from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. caffeine when present in tea
from the GNU version of the Collaborative International Dictionary of English
- n. See caffeine. Called also theina.
from The Century Dictionary and Cyclopedia
- n. A bitter crystallizable volatile principle (C8H10N4O2) found in tea, coffee, and some other plants, tea yielding from 2 to 4 per cent.
Sorry, no etymologies found.
The leaves yield the same bitter principle called theine, which is found in the leaf of the Chinese tea-plant, the coffee berry, &c.
The Commercial Products of the Vegetable Kingdom Considered in Their Various Uses to Man and in Their Relation to the Arts and Manufactures; Forming a Practical Treatise & Handbook of Reference for the Colonist, Manufacturer, Merchant, and Consumer, on the Cultivation, Preparation for Shipment, and Commercial Value, &c. of the Various Substances Obtained From Trees and Plants, Entering into the Husbandry of Tropical and Sub-tropical Regions, &c.
The active principle of tea is called theine; that of coffee, caffeine, and of cocoa, theobromine.
The chemical principle of tea, namely theine, was subsequently tried and produced no effect.
Tea is often drunk at social events, especially early in the day to heighten alertness — it contains theophylline and bound caffeine (sometimes called "theine"), although there are also decaffeinated teas.
They were suffering, in fact, from "theine" poisoning.
It also exists in tea, formerly known as "theine" which is now known to be identical with caffeine; both are expressed by the formula
Personally, I have noted different effects from caffeine vs. theine (or even mateine), and though there is no scientific evidence for this (that I could find), it may be due to other compounds in the liquid.
Red tea is referring to rooibos tea – the sweet tasting South African bush, used as a superior, in my opinion substitute to black tea – less the theine.
The first of these is caffeine, which is almost identical in composition with, and practically the same as, the theine present in tea.
It was claimed for this special model that it extracted only the theine, and not the tannin from the tea.