Pu-erh tea: In Europe it is often only known to tea connoisseurs. In Asia, on the other hand, it is an absolute classic and one of the oldest varieties, if not the oldest. For a long time, pu-erh tea was even reserved only for nobility and occasionally also used as a means of payment. These days, it is considered the most expensive tea in the world. Why is pu-erh so valuable? For one, it is very rare, as the tea leaves come from old, wild tea trees found in southwest China. Secondly, the production process itself is true art. First, the green leaves are picked, dry-roasted in a wok and dried in the sun. Only then, the most important step begins: the maturation process. Microorganisms start growing over time due to a certain residual moisture, and these give pu-erh its characteristic, rich taste. We therefore generally distinguish between raw and aged pu-erh tea. With raw pu-erh tea, the tea leaves are exposed to high temperatures immediately after harvesting, which, technically speaking, makes this a green tea variety. So raw pu-erh is similarly light in colour and tastes just as fresh and grassy as green tea, whereas aged varieties are more like black tea, both in terms of the dark, reddish colour and the stronger taste. This taste develops during a maturation process that usually takes between 10 to 15 years, but can even take up to 50 years in particularly high-grade varieties. Similar to a fine wine, tea develops a more robust flavour profile over time. Pu-erh is therefore often referred to as a tea for advanced tea drinkers who are not intimidated by more complex aromas.