Tea blending and additives

Tea blending is the act of blending different teas (and sometimes other products) to produce a final product that differs in flavor from the original tea used. This occurs chiefly with black tea, which is blended to make most tea bags, but it can also occur with such teas as Pu-erh, where leaves are blended from different regions before being compressed. The most prominent type of tea blending is commercial tea blending, which is used to ensure consistency of a batch on a mass scale so that any variations between different batches and seasons of tea production do not affect the final product. Commercially, it is considered important that any batch of a particular blend must taste the same as the previous batch, so a consumer will not be able to detect a difference in flavor from one purchase to the next.
Another common practice is to scent tea leaves or blend tea leaves with herbs, fruits or spices, either for health purposes or to add interesting and more complex aromas and flavor notes. These kinds of teas are usually termed "scented tea" (especially when the tea leaves are only scented with certain aromas) or "flavored teas" (particularly when additives like flowers, oils, bits of fruit, flavorings, or other herbs are blended in with the tea leaves to be infused together). Another method of flavoring tea leaves is to smoke them in various ways, such as the pinewood smoking used for lapsang souchong.
Because tea takes on aromas with ease, there can be problems in the processing, transportation or storage of tea, but this property can also be consciously used to prepare flavored teas. Commercial flavored tea is often flavored in large blending drums with perfumes, flavorings, or essential oils. Although blending and scenting teas can add an additional dimension to tea, the process may also sometimes be used to cover and obscure the quality of sub-standard teas.
Teas blended with other additives were developed in ancient China. As far back as the Jin dynasty (266–420), ground up tea leaves were boiled with scallions, ginger, and orange peels as reported in the Guangya dictionary (c. 3rd century CE). During the Tang dynasty, tea was often blended with flowers. During the Song era (960 to 1279), the most expensive tea, called wax tea, was often covered with aromatic ointments, like Borneo camphor. In the Qing dynasty (1644–1912), the Manchus popularized scented teas, such as jasmine tea and teas scented with cloranthus, cassia, honeysuckle, and rose.
Although many teas are still scented or flavored directly with flowers, herbs, spices, or even smoke, teas with more specialized flavors are usually produced through the addition of flavorings or perfumes. This is particularly true for tea blends with pronounced fruit or flower aromas, which cannot be achieved with the original ingredients. Some firms such as Mariage Frères and Kusmi Tea have become quite famous for their perfumed teas. The most commonly used scents are jasmine, traditionally used to scent delicate white and green teas, and bergamot, which is used to scent Earl Grey tea. The teas described below are flavored directly with other materials.
A variety of flowers are used to flavor teas. Although flowers can be used to scent teas directly, most flower-scented teas on the market use perfumes and aromas to augment or replace the use of flowers. The most popular flower teas include the following: