I ought, perhaps, to add that theinecollected as a waste product of coffee, and purified by myself, has cost me less than threepence per ounce troy.
Theine seems to act chiefly on the great sympathetic or ganglionic system of nerves, and but slightly on the brain.
As the result of much experience, I have obtained on an average, 75 grains of theine from the roasting of 1 lb.
Its active ingredient, Paraguaine, formerly supposed to be a distinct principle, has from further researches into its composition been discovered to be identical with theine and caffeine--the alkaloids of tea and coffee.
Theine is absolutely insoluble in a concentrated solution of the carbonate of potash, and thus we may precipitate it from its admixture with sugar, mucilage, and vegetable extract.
I will now relate the fact upon which the purification of theine depends, and when this is once clearly understood, the manufacture of theine from either tea or coffee becomes an extremely simple matter.
Dr Walter Blyth, commenting upon the above, says, the amount of theine is certainly understated.
Medical Times and Gazette' for 1871, directs attention to the value of theine as a therapeutic agent, as well as gives an easy method for its preparation.
Theine or caffeine is a feathery-looking substance which resembles the material of a silk-worm's cocoon.
There is more theine or caffeine in tea leaves than in coffee.
For statistics and theine percentages, see Appendix LVII.
The active principle is theobromine, a substance which resembles the alkaloids of coffee and tea, except that it contains more nitrogen than theine and caffeine.
In the proper preparation of Tea for use, therefore, the object should be to extract as little of the tannin as possible and as much of the theine and volatile oil as can be extracted without permitting the infusion to boil or overdraw.
It contains the same active principle, theine as tea and coffee, but not their volatile and empyreumatic oils.
The active principles of the leaves aretheine and a volatile oil, to which latter the flavor and odor are due.
Tea contains two harmful substances, theine and tannin,--from three to six per cent of the former and more than one fourth its weight of the latter.
Cocoa and chocolate contain substances similar to theine and equally harmful, though usually present in much less proportion than in tea.
Theine is a poison belonging to the same class of poisonous alkaloids, and is closely allied to cocaine.
Coffee contains caffein, a principle identical with theine and a modified form of tannin, though in less quantity than tea.
But the effects of tea are due to itstheine and tannin.
Theine is present in all kinds of tea, as well as in coffee and cocoa, but it has no flavor.
Dittmar found by experiment that prolonged steeping of tea leaves up to ten minutes increased the proportion of theine in the infusion.
Theine is present in the green leaf of tea, and is apparently unchanged in the manufactured leaf and in the infusion or beverage.
Strangely enough theine is the one important constituent which is entirely neglected by the tea-tester and the trader.
In manufactured tea leaves, theineconstitutes from one to five percent.
Theine is the one constant agency in the effects of tea.
Judging by diminished effects upon tea drinkers, some of the volatile theine is also lost.
Theine is soluble in about 100 parts of hat water.
The caffein or theine in tea is an alkaloid that has characteristic physiological properties.
The quantity of theine consumed in a cup of tea is about 4/5 of a grain, or 1/4 of a medicinal dose.
Its properties appear to be chiefly due to theine and caffeine.
It is also slightly stimulating, owing to the presence of an alkaloid theobromine which is closely similar in its properties to theine and caffeine, the active constituents of tea and coffee.
According to Professor Prescott, "the administration of theine in small portions, to animals or to man, quickens the circulation and effects some degree of mental exhilaration and wakefulness.
Medically speaking, thistheine has a totally distinctive action from the infusions of which it forms a part.
Individual medical investigators have, more than this, attempted, from time to time, to show that the action of theineis allied to that of quinine.
Professor Prescott makes this very interesting remark with regard to the chemistry of coffee and tea: "But the change of guanine into theine is easily accomplished.
In the following tea assay proper the estimation of theineis not included.
The processes suggested for this determination are rather unsatisfactory; and there appears, moreover, to exist no direct relation between the quality of tea and the proportion of theine contained.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "theine" in a variety of sentences. We hope that you will now be able to make sentences using this word.
