## Title
Wuyi Rock Tea Charcoal Baking Technique

## Abstract
The charcoal baking process of Wuyi Rock Tea has a long history and is highly skilled. Among these processes, da bei (preparation of the charcoal fire) is an indispensable step in traditional Wuyi Rock Tea charcoal baking. It requires high technical proficiency and is closely related to the quality of the baked tea. This article discusses the significance of da bei in fully realizing the unique qualities of Wuyi Rock Tea. It covers the concept, purpose, tools, preparatory work, and technical details of da bei, providing insights into its nuances. This serves as a reference for gaining a deeper understanding of the distinctive features of Wuyi Rock Tea production techniques as a national intangible cultural heritage.

## Keywords
Wuyi Rock Tea; da bei; charcoal baking; tea-making technique

The unique traditional charcoal baking technique of Wuyi Rock Tea is an intangible cultural heritage. The baking process of Wuyi Rock Tea is very meticulous, with mid-to-high-grade Wuyi Rock Teas typically using traditional charcoal baking technology, which is the most elaborate among all major Chinese teas. As early as the Qing dynasty, Liang Zhangju commented, “Wuyi's baking method is truly the best in the world.” To bake good tea, one must first prepare the charcoal fire well. Da bei is an essential part of the traditional Wuyi Rock Tea charcoal baking process and comes with specific requirements and techniques. If not properly executed, it can affect the quality of the baked tea.

### 1. Purpose of Da Bei
Before the initial baking of Wuyi Rock Tea during processing, one must prepare the charcoal fire to provide the optimal heat source for baking and ensure stable temperatures within the baking cage. The process of preparing the charcoal fire is commonly referred to as “da bei.” The goal of da bei is to provide a stable and appropriate baking temperature for charcoal baking, meeting the requirements of slow baking over low heat for Wuyi Rock Tea.

### 2. Preparation of the Baking Room and Da Bei Tools
#### 2.1 Baking Room (Baking Chamber) and Baking Pit
The orientation of the Wuyi Rock Tea baking room should ideally be north-south, with windows and doors on the north and south walls to facilitate ventilation and natural lighting. Baking pits are arranged around the interior ground level. In older tea factories, a suspension rack was typically set up beneath the baking room, with mud walls for insulation. A tea delivery window was installed in the partition wall between the baking room and the tea rolling room. Above the baking room was often a drying loft, where the rising heat could be used to warm the tea leaves during withering. Modern Wuyi Rock Tea factories have baking chambers made of brick and concrete, with a large exhaust skylight at the top to promote upward airflow, thus driving the heat from the charcoal fires upwards through the tea leaves, facilitating even heat absorption.

Baking pits are generally arranged along the walls of the baking room, with their location determined by the size of the room. In older tea factories, the pits were typically built with a mixture of soil or yellow clay, with pits dug into the soil layer (Figure 1). Each pit is about 26 cm high and 77 cm wide, with a round surface diameter of 34 cm and a bottom diameter of 26 cm. The distance between pits is 40 cm. The outer edges of the pits are preferably lined with stones or bricks to prevent collapse. If digging pits is difficult, iron pots can also be used as substitutes. The number of pits required depends on the amount of tea being processed. For instance, if 500 kg of tea is processed daily, 20 pits would be needed, and the number of pits used each day varies according to the amount of tea leaves processed that day.

[Figure 1](https://oss.puercn.com/fit/800/800/we/0/chayou/entry_photos/000/969/542/0.png): Baking pits at the ancient tea factory site in Bachu Mountain (Photographed by Yang Jinyi)

In modern baking chambers, the pits are typically constructed using bricks and concrete (Figure 2). Half-bricks are laid horizontally at the bottom, followed by vertical bricks forming the base, and then the round pits are built using bricks. The length of the base is determined by the size of the baking chamber, usually about 82 cm wide. The depth of the pits is 36 cm, with a surface diameter of 56 cm and a bottom diameter of 52 cm. The distance between pits is 28 cm. When pouring and smoothing the concrete mortar, a certain amount of salt is added to increase the strength of the pits and bases.

[Figure 2](https://oss.puercn.com/fit/800/800/we/0/chayou/entry_photos/000/969/543/1.png): Baking pits in the baking chamber

#### 2.2 Da Bei Tools
Da bei tools generally include a baking shovel, baking knife, charcoal scoop, ash scraper, ash sieve, hoe, four-pronged rake, shovel, dustpan, waste bin, broom, etc. (Figure 3).

[Figure 3](https://oss.puercn.com/fit/800/800/we/0/chayou/entry_photos/000/969/544/2.png): Da bei tools

– **Baking Shovel**: Made of iron, shaped like a spade, with a rectangular front end measuring 15 cm wide and 12 cm long, and an iron handle 38 cm long. It can be equipped with a long wooden handle for use while standing at a distance, to reach into the pit and break up the charcoal when starting the fire. One to two baking shovels can be configured per baking chamber.
– **Baking Knife**: Made of iron, shaped like a small knife, 10 cm wide and 20 cm long, with an iron handle 14 cm long and a short wooden handle. Used to tidy up the fire stack during ignition, preventing the charcoal stack from collapsing and ensuring even heat distribution. Two baking knives are configured per baking chamber.
– **Charcoal Scoop**: Made of iron, approximately 25 cm in diameter and 10 cm deep, with an 8 cm iron handle and a 40 cm wooden handle. Used to hold charcoal and ash.
– **Ash Scraper**: A small knife made of wood, similar in shape to the baking knife but slightly smaller and with a pointed tip. It measures 13 cm long and 10 cm wide at its widest point, with a short handle. Used to scrape off or cover the ashes on the fire stack to regulate the heat. Two ash scrapers are configured per baking chamber.
– **Ash Sieve**: Comes in flat round and curved round shapes, used to sift out impurities such as pebbles and small charcoal pieces mixed in with the ash.
– **Hoe**: A common long-handled farming tool, used to break apart charcoal, turn and rake the charcoal.
– **Four-pronged Rake**: An iron rake with a wooden handle. One side has a cylindrical sheath into which the wooden handle can be inserted, and the other side has four evenly spaced teeth. Used to turn and rake charcoal and charcoal heads.
– **Shovel, Broom, Dustpan, Waste Bin**: Common tools used together to shovel and collect charcoal, sweep away ash, and clean the floor of the baking chamber.

### 3. Preparations Before Da Bei
Before da bei, the baking pits need to be cleaned and the charcoal prepared. For newly ignited pits, any remaining ash and other debris must be cleared using a charcoal scoop, broom, etc. For continuous da bei, the residual ash in the pits is scraped clean, and the remaining embers are left as “fire starters” and covered with ash. If the ash scraped from the existing pits is used for covering, it must be sifted to remove impurities to avoid affecting the scraping of the ash with the ash scraper. This ensures a smooth and even surface of the charcoal fire without exposed flames. If conditions permit, burned rice husk ash or bracken ash can also be used for covering.

The charcoal used for charcoal-baked rock tea must be natural charcoal, preferably made from hard, high-density woods such as paper mulberry, beech, and yellow sandalwood. Nowadays, charcoal is often made from longan and lychee trees. First, break down any excessively long charcoal sticks into uniform small pieces to make them easier to place in the pits.

When igniting the charcoal, observe how quickly it burns and whether it smokes. If the charcoal is difficult to ignite or continues to smoke during burning, it can be judged that this batch of charcoal has a high moisture content or contains incompletely burned charcoal pieces. The charcoal needs to be dried or the charcoal pieces removed before use.

### 4. Methods of Da Bei
There are two methods of da bei: “open da bei” and “closed da bei.” Different da bei methods can also affect the quality of the baked tea. Generally, one da bei session can last for more than ten days of baking, depending on factors such as the size and depth of the pits