata Lam. (Fam. Loganiacea). (P. J., Nov., 1889.)
C. Griebel (Nahr. Genussm, 1918, xxxv, 272) finds among the numerous coffee substitutes chicory and beets play the main role. In addition, however, waste products have been used, like potato pulp, husks of grapes or other fruits, tree bark, the stony part of fruit shells and kernels or stone fruits of plants such as Hawthorne, rose, etc. Spurry as well as locust seeds (see Robinia, Part II) have been used as coffee substitutes, and Griebel discusses them in detail. Spurry (Spergula arvensis, Fam. Caryophyllacece), growing quite generally as a weed on sandy soil, is under cultivation for feed in western Germany.
Constituents � The most important substances present in raw coffee are: the alkaloid caffeine, a peculiar tannin, and a sugar, probably glucose, which is almost completely caramelized in the roasting process. Caffetannic acid has been ascertained by Hlasiwetz to be a glucoside with the formula C14H8O7 and resolvable into glucoside and a peculiar crystallizable acid, C8H8O4, named by him caffeic acid (J. P. C., 1867), and which may be obtained from coffee by boiling a solution of the extract with potassium hydroxide, treating the resulting liquid with sulphuric acid in excess, and extracting the caffeic acid with ether, which yields it somewhat impure by evaporation. (J. P. C., 1868, 75.) Julian E. Walter (Ph. Bee., May 5, 1890, 176) found the percentage of caffeine in various samples of unroasted coffee to range from 0.54 to 1.24 per cent. Bertrand (Butt. Sc. Pharm., iv) gives the following results of studies of the percentage of caffeine in various coffee berries: In Coffea arabica the percentage varied from 0.69 to 1.60; C. canephora was found to be rich in alkaloid, the berries yielding 1.97 per cent., while those of the C. humboldtiana, Baill., were remarkable by reason of their containing a bitter principle, cafamarin, but no caffeine at all; the berries of C. mauritiana contained only 0.07 per cent.
The leaves of the coffee plant possess properties analogous to those of the fruit, and are extensively used by the Malays. Stenhouse found them to contain caffeine in larger proportion than the coffee bean, and also caffeic acid. The leaves are prepared for use by drying over a clear fire and then powdering by rubbing in the hands. The powder is made into an infusion like common tea. The taste is like that of tea and coffee combined. (P. J., xii, 443; xiii, 207 and 382, and xvi, 1067.)
The effects of coffee are due chiefly, if not solely, to the caffeine which it contains. Some writers, however, believe that the volatile oil, caffeol (caffeone) possesses stimulating properties. The evidence of this point, however, is so contradictory as to render conclusions impossible. (See Reichert, M. News, 1890, Ivi; Erd-mann, A. E. P. P., 1902, xlviii; Geiser, A. E. P. P., liii, p. 112.)
Uses � As a medicine coffee has been almost entirely replaced by the alkaloid caffeine. The infusion is, however, sometimes administered by rectal injection in cases of narcotic poisoning. The chief reason for the recognition as a drug is its agreeable flavor. The disturbances of digestion which follow excessive coffee drinking are not considered by J. Burmann to be due to caffeine, but to a volatile toxic substance formed during roasting and only partly volatilized, named cafeotoxin, which can be eliminated by subjecting roasted coffee to successive treatments with steam under pressure of several atmospheres (J. P. C., 1913, 8, 281.)
Dose, thirty to sixty grains (2-4 Gin.). Off. Prep.�Fluidextractum Coffeae, N. F.
Tropical Planting. Sri Lanka.
H.F.Macmillan, F.L.S., A.H.R.H.S.
Coffee. Caff�, Kap-pe, Kopai, etc.
Coffee has a varied history. About three-quarters of the world's supply now comes from Brazil. Its cultivation in Ceylon, which exported over a million cwt. in 1874, was practically wiped out by the Coffee-leaf disease (Hemeleia vastatrix). While, however, the cultivation is dwindling in some countries, in others it has been considerably extended in recent years, notably in Kenya and other parts of East and Central Africa. The market value of coffee fluctuates from 35 shillings. to 85 shillings* or more per cwt., depending on market conditions and quality, the latter being determined by flavour, colour of beans, regular grading, etc. Costa Rica and Jamaica (" Blue Mountain ") coffees command the highest prices, Kenya and S. India coming next. These and similar forms are classed on the market as " Mild Coffee," as distinct from the Brazilian product, which is generally considered a " hard " type and is in a class by itself.
Ed Note :Prices as at 1943, at today�s conversion that is US$3.24 and $8.35 respectively per 112 1bs or 50Kg.
Cultivation. Coffee thrives in a moderately humid atmosphere and prefers deep friable soil on undulating land; it is unsuited to stiff clay or sandy soils, and is considered tolerant of acid soils. The " Arabica " thrives from 1,500 to 5,000 ft. or higher, while the '' Robusta'' type is suited to lower elevations, and the '' Liberica'' to elevations below 2,000 ft. Propagation is by seed sown in nursery beds or, preferably, in basket or bamboo pots. The seed germinates in 5-6 weeks, and the seedlings should be ready for planting out about 10 months later. Spacing should be not less than 7 X 7 ft. for the "Arabica," and about 10 X 10 ft. for the more robust "Liberica" and " Robusta." Shade must be afforded until at least the plants are established; light permanent shade is usually beneficial, if not essential, except perhaps at the higher altitudes and in the case of " Liberica." In Kenya and Uganda shade is not considered necessary, but in India, Java, Arabia, Mexico and other S. American States it is important. Different trees are employed for shade, e.g. Dadap, Mortelle, Grevillea, Albizzia, Acrocarpus, Leucaena, etc. The last-named is favoured in Java, Sumatra and Ceylon, especially in the early stages of the crop. The coffee plants being surface feeders, manuring is indispensable, including green manures and, when available, farmyard manure.
Pruning consists mainly in thinning out weakly or superfluous branches and maintaining the bushes in proper shape, and is carried out after harvesting the crop. The plants should be topped to 2 ft. when about 4 ft. high, so as to form spreading bushes, which may be kept at a convenient height of about 5-6 ft. In India and Ceylon the bushes blossom chiefly in March or April, after the commencement of the rains, the crop being harvested in October-December, i.e. 7 or 8 months later. The flowers are pollinated mainly by bees and other insects.
Yield. The first crop, a small one, is produced when the plants are 3 years old. When in full bearing, at the age of 6-8 years, a yield of about 1-1.5 Ib. of cured coffee per tree, or about 5 cwt. per acre, is considered a good average crop, though in some cases 7-8 cwt. or 2-3 Ib. per tree may be obtained. The bushes may continue to yield for about 30 years or longer. The berries are picked when they turn red, and a good worker can pick 3 bushels or more a day. A bushel of fresh berries will yield about 10 Ib. of marketable coffee, or 5 bushels about 1 cwt. Each berry or "cherry" contains 2 seeds (" beans ") facing each other by their flat sides; sometimes only one sound seed, called "pea berry." About 800 fresh seeds go to a Ib., arid l|-2 Ib. should be sufficient to plant an acre, allowing for possible failures.
Curing. Pulping (i.e. removing the shell or pulp of the berries) is done by a pulping machine soon after the berries are picked. The beans are then fermented for 12-18 hrs. in concrete tanks or wooden boxes in order to remove the saccharine matter and facilitate drying. They are then washed in running water, and dried on a barbecue or on trays placed in the sun. Drying takes about 3 weeks and should be gradual. The beans are then known as Parchment coffee. The parchment or "silver skin" is afterwards removed by hulling, which is either done locally or after export, during which process grading and winnowing are also performed. Sometimes the berries are simply dried whole, being then known as native coffee or dried berry. In this form the superior qualities of the coffee are said to be retained, but the subsequent processes of pulping, etc., are more troublesome and transport is more costly. Coffee owes its stimulating quality to the presence of caffeine, which is similar to theine of tea.
Pests and Diseases. The most serious of these is probably the Coffee-leaf disease (Hemeleia vastatrix). It is considered that moderate shade by means of suitable trees has the effect of maintaining the normal health and vigour of the plants, thus increasing their resistance. Spraying with "Bordeaux Mixture" or other fungicides are the best means of controlling the disease.
Liberian Coffee. (Coffea liberica.)A robust-growing tree, native of W. Trop. Africa, introduced to Ceylon about 1870, distinguished by its considerable height (30 ft. or more if left to itself), large, thick leaves and large berries. The tree does not require shade, bears fruit almost throughout the year, but the product commands a lower price than the " Arabica." The berries do not drop as soon as ripe, as do those of the latter, and have a tougher and more fibrous shell. The vigorous constitution of the tree renders it more or less resistant to the leaf disease, and a Robusta Coffee (Coffea robusla). yield of about 6-8 cwt. per acre may be obtained. Suited to low elevations only, i.e. up to about 2,000 ft. Planting distances may be about 10 X 10 ft. or 12 X 12 ft. The plants should be topped to 2.5 ft. when at a height of about 5 ft.
Excelsa Coffee. (Coffea excelsa).A vigorous species, indigenous to Cent. Africa, with large, handsome leaves. This and Abeokuta Coffee, also of Trop. Africa, are both of the Liberica type and, like the latter, appear to possess considerable powers of disease resistance. The former gave a crop of over 10 Ib. per tree at the Peradeniya Experiment Station, Ceylon, and a similar yield in Trinidad.
Congo or Robusta Coffee. (Coffea robusta = C. Laurentii.)A species indigenous to Cent. Africa, recently brought into cultivation, distinguished by its large, handsome, wavy leaves, introduced to Ceylon in 1900. It has given very satisfactory returns in Malaya as a catch crop with young rubber; thrives at low and medium elevations, yielding a crop of about 1 cwt. per acre 2.5 years after planting, 4-5 cwt. in the 3rd or 4th year, and 6-8 cwt. in the 5th year. 600 seeds go to a pound. Other species (or varieties) of this type are : Uganda Coffee, Canephora, and Quillou, all suited to low or medium elevations and disease-resistant.
Upland Cofee of Sierra Leone. (Coffea stenophylla.)A slender-stemmed, small-leaved W. African tree, reaching a height of about 25-30 ft. if left to itself; bears a profusion of small ovoid berries, which are black when ripe and reported to have a superior flavour. Introduced at Pera deniya in 1894; nourishes and bears an abundant crop, usually in December�January.
Hybrico Coffee.A Brazilian hybrid whose berry contains 4-6, instead of 2, seeds; its quality is well spoken of, but it does not appear to be known in the East.
Maragogipe Coffee,of Brazil, is of a robust habit with large leaves, similar to the Liberica. This has been established at Peradeniya since 1884, but although the tree flourishes here it bears but scanty crops.
Hybrid Coffee.There are several hybrids of Coffee, among the best being a cross between the Arabica and Liberica, which bears heavy crops of good-sized berries. This has yielded an average of 14 Ib. dried berries per tree, for 150 trees, at the Peradeniya Experiment Station, Ceylon. The plant is a vigorous grower, and its robust constitution appears to render it to some extent immune from leaf-disease. Kent's Hybrid is well spoken of in S. India.
Mocha Coffee. The coffee of Arabia and Abyssinia, being exported from the town of Mocha, is generally known in the trade by this name, the best of which is produced in the province of Yemen. It is a variety of " Arabica," with rather small berries, and is of a superior flavour and aroma.