Dark Tea storage typically involves keeping the tea in a specific building, area, or container where, under certain temperature and humidity conditions, microbial, enzymatic, and oxidation processes cause changes to its internal components. This is a critical step in developing the distinctive qualities of dark tea.

This article summarizes the role of storage in enhancing the quality of dark tea, factors affecting storage, and storage models for dark tea. Using Liubao tea as an example, it analyzes the importance of professional storage and aging technology in the production and processing of Liubao tea, and looks forward to future research directions for professional storage technology for Liubao tea.

I. The Role of Storage in Enhancing Dark Tea Quality

Some freshly made dark teas have poor palatability, but after a period of storage and aging, their harshness diminishes, improving palatability. The taste becomes smoother with increased salivation and a stronger aftertaste. The tea's color becomes brighter and deeper, increasing consumer acceptance. Additionally, volatile compounds produced during fermentation are retained or transformed during storage and aging, enriching the aroma profile.

II. Factors Affecting Dark Tea Storage and Aging

For dark tea, a favorable storage environment not only reduces the time needed for aging but also helps improve its quality. Key factors affecting dark tea storage and aging include temperature and humidity, storage duration, storage location, and other special factors.

1. Temperature and Humidity Impact on Dark Tea Quality

Storing dark tea under suitable temperature and humidity conditions facilitates the transformation of its quality components. Under consistent conditions, higher moisture content generally leads to more intense chemical reactions. Studies show that storing in a humid environment (relative humidity 85%, temperature 25–40°C) has a more pronounced effect on the tea's components compared to dry storage (relative humidity 70%, temperature 18–30°C), accelerating the oxidation and degradation of polyphenols and reducing pigment content. Liubao tea benefits from two stages of aging (one “high humidity” at 80%–85% and one “low humidity” at 70%–75%), which enhances its aged aroma quality. Since tea has a tendency to absorb moisture, its moisture content is closely related to air humidity. If the storage environment is too dry, microbial activity decreases, slowing down or halting the transformation of chemical components in the tea, ultimately leading to a decline in quality.

2. Duration of Storage Impact on Dark Tea Quality

Long-term storage and aging help develop better flavor qualities or enhanced Health benefits in dark tea. For example, the longer Fu brick tea is stored, the better its anti-diarrheal effects become; the longer Kang brick tea is stored, the stronger its antioxidant capacity and ability to scavenge DPPH radicals. In terms of flavor quality components, extending the storage time allows some substances produced during fermentation to transform into new substances. As the storage and aging time of Liubao tea increases, the content of polyphenols and total sugars decreases while the content of theaflavins, thearubigins, and theabrownins increases. Relative contents of aroma components like α-farnesene, methyl salicylate, and benzyl acetate also increase significantly, improving the overall quality of Liubao tea.

3. Location Impact on Dark Tea Quality

The storage location significantly affects the sensory and chemical qualities of Liubao tea. When Liubao tea is stored in different locations such as Guilin and Wuzhou in Guangxi, or in underground cellars, warehouses, or alternating environments, differences in quality are observed.

4. Impact of Special Factors Such as Ultra-High Pressure, Irradiation, and Negative Oxygen Ions on Dark Tea Quality

Special factors like ultra-high pressure treatment, irradiation, and negative oxygen ions can also impact the quality and safety of dark tea. Appropriate ultra-high pressure treatment or storing the tea in an environment rich in negative oxygen ions can effectively enhance the quality of dark tea, especially when treated with high-voltage pulsed electric fields, which not only accelerates the aging process but also has good sterilization effects. These factors have significant impacts on the quality of Liubao tea, such as oxygen-enriched irradiation technology, which effectively increases the content of water-soluble extracts, soluble sugars, amino acids, tea polysaccharides, and thearubigins while decreasing the content of theaflavins, tea polyphenols, crude fiber, and moisture, thus rapidly and effectively improving the quality of Liubao tea.

III. Progress in Dark Tea Storage Models

Traditional dark tea storage models often rely on natural climate conditions, resulting in varied flavors due to different storage sites and conditions. They also suffer from low space utilization, difficulty in real-time monitoring and timely intervention of storage environments, and weak traceability information systems. Modern storage models impose stricter requirements on storage environments by controlling temperature, humidity, oxygen levels, and light, thereby regulating the transformation of internal components to achieve quality preservation and enhancement. For example, using wooden pallets for dry storage of Liubao tea not only moderates temperature fluctuations but also, through the pallets' own absorption and desorption functions, mitigates changes in indoor humidity, maintaining microbial activity to some extent and adsorbing tea aromas, achieving good aging effects.

However, modern storage models still have room for improvement. In the future, we can refine storage standards, establish an innovative storage model integrating “internet + big data + scientific aging + standard storage + artificial intelligence + finance + modern logistics,” and achieve the demonstration application of “professional storage + industrial integration development” for Liubao tea, promoting high-quality development of the Liubao tea industry.

If there are any copyright issues, please contact us for removal.