A customer emailed in with some great questions about Wu Long processing.
Christopher: I was watching your travel videos and I had a question about the wu long making process. I noticed that for Phoenix and Yan Cha they shake the leaves on a big tray, but for Tie Guan Yin they do not, is there a reason for this?
Shunan: Thank you for asking a very observant question! While Tie Guan Yin does go through a lighter fermentation process in comparison to the other Wu Longs, it still gets shaken.
What makes Wu Long so aromatic is that the leaves go through a process where they are physically disturbed to regulate the water fed from stems to the leaves for enzyme activities.
This can be done in a few different ways; both the hand shaken on bamboo trays or rocking a large, hanging, bamboo bowl are considered more traditional and hand-made, but more labor intensive. Nowadays, they are only reserved for the best batches, even in the true origin location where the teas are much more prized than the surrounding and plantation teas. The most common method we see nowadays is to tumble the teas with a bamboo or steel barrel (bamboo is better). Some are powered by electricity but older versions are rolled by hand, which is considered better. All three methods are trying to do the same thing but using different tools.
Now back to your question about why Tie Guan Yin doesn't get shaken - it does, but with a tumbling machine. The sad truth is that Tie Guan Yin is now on a decline and many tea makers now do not deem the tea to be worthy of such more careful and labor intensive process. This happens with a lot of commercial teas and with teas of increasing popularity that need to utilize machines to meet demand, thus causing the eventual hype and decline. However, the best teas, not just Wu Long, are still being handmade, if there's enough incentives for these heritage farmers to continue do so (which on a large scale is not happening right now, most people cannot tell the difference). Btw, one of our past videos of Tie Guan Yin shows the hand shaking process of a small batch we commissioned.
C: I was also wondering about baking temperatures. I know that the kill green step on green teas is pretty high, how does this compare to baking. Also is baking the same across the board? Is the green tea baking the same as phoenix wu long and the same as red tea baking?
S: You ask all the great questions! There are generally three types of "bakings" in Chinese tea making, not counting killing the green, which is not really baking.
- Bake to dry is usually called Hong Gan, such as in the case of Mao Feng, or making Wu Long rough teas, or any teas that was not dried either with wok or sun. For Hong Gan, the temperature is medium high, usually below 120c with the tea's temperature around 80 - 85c, and gradually dropping over time.
- Bake to give flavor, usually called Bei Huo. There are two ways to roast teas in China, one is usually called La Huo or Zhuang Huo, which is a flash roasting method that is often seen in An Hui teas. This is a very labor intensive method and has to be done with great vigilance as the temperature is very high, basically open charcoal fire (no flame rising tough) and the tea can be burned in just a second. Gua Pian and Huang Ya both adopt such a method. A second method is often referred to Dun, means stewing in Chinese where the tea is "stewed" over low temperature for long period of time. The method is mostly used in Wu Longs using charcoal ash in a built in stone pit, baked at under 75c (tea temp) and for 6 - 12 hours at a time, with some teas baked two to three times.
- Bake to enhance aroma or to get rid of moisture or other flaws in prior steps of tea making, called Ti Xiang. This is a necessary step to make great red tea for aroma but often used for other teas for minor adjustments of flavors. The temperature needs to be adjusted at intervals from 110c to 85c to carefully and effectively drive out the last bits of moisture in tea, while getting rid of any impurities WITHOUT altering the taste profile of tea. Some of the very chocolaty red teas are usually messed up at this step.