These aged and fermented teas are revered throughout Asia for their unique taste and medicinal benefits. Pu-erh can be classified in two ways, depending on how it is processed.

The oldest method creates a Pu-erh that is called “Sheng” (raw). This traditional process involves compressing loose green tea into cakes. These cakes are slowly fermented over a very long period of time, usually from 10 to 50 years. When the cake is at least 30 years old, it is considered matured and given the label of “vintage.”

In the 1970s a faster method of processing Pu-erh was invented. This Pu-erh is called “Shou” (cooked or ripe). The process is the same as in the Sheng variety, but to speed us the aging process, the tea is exposed to rapid fermentation over 45–60 days, and then formed into blocks. before it is formed into bricks. This expedited fermentation is done by putting the tea in piles and kept moist and hot, to encourage beneficial yeasts and molds to grow. Once the fermentation is well underway, the tea is pressed into a variety of shapes. Ripe Pu-erh has more caffeine than Raw Pu-erh.