We have here to consider the sources of the three leading dietetic beverages. They are very unlike in general appearance, but all possess the same vegetable principle, called an alkaloid,[1] though known under different names. Thus modern chemistry has proved the identity of the theine of the tea, the caffeine[2] of the coffee and the theo-bromine[3] of the chocolate. This same vegetable alkaloid, remarkable for its large per cent. of nitrogen, is found in small quantities in a few other plants, most of which have been used to some extent for the making of an exhilarating drink. It answers our purpose best to treat each of our three subjects under its respective head.
Tea (Thea viridis[4]).—The tea of commerce is the prepared leaves of a shrub belonging to the order Camelliaceæ[5] represented in the United States by loblolly bay[6] and Stuartia.[7] Perhaps the most familiar near relative of the tea plant is the camellia of our green houses and window gardens. The wild tea shrub grows from twenty to thirty feet high, and is found native in China and Japan. When under cultivation the shrub is pruned so as to not exceed six feet in height. The flowers are large, white and fragrant; they are produced in clusters in the axils of the simple, oblong, evergreen, serrate leaves. China and Japan are among the leading tea-growing countries, its cultivation being chiefly confined between twenty-five and thirty-five north latitude. Tea was in general use in China in the ninth century, but it was not until the seventeenth century that it was introduced into Europe. About the middle of this century the East India Company imported tea into England, since which time it has become the regular beverage of many millions of people in all parts of the world. The importations of tea into the United States for the year ending June 30th, 1884, were 67,665,910 pounds. It will be seen that this gives somewhere near a pound and a quarter of tea for each man, woman and child in this country. Most of our China tea trade is carried on with Shanghai, Foo Chow and Amoy.
In China the tea shrub is grown chiefly on the southern slopes of hills in poor, well watered soil, to which manure is applied. The seeds are dropped in holes at regular intervals, and during the third year the first crop is obtained. In from seven to ten years the shrubs are cut down and shoots spring up from the stumps, which continue to yield crops of leaves. A single plant produces on an average between three hundred and three hundred and fifty pounds of dried leaves. The leaves are picked three times a year, in April, May, and June or July. The young, tender leaves of the first gathering make the best tea, and this is very largely consumed in its native country. The older leaves of the second and third pickings make a poorer quality of tea which abounds in tannin,[8] and contains but a small per cent. of the best elements of superior tea. It was long supposed that black and green sorts of tea were made from distinct varieties, or even species of plants; in fact, there has been a great deal of mystery surrounding the culture and preparation of tea until within the past score of years. Authorities now state that there is only one species of plant yielding tea leaves, and from this all sorts are made. The differences are natural, being some of them due to climate and conditions of soil, etc., while others are the result of the manipulation of the leaves after they are gathered. Black and green tea may come from the same shrub, or even the same branch of a plant. The leaves forming black tea undergo a fermentation before they are dried, while those designed for green tea are at once submitted to a high heat in iron pans, and not copper pans, as generally supposed. After the leaves for black tea have been gathered they are placed in heaps, when they become flaccid and turn dark from incipient fermentation. The leaves are then rolled between the thumb and fingers or upon bamboo tables until the desired twist is obtained. They next pass to a drying room and are heated in an iron pan; again twisted, and afterward dried over a slow fire. The principal difference between the preparation of black and green tea is that in the latter the freshly gathered leaves go at once into the heated pans. The repeated twisting and heating is nearly the same with both classes. The green teas are sometimes artificially colored by using turmeric[9] with gypsum or Prussian blue. A flavor is frequently given to the tea by adding aromatic flowers, as those of the pekoe and caper.[10] Among the leading varieties of black tea are: Bohea, a small leaf, crisp and strong odor, with brackish taste; two sorts of Congous—the large leaf with fine flavor, and the small leaf with a burnt smell. The Souchong is the much prized “English Breakfast,” made from leaves of three-year-old trees. Only a small part of the so-called Souchong is genuine. Pekoe is made from the tenderest leaves gathered from three-year-old plants while in bloom. Oolongs are common kinds of black teas, much used for mixing with other sorts. Of the green teas the Gunpowder is round, like shot, with green color and fragrant taste. The Imperial is more loosely rolled than the Gunpowder. Young Hyson is in loose rolls, which easily crumble to the touch; it gives a light green infusion. Old Hyson is the older leaves in the picking for Young Hyson. Twankay consists of mixed and broken leaves, and is of inferior quality. Japan teas are both colored and uncolored, and come from Japan; they are very largely consumed in this country.
The chemical composition of a fair sample of tea is; Theine, 1. to 3. per cent.; caseine,[11] 15.; gum, 18.; sugar, .3; tannin, 26.; aromatic oil, .75; fat, 4.; vegetable fiber, 20.; mineral substances, 5.; and water, 5. per cent.
The tannin is an astringent, while the theine acts as a gentle excitant upon the nervous system. This is probably enhanced by the warmth of the infusion. The best authorities agree that tea is a valuable article of diet for healthy, grown people. It however is not suitable for children until growth is completed. Adults with irritable constitutions may be injured by tea-drinking. Tea is the solace of old age. Cibber[12] wrote: “Tea! thou soft, thou sober, sage and venerable liquid … thou female tongue-running, smile-smoothing, heart-opening, wink-tippling cordial, to whose glorious insipidity I owe the happiest moments of my life, let me fall prostrate.” Waller[13] truthfully says:
“Tea doth our fancy aid,
Repress those vapors which the head invade
And keep the palace of the soul.”
Tea is extensively adulterated in many ways. In China exhausted tea leaves and foliage of other trees are employed by millions of pounds each year. Willow leaves are among the principal ones used for mixing with tea. A British consul once related that at Shanghai there were at one time 53,000 pounds of willow leaves in preparation to be sold as tea. Mineral matters are used to color or “face” the tea. “The common test,” states Mr. Felker, in his work “What the Grocers Sell Us,” “is by infusion; this is poured off the leaves and examined for color, taste, and odor, all of which are characteristic.… Impurities like sand, iron filings and dirt may be seen among the leaves or at the bottom of the cups. The leaves, too, betray by their coarseness and botanical character, the nature and quality of the tea, for although the leaves of the genuine tea differ much in form and size, yet their venation and general structure are very distinctive.… ‘Lie tea,’ used to adulterate Gunpowder tea, consists of tea dust mixed with mineral substances, starch and gum, and then formed into little masses resembling tea.” Large tea houses employ professional tea tasters who make steepings and judge upon the flavor, purity, etc.
Coffee.—The coffee of commerce is the seed of a shrub, Coffea Arabica,[14] belonging to the order Rubiaceæ,[15] which is represented in the United States by the charming little “bluets” of our pastures in spring. The cape jessamine and bouvardias[16] of the green house are near relatives of the coffee plant. The name coffee is probably derived from the Arabic word Kahwah, although some authorities contend that it is traced to Caffa, a province of Abyssinia, where the coffee plant flourishes in the wild state. The coffee shrub is an evergreen, growing to the height of twenty feet, with long, smooth, shining leaves. The pure white flowers are produced in clusters in the axils of the leaves and followed by fleshy berries which, when ripe, resemble small, dark red cherries. Each berry usually contains two seeds embedded in the yellowish pulp. These seeds, when separated from the pulp and papery covering, form the raw coffee of the stores. Each seed—improperly called a berry—is somewhat hemispherical, with a groove running through the middle of the flat side. Sometimes one seed is abortive in the berry, and the other becomes round, as in the Wynaad coffee from India, sometimes called “male berry” coffee.