Mr. Liang Zhangju once praised the baking technique of rock Tea: “The Wuyi baking method is truly the best in the world.” Here, the baking method refers to traditional charcoal baking.
To this day, mid-to-high-end Wuyi rock teas are still largely processed using traditional ancient charcoal baking techniques. Among the baking techniques used for major tea varieties, there is indeed no other tea that surpasses the Wuyi rock tea from Fujian's Wuyi Mountains. The charcoal baking and processing technique for Dahongpao, a type of Wuyi rock tea, is unique to it and has been listed as one of China's first batch of national intangible cultural heritages.
The “Complement to Ben Cao Gang Mu” (Supplement to Compendium of Materia Medica) comments on Wuyi rock tea: “All teas are cold in nature; those with weak stomachs often experience stagnation after drinking them. Only Wuyi tea is warm and does not harm the stomach. It is suitable for those who have stopped Drinking Tea due to addiction.”
Charcoal baking, as its name suggests, involves continuously baking tea using the residual heat of high-quality charcoal. During charcoal baking, the temperature in the baking cage is approximately 120 degrees Celsius. Let's take a look at the baking process for Wuyi rock tea:
Fire Making
Baking
Fire making involves lighting the wood charcoal by breaking it into appropriate sizes so that the charcoal can be evenly and densely placed on the baking rack. When lighting the fire, an open flame is used to ignite the surface of the charcoal completely.
Ash Spreading
Placing on the Baking Rack
The tea leaves are loaded into the baking cage until it is about eight-tenths full. The temperature in the baking cage is controlled between 60-120°C, and the baking time generally ranges from 2 to 10 hours.
Turning the Tea
Based on different temperatures, the rock tea is turned at appropriate times. To turn the tea, the baking cage is moved away to prevent tea crumbs from falling into the charcoal fire, which could produce smoke and odors that would affect the quality of the tea in the cage.
Turning the tea is divided into hard turning and soft turning. Hard turning directly swaps the top layer of tea with the bottom layer within the cage to ensure even heating. Soft turning involves Pouring the tea from the cage into a basket, stirring it evenly, and then returning it to the cage before continuing the baking.
The turning process typically combines both hard and soft turning, resulting in excellent quality of the rock tea.
Tasting
After multiple turnings, 8 grams of tea is weighed each time, brewed in a lidded bowl, and evaluated to confirm whether the desired level of firing has been achieved. Experienced tea bakers can judge the level of firing through their sense of smell or by timing the baking duration at certain charcoal temperatures.
Removing from the Baking Rack
Once the tea meets the required standards, the baking cage is removed from the baking rack, and the tea is spread out to cool down. Once the temperature approaches room temperature, it can be bagged and sealed.
A good cup of tea requires going through the process from fire making to removing from the baking rack, with every step being crucial. Differences in temperature and time have a significant impact on the tea, determining its aroma, taste, and degree of firing.
The Effects of Charcoal Baking
1. Provides thermal energy, increasing the activity of the inner contents of the rock tea and accelerating the oxidation-reduction reactions of these substances.
2. Provides carbon elements, ensuring that catechins, Caffeine, and other substances do not compete for carbon elements from the sugars in the tea during oxidation, reducing the consumption of polysaccharides and other substances.
3. Promotes the formation of new complexes by amino acids, polyphenols, theaflavins, and caffeine, making the tea broth richer and more refreshing, thus reducing the bitterness of catechins and caffeine.
4. Continues the drying process of the tea leaves, controlling their moisture content below 5%. When the moisture content in the tea is between 3-5%, the water acts as a barrier against oxygen. Any level above or below this range can only promote oxidation. This is also one of the reasons why properly fired rock tea can be stored at room temperature for long periods.
In summary, the mutual achievement of traditional charcoal baking techniques and Wuyi rock tea is inseparable. After undergoing charcoal baking, Wuyi rock tea maximizes its “rock rhyme.” In terms of aroma, it tends towards a mature fragrance, with stable aromas and a special charcoal-roasted scent that lingers in the cup for a long time and is often accompanied by a milky fragrance. The dry tea has a more glossy appearance, and some exhibit a noticeable “frosting.” The flavor is rich, smooth, and chewy, with a higher purity of the broth, clearer and brighter color, and greater durability when steeped.