The tea plant undoubtedly reaches its highest perfection as a member of the vegetable kingdom, in India and Ceylon, in a climate of extreme heat and extreme rainfall and moisture, and in a very rich soil; and the remark is often heard from Indian planters that "tea and malarious fevers flourish together."
Experience has shown however that the tea plant possesses a wonderful power of accomodation to adverse conditions. In China and in the United states, it has been taught to put up with a comparatively sterile soil, dry mountain air, at heights in China reaching 6,000 feet above sea level, and occasional temperatures as low as 12 to 10 degrees Fahr., in the midst of recurrent ice and snow.
The story of tea in j.a.pan alone calls for more s.p.a.ce than this entire book could furnish, and there is an ample field for a treatise upon the cultivation, preparation, and social importance of tea in that strikingly interesting land. Nearly one half of the tea consumed in the United states comes from j.a.pan, our imports of j.a.pan tea being about 44,000 pounds during last year.
Although tea has been grown in that country for more than siz centuries only about forty years.
Tea in j.a.pan is largely grown upon hill-slopes and in small plantations or gardens, the latter term being peculiarly appropriate to their neat, symmetrical and picturesque appearance. The character of the soil is noticeably connected with the quality of the tea. From the putting forth of new leaves in the Spring-time until the advent of its white fragrant blossoms in the Autumn, the tea plant is an object of admiration and affection with the susceptible, nature-loving j.a.panese.
We are indebted to an English gentleman and tea merchant who has resided in j.a.pan for 30 years, for many interesting facts connected with our subject.
He tells us that while the princ.i.p.al crop of teas for export is produced on plantations of comparatively recent establishment, there are tea gardens in the interior of j.a.pan which have been cultivated for 500 years; and that tea is still gathered from bushes which spring from roots which were planted 100 to 300 years ago. These ancient plants yield a tea in limited quant.i.ties which is elaborately and expensively prepared for the n.o.bility and wealthy j.a.panese, and commands prices running up as high as ten dollars a pound. Some of the choice tea which comes to this country is picked from plantations which have been in existence for 300 years, and is sold under the names of "challenge,"
"Violet," and "j.a.ponica" teas.
These facts are in striking contrast with the limited life of Chinese tea plants, as stated by Mr. Fortune.
j.a.pan teas do not fall into either of the three cla.s.ses into which Chinese and Indian teas have been divided. They have been styled green teas by the trade, but that appelation grew out of their customary color, and their mild odor and taste; while j.a.pan Black teas are now produced from the same leaf. j.a.pan teas are favorites with many persons who do not relish the herby taste of other Black teas, and with whom Chinese Green teas disagree.
CHAPTER VI.
Tea Manufacture.
The tedious, long-drawn-out details of tea manufacture, of the repeated, meaningless, tossing back and forth and Chinese juggling with the abused tea leaves, are but too familiar to students of the subject: and too disappointing also, when we are moved to ask--Why all this manipulation? What is the nature of the chemical changes which take place?
So far as we can ascertain by diligent inquiry and reading, no competent authority has answered these questions satisfactorily.
We have been deluged with generalities and opinions which contradict themselves, but when we search for a categorical answer to a simple question, experts hide under a shower of meaningless phrases. We, alas, are not an expert, nor a chemist, but just a simple enquirer in search of knowledge expressed in plain English. Therefore be patient dear reader with our endeavors to represent or interpret existing conditions of expert knowledge of tea manufacture at this time. Peradventure a feeble ray of light may illuminate the darkness of the subject.
Corrections and additions will be welcomed in our future editions and credit given to their authors.
Teas may conveniently be divided into the three cla.s.ses which have so long been recognized by the American tea trade, namely:
Green teas, the first remove from the green leaf.
Oolongs, delicate Black teas, having properties further developed than those of Green teas.
Souchongs, and Congous, both of which have been called "English Breakfast" teas by Americans, because the former teas were the customary breakfast beverages of the English people before the advent of Indian teas.
In these latter teas, fermentation and firing are prolonged beyond the treatment of Oolongs. The smoky flavor sometimes apparent is owing to careless and extreme firing.
In making Green tea, the object seems to be to expel the watery juices of the leaf and to cure or dry it with the least delay.
Hence, the leaves are not exposed to the sun, but are first dried in the air for a short time. They are next exposed to artificial heat, which renders them flaccid and pliable, and prepares them for the third operation of rolling, which twists the yielding leaf as seen in manufactured tea, rolls it up into b.a.l.l.s, and squeezes out a considerable portion of its watery juices. It is a singular fact that in the Chinese methods, they endeavor to get rid of the exuding juices, while in the Indian treatment, according to Mr. crole, the manufacturing expert, effort is made to preserve the sappy juice, and it is continually taken up again by the b.a.l.l.s of leaves. The b.a.l.l.s are now broken apart, and the scattered leaves are submitted to the final drying process by fire, which finishes Green tea. In this case, it is plainly the heating treatment which develops the faint flavor and odor of Green tea, for no fermentation is allowed to begin, unless indeed brief and un.o.bserved action takes place within the compressed b.a.l.l.s.
In making an Oolong Black tea, which occupies an intermediate position between Green tea and Black Souchongs and Congous, the leaves are first exposed to the action of the air for a considerable time, and in many cases, to the sun also. An incipient fermentation may take place, although this is denied by some. There is certainly a chemical change beyond the brief preliminary drying of Green tea. During this period the leaves (in China) are stirred and tossed by the hands. The effect, if not the object, is to expose greater surfaces to the air, and to increase oxidation. It is during this operation that the leaves first begin to manifest characteristics of manufactured tea, in the way of a fragrant tea odor which the green leaf did not possess. The development of sweet odors in new hay, quite different from those of green gra.s.s, and also the artificial development of flavor in tobacco leaves, may be recalled in this connection. This prolonged exposure to the air is termed "withering," and the leaves become soft and flaccid, as they do in the first artificial heating for Green tea. In withering, the leaves lose about one quarter of their weight in moisture. The leaves must not be bruised before the termination of this treatment, or injurious chemical changes will begin.
The second operation with Black tea is the same rolling into b.a.l.l.s, twisting and squeezing, as in Green tea. Mr. Crole says that the sap of the leaf thus liberated from its cells "is spread all over the surface of the rolled leaf, where it is in a very favorable position for the oxygen of the atmosphere to act upon it during the next stage of manufacture, namely, fermentation." Fermentation, he regards as an oxidation process mainly.
For the "fermentation" stage, if that controverted term correctly designates the process, the rolls are either left undisturbed to heat, or, as in Indian methods, the rolls are broken up, and the leaves distributed in drawers, with free access of air. In either case, a spontaneous heating follows, and chemical action is indicated by a change of color which reddens and darkens the leaf, and by the evolution of further pleasant "tea" odors. Some of the tannin is said to be converted into glucose.
Care must be taken, Mr. Crole says, to arrest fermentation at the proper stage by the first "firing," and this firing expels about half of the remaining moisture of the withered leaves, and probably develops an additional portion of those volatile oils which give fragrance and taste to manufactured tea; and which Mr.
Crole designates by the name of "theol." Too high or too long continued firing drives off these oils with the watery juices.
They are also wasted by exposure of manufactured tea to the atmosphere. Firing is sometimes divided into two or three stages.
In the above summary we have described all essential treatment of tea leaves necessary to produce manufactured tea.
To procure the extreme type of Black teas, a Souchong or Congou, the fermentation or oxidation, and the "cooking" process, is simply carried further, and with higher roasting, some of the volatile oils and delicate flavors are expelled, or are changed into other flavors. Judging by diminished effects upon tea drinkers, some of the volatile theine is also lost.
Both in China and j.a.pan it is the custom to give large portions of the tea crop which are intended for export to foreign countries, only a preliminary drying or curing sufficient to preserve them temporarily. When they arrive at the shipping ports they are subjected to additional firing and thorough drying.
CHAPTER VII.
Chemistry and Physiological Aspects of Tea.
If the reader desires an example of imperfect and arrested knowledge in some of the common affairs of life, let him collate the statements of scientific experts concerning the physiological effects upon mankind, of tea. He will then admit that "in a mult.i.tude of counsellors there is confusion."
Without pretending to more than the rudiments of chemical or physiological science, we shall attempt to examine the nature of tea, and its effects upon the human system; taking as a basis for our remarks Professor Jas. F. Johnston"s Chemistry of Common Life, from which work more recent writers draw most of their inspiration.
Chemists find in manufacturing tea leaves three princ.i.p.al const.i.tuents to which all the physiological effects of tea are attributed. These are, (1) Theine, (2) Essential or Volatile Oils, (3) Tannin.
Theine is present in the green leaf of tea, and is apparently unchanged in the manufactured leaf and in the infusion or beverage. We regard it as the one essential and the most valuable element of all teas, physiologically considered. Strangely enough theine is the one important const.i.tuent which is entirely neglected by the tea-tester and the trader. In testing and grading teas for purchase and sale, their appearance, odor and taste, their color and body when "drawn," determine their pecuniary value, without relation to their percentage of theine, or its effects upon the tester.
Theine has been found in nature in but a few plants, as in tea, in coffee, (then termed caffein), in Mat"e (Paraguay or Brazilian tea), and in the Kola nut of Africa. A very similar principle, having a.n.a.logous properties, but containing more nitrogen, exists in cocoa, (theobroma).
Theine, when isolated by heat from the tea leaf or infusions, condenses in minute white needles or crystals, having no odor and but a faintly bitter taste. In manufactured tea leaves, theine const.i.tutes from one to five percent. of their weight. According to Professor Johnston, three or four grains per day of this substance may be taken without injury by most persons; or such quant.i.ty as would be contained in half and ounce of Chinese black tea. Indian (a.s.sam) tea and Ceylon tea, being stronger in theine, would suffice in lesser quant.i.ty.
Theine is soluble in about 100 parts of hat water. It vaporizes at 185 degrees C. or 365 degrees Fahr., hence it is not driven off by continued boiling of tea infusion.
W. Dittmar found by experiment that prolonged steeping of tea leaves up to ten minutes increased the proportion of theine in the infusion. His results are as follows:
STEEPED 5 MINUTES.
Average of 8 samples Chinese tea:
Theine, per cent infusion--2.58 Tannin--3.06
Average of 6 samples Ceylon tea:
Theine--3.15 Tannin--5.87
Average 12 samples of Indian tea:
Theine--3.63 Tannin--6.77
STEEPED 10 MINUTES.
Theine, per cent infusion--2.79--Increase about 10 per cent Tannin--3.78--Increase about 25 per cent
Average of 6 samples Ceylon tea:
Theine--3.29--Increase about 5 per cent Tannin--7.30-- Increase about 25 per cent