(c) Into 2 test tubes put 1 teaspoonful of each kind of beverage. To each tube, add 1/2 teaspoonful of ferrous sulphate solution and let the tubes stand. If a black substance appears in the tubes, tannin is present. Which kind of beverage,—black or green tea,—shows the greater quantity of tannin?
By fermentation, tannin is changed into a less soluble form, so the beverage made from black tea contains less tannin than that made from green tea. Hence, black tea is preferable. It is, however, slightly more stimulating than green tea. Good black tea is grayish black in color, not dead black. "English Breakfast" is a black tea. It consists of a mixture of several black teas. "Oolong" is black in appearance, but has the flavor of green tea. This is because it is only semi-fermented. Teas grown in various countries have different flavors.
Tea is sometimes adulterated by using the leaves of other plants or by adding large leaves and stems. It is said the finest brands of tea do not reach this country.
MAKING THE BEVERAGE.—Because tea contains tannic acid, an earthen, enamel, china, or silver teapot should be used; a tin teapot should never be used. (See Suggestions for Cooking Fruits.) The ingredient in tea that gives it its odor and flavor is a volatile substance. Hence tea leaves should be kept in closely covered jars or cans.
Boiling water draws out substances which give the beverage its flavor and stimulating properties, while water below the boiling point only partially draws out these substances. If, however, the leaves are boiled or are allowed to remain in water for more than five minutes, much tannin is drawn out in the water. Therefore, never boil tea, but pour boiling water over it and in five minutes strain out the tea leaves.
TEA (proportion for one cupful)
1/4 to 1 teaspoonful black tea leaves 1 cupful freshly boiled water
Heat the teapot by pouring boiling water into it. Pour out the water and add the tea leaves. Pour over them the freshly boiled water. Place the teapot in a warm place to steep, and in 5 minutes strain out the tea leaves.
Teapots provided with perforated cups or with tea-balls (see Figure 20) for holding the tea leaves are most convenient, as the cup containing the leaves may easily be removed or the tea-ball can be drawn above the surface of the liquid after steeping the tea for 5 minutes. Or two teapots may be used, the beverage being strained from one teapot into the other.
The quantity of tea to be used varies with the strength of tea desired. If the leaves are closely rolled, less tea is required than if they are loosely folded.