You may have heard of (or tasted) Pu-erh tea from China. This is one of the few teas that is deliberately aged. The tea leaves are specially processed and pressed into various shapes before the tea is stored away for several years. It is supposed to improve with time, but many people think that Pu-erh tea tastes like dirt.
There are also aged teas from Taiwan, but they are quite different from Pu-erh.
Aged Taiwan tea begins life as oolong tea. The processing is basically the same as oolong that is meant to be sold fresh.
If a tea is meant to be aged, however, it should have certain characteristics. The first is that it must be a high-mountain tea. Tea grown at high elevations has thicker leaves than low-altitude tea, and this give the tea a "density" that is necessary for aging. The tea should also be organically grown, free from pesticides or chemical fertilizers that will spoil the taste of the tea as it ages.
The tea leaves have to be picked at just the right time when they are neither too old nor too tender. A comparison is made with fresh fruit that is shipped to market - if it is too ripe it will spoil before delivery, if it is not ripe enough it will have less market value. The same with tea - the leaves must have the proper level of acidity to mature well.
A tea that is meant to be aged is ball-rolled just the same as "fresh" Taiwan oolongs. The main difference in processing is that the aged teas will be roasted slightly longer than non-aged teas to remove excess moisture. This is a delicate procedure - tea that is roasted too long will have a burnt flavor.
After it has been roasted the tea is stored away in a cool, dry location. It is important that the tea remains in the same place during the aging process. If the tea is moved the flavor will be affected.
The tea is aged in large earthenware pots. These pots have tightly fitting lids, but they are not sealed. The tea needs to "breathe" in order to age properly. It is still considered to be "alive" during the aging process, and placing it in a sealed container will not allow it to mature.
The tea is examined every 2 or 3 years, and if the tea master decides, it will be re-roasted to remove excess moisture and to retain the flavor of the tea.
After the tea has aged for 3 years it will have lost it's "fresh" flavor and begins the process of acquiring a mellowness that is characteristic of aged tea. From 5 to 10 years the color of the leaves turns from green to brown and the tea liquor takes on a reddish hue. After 15 years the tea is mature, although it will continue to improve with further aging.
The quality of "maturity" is often used to describe aged tea. Fresh tea, like youth, has vigor. Youth is also characterized by a lack of vision and an inability to persevere. So it is with fresh tea - wonderful fresh flavors but inconsistent from batch to batch.
Old age has a mellow character with an underlying vitality that has been acquired by years of experience. So it is with aged tea - a smooth, mellow beverage that provides a comforting stability, and invites a meditative frame of mind as we think of years past.