What is Pu-erh Tea aka 'Dark Tea'?
Most tea is produced by withering, rolling and drying the tea leaves (with black tea being allowed to fully oxidize). The herbal teas we are familiar with are mostly dried botanicals. Pu-erh (pronounced Pu-AR) tea is different in that it undergoes a fermentation period. Some use the term fermentation interchangably with oxidation, but they are both completely different processes.
All Pu-erh tea is fermented, and thus undergo a microbiotic process similar to other types of fermented food (saurkraut, sour dough, yoghurt). Originally the tea was pressed into cakes and allowed to age - SLOWLY. This is known as RAW Pu-erh. But later on, as demand in China increased, tea masters found they could accelerate the fermentation by piling heaps of tea on the ground an controlling the moisture as a way to speed up the process. Think of lawn clippings, and how they get hot in a pile. Same principle.
The term ‘Dark Tea’ doesn't apply to teas that are black or just dark colored. To be considered ‘Dark Tea’ the tea must be fermented. Besides Pu-erh, there are a few other ‘brick tea’ that are fermented, although these aren't widely available.
Since ripe puerh oxidizes, it looks like a black tea. Raw Pu-erh can take on the appearance of green or white tea - i.e. no oxidation. Both teas can be found in cake form, large cakes, or little cakes. But it's also common for tea makers to break up the cakes into loose form for easy serving or blending.
Unlike other teas, Pu-erh if stored properly can improve in quality over time.
Where does Pu-erh tea come from?
Named for the county of Pu-erh in the Yunnan province in china, Pu-erh is created by taking unoxidized green teas and storing/aging them. Over time the tea leaves ferment, giving them a distinct taste from their green tea counterparts. The process can take upwards of 10 years, with older teas being more prized (much like wines). This became a problem however, when in the 1970’s there was an increased demand for Pu-erh in Hong Kong. Without the ability to meet this demand a new method was devised to rapidly age green tea into Pu-erh.
What is the difference between raw and ripe Pu-erh?
There are two major types of Pu-erh tea: "Raw Pu-erh" and "Ripe Pu-erh". These two Pu-erh types are distinguished by their respective fermentation processes. Both types of Pu-erh are made from the same raw materials (mao cha) - freshly harvested tea leaves that have been wilted, either fried manually or tumbled through a heated rotating cylinder, kneaded and sun dried in open air. The term "Raw Pu-erh" refers to loose leaves, tea cakes or bricks made from raw materials without additional processing. Raw Pu-erh can be consumed immediately to enjoy its fresh, floral or fruity flavors, or it can be left to age in a natural environment to achieve a mellower, smoother and more complex flavor. Naturally aged Raw Pu-erh teas, particularly those made from premium raw materials, are the most sought-after by tea connoisseurs.
"Ripe Pu-erh" offers an alternative to having to wait ten to thirty years for the Raw Pu-erh to mature and achieve the aged flavor that is popular among many Chinese. In the 1970's, the industry developed a method to accelerate the aging process by "cooking" Pu-erh tea. This "cooking" process, called "wo dui", involves incubating the tea in a moisture-rich environment where microbial activity causes the temperature to rise, drastically intensifying the fermentation process. This process typically takes a few months to complete.
Here is a comparison between a raw and a ripe Pu-erh:
Time required to achieve full fermentation:
Raw: 20-30 years.
Ripe: A few months.
Taste differences:
Raw: Young raw-Pu-erh shares similar characteristics as green tea. As the tea ages, it becomes more complex and is famous for its stronger mouth sensation and long-lasting aftertaste.
Ripe: Earthy and mellow. Aged ripe Pu-erh becomes smoother and the earthy flavor transforms into sweet plum flavor.
Color of the brew:
Raw: Golden yellow to burnt orange, depending on the age of the tea
Ripe: Dark chestnut Appearance of the leaves: Raw: The brewed leaves of raw Pu-erh are more intact, plump and soft. Ripe: The brewed leaves of ripe Pu-erh are generally broken, black in color and no longer soft.
Aged Raw Pu-erh is not easy to find, and much of it doesn't make it to export. However, there are many good quality ripe aged Pu-erh options that compete in this market.
What are Pu-erh cakes?
Because Pu-erh goes through a process of fermentation which involves moisture, the leaves can be pressed into various shapes. Once pressed, they can be stored and aged. Pu-erh is unique among teas in that it can be stored for many years and improve with age, assuming kept under the right conditions.
The "cakes" as they are called come in various shapes and sizes, from large discs that you break off into small servings, to mini-cakes or "birds nests" that make one pot. Very often Pu-erh is broken up in advance into a loose form that is easy to serve or blend with other teas
Health benefits of Pu-erh
Last but not least, Pu-erh has it's own distinct health benefits. While it is a fermented product, it is not a "live" product when it reaches your teacup. However Pu-erh is known to have beneficial health properties when it comes to digestion and circulation. Many have used it to aid in weight loss and reduce cholesterol.
Additionally, new research shows that ‘Dark Tea’ appears to help control blood sugar levels and stave off disease onset and progression of diabetes.
What Pu-erh to try first?
If you are new to Pu-erh, it probably best to start out with a flavored variety first. The earthy or 'elemental' flavor profile of Pu-erh may require repeated tasting to get used to. Pu-erh can be resteeped multiple times. Most pure, unflavored Pu-erh should be briefly rinsed with hot water before steeping. Doing this can remove potential chalky flavor from the first infusion.
While most Pu-erh is of the black variety, you can also find some Green and White versions will have more nuanced and less pronounced earthy notes.
Another notes, the longer the tea ages, the more ‘mellow’ it gets. Aged Pu-erh, especially certain types can command very high prices by enthusiasts.
