“Aging brings aroma” is the core value of Pu'er Tea, a consensus in the industry, and the primary reason for its rapid rise over the past decade. To unravel the mystery of Pu'er tea's “aging brings aroma,” various sectors have been conducting exploratory research and practical work. It is now generally agreed that there are three most important factors: raw material as the foundation; processing technique as the key; and storage as the guarantee.
For a long time, due to the craze for ancient tree teas, most people's focus was on raw materials and processing techniques. Compared to the past, I believe this represents significant progress in the industry. This progress has largely completed the two most critical steps, greatly enhancing the feasibility of Pu'er tea's “aging brings aroma.” What remains is the conversion through storage.
In recent years, more and more people have shifted their attention to the conversion through storage. If we look at other food sectors with similar “aging brings aroma” characteristics, such as cigars, whiskey, wine, and China's premium liquors, we find that these industries have established industry standards and systems for conversion through storage. Some companies have even developed their own higher corporate standards based on industry standards. In other words, they have already integrated conversion through storage into their product production processes.
In contrast, the current situation in our Pu'er tea industry is that manufacturers often sell raw and new teas directly to consumers, simultaneously transferring the responsibility for later conversion to intermediaries or consumers. As intermediaries and consumers, without adequate conditions for conversion through storage (both software and hardware), there may be significant risks. Therefore, we need to provide a set of scientific, systematic theories, logic, and methods for Pu'er tea enthusiasts.
It is against this background that we propose the concept of scientific storage. The purpose is merely to offer a starting point, hoping to promote the integration of conversion through storage into Pu'er tea production processes and facilitate the establishment of standards and norms for Pu'er tea storage conversion. Together, we aim to contribute to the sustainable development of the Pu'er tea industry.
Ripe tea, as a product of rapid fermentation, plays an important role in the promotion and popularization of Pu'er tea through quick sales and consumption. However, because of its different processing techniques, ripe tea is intended for quick consumption rather than classic collection. Therefore, the scientific storage we propose here primarily targets raw tea.
Definition of Scientific Storage
We propose the concept of scientific storage, which is not a specific device, location, or indicator. These things are the results of phased development and will change with ongoing research and development. It might be a methodological approach to “understanding the nature of Pu'er tea.”
If we define scientific storage, it is a storage system that adheres to the spirit of science and involves relevant research and empirical verification. At its core is the spirit of science and a scientific system. The core values of the scientific spirit are: authenticity, logic, empiricism, and innovation. Technically speaking, scientific storage is a system, and within this system, whether theory, technology, or hardware, each component is indispensable. Therefore, we believe that the scientific storage system includes: first, a theoretical system; second, an empirical system; third, a service system; fourth, an evaluation system.
Science is always evolving. Our current research on Pu'er tea is far from sufficient, but we believe that everyone can proceed based on the spirit of science. Only then will more consumers trust that Pu'er tea's “aging brings aroma” is scientific and promising. We hope that related scientific research on Pu'er tea storage conversion will establish theories, models, logic, methods, and databases as soon as possible.
Goals of Scientific Storage
First, realization of consumer value. Through conversion through storage, quality is significantly improved, and palatability is enhanced, thus promoting consumption.
Second, realization of production value. As part of the Pu'er tea production process, it should be operable, replicable, and predictable, providing guidance and assistance for the production and operation of Pu'er tea.
Third, realization of commercial value. Primarily safety and economy. Of course, the tea products subject to conversion through storage must possess basic characteristics such as quality, scarcity, and traceability.
In summary, the purpose of scientific storage is to utilize the scientific and economically viable production method of conversion through storage to achieve the maximum enhancement of the quality of tea products until “aging brings aroma.”
Premise of Scientific Storage
As mentioned earlier, the three elements of Pu'er tea's “aging brings aroma” are raw materials, processing techniques, and storage. In other words, if storage is considered the final link, discussing conversion through storage and “aging brings aroma” without considering the preceding raw materials and processing techniques would be futile.
What kind of raw materials and processing techniques can ensure that later conversion through storage achieves “aging brings aroma”? Certainly, high-quality raw materials and correct processing techniques are required. We will not delve into this topic here. However, we can solve this problem with the simplest, easiest, and fairest method: evidence. Regardless of any theoretical school, the final word is determined by facts and proven by evidence.
For a company, the best evidence is its products over the years. Since 2015, Gu Yun Liu Xiang has held a product tasting session in October every year to evaluate five-year-aged products. Starting in 2025, it holds annual tasting sessions in October for five-year and ten-year products. This activity aims to test whether our products truly achieve “aging brings aroma” and is also the best way to verify the accuracy and effectiveness of our theoretical system. The answer is affirmative.
Techniques of Scientific Storage
1. Biochemical principles of storage aging
Fundamentally, the conversion of Pu'er tea through storage is mainly a maturation (natural fermentation) process. This is similar to many other foods, such as cigars, liquor, and wine, where the basic principle is microbial Metabolism and slow oxidation reactions, among other complex processes. Unfortunately, up to this point, no clear and accurate theoretical model exists for the maturation process across various fields. Therefore, in practical applications, most rely on technical indicators controlled by experience. The actual situation of conversion through storage in the Pu'er tea industry is to create or control a reasonable environment based on past experience to regulate microbial activity and oxidation reactions, thereby achieving optimal improvement in the quality of Pu'er tea products.
2. Key factors in storage conversion
The key factors in the conversion of Pu'er tea through storage are temperature and humidity, which is a basic consensus. Different schools of thought and theories form different technical control indicators, resulting in different styles of tea products. For example, regional classifications include Guangdong storage, Hong Kong storage, Kunming storage, etc., and classifications by environmental dryness and humidity include dry storage, humid storage, etc. There is a diversity of views and vigorous debate, all driving the development of this craft technology.
We have identified some simple patterns through practice, which we share for your reference and critique!
High temperature and high humidity: Products convert rapidly, and flavor components decompose and dissipate particularly quickly;
High temperature and low humidity: Products tend to develop an acidic flavor;
Low temperature and high humidity: Products have a tendency to mold;
Low temperature and low humidity: Product conversion is slow, and substances are well-preserved.
3. Characteristics of different stages of conversion through storage of Pu'er tea