According to the classification of the six major tea types, Hunan Dark Tea, Yunnan Pu'er Tea, and Guangxi Liu Bao Tea all fall under the category of dark tea. But what are their differences?
In taxonomy, Pu'er belongs to the dark tea category, as both types are border teas, and most products are compressed teas that improve with age and have stronger medicinal properties over time. This is the basis for their classification. However, in terms of the principles of classification within the six major tea types, these two teas have significant differences in terms of their processing techniques and quality characteristics.
Traditional Pu'er tea is known as sun-dried Yunnan green tea, while dark tea has a characteristic process called “wet-piling” during initial processing. Wet-piling is dominated by microbial metabolism. Although microbes also participate in the sun-drying process of Pu'er tea, the environments (temperature and humidity conditions) are different. The former promotes the growth and reproduction of beneficial microorganisms, while the latter, after being exposed to sunlight, has a short duration and rapid water evaporation, which relatively inhibits microbial activity. Because of this, the quality characteristics of the raw teas are clearly different. Raw Pu'er tea has a strong grassy flavor and bitter taste, while dark tea has no grassy flavor but instead a spicy taste, with a milder and more harmonious taste and less bitterness and astringency. This is the difference between new Hunan Dark Tea and new raw Pu'er.
In later storage, although non-enzymatic oxidation and microbial action are the mechanisms for quality changes in both, the substances formed during raw tea processing have qualitative and quantitative differences (due to different mechanisms), resulting in different end-products. This is the key difference between aged Hunan Dark Tea and aged Yunnan raw cakes.
In 1973, Pu'er tea adopted a post-fermentation technique. Its fermentation occurs under high temperature and high humidity, significantly different from the wet-piling process in dark tea production. Firstly, there is a difference in reaction substrates: the substrate for Pu'er tea is based on the reaction products of sun-dried raw tea, while for dark tea, it is the semi-finished product after fixation. These cannot be equated. Secondly, the reaction conditions (temperature and humidity) differ, leading to a certain difference in the microbial populations.
According to Professor Wen Qiongying from Hunan Agricultural University, the dominant microorganism in the fermentation process of Pu'er tea is black Aspergillus, while in Hunan Dark Tea, it is Candida. Due to these differences, the intrinsic changes in the tea and metabolic products are distinct. Of course, if Pu'er tea were fermented under low temperature, low humidity, and for a short period, its quality characteristics might be closer to those of Hunan Dark Tea.
In addition, the difference in fresh leaf raw materials between Pu'er tea and Hunan Dark Tea is one reason for the clear differences in tea soup concentration, color, and durability. Pu'er tea uses large-leaf varieties, which contain higher levels of polyphenols compared to the medium and small-leaf varieties used for Hunan Dark Tea. Therefore, the tea soup's concentration, color, and durability are stronger in Pu'er tea.
In summary, due to differences in fresh leaf raw materials, processing techniques, and the physical and chemical changes mechanisms they form, two distinct tea products with different quality styles are produced. Both have their unique characteristics, and it's not appropriate to directly compare which is better or worse.
In terms of quality style: Pu'er tea has a rich and thick taste, while Hunan Dark Tea is sweet and refreshing; Pu'er tea can withstand many infusions, while Hunan Dark Tea has a long-lasting aged flavor (sweet and pure tea soup with prominent and lasting aged aroma).
1. Color difference: Pu'er tea changes from green, indigo, to chestnut red, deep red, and dark red, while Hunan Dark Tea changes from orange yellow to orange red.
2. Taste difference: Pu'er tea has a strong taste upon entry, while Hunan Dark Tea is sweet and pure. Pu'er tea can withstand many infusions, while Hunan Dark Tea has a long-lasting aged flavor, especially in the sweetness and purity of the tea soup.
3. Aroma difference: The aroma of Pu'er tea is quite complex, varying due to factors such as region, processing method, storage location, and storage duration. Overall, it feels rich and substantial. In comparison, Hunan Dark Tea is relatively simple. To summarize, the aroma of Pu'er tea is deep and profound, while that of Hunan Dark Tea is relatively open and refreshing.
4. Difference in leaves at the bottom: Leaf characteristics depend on the raw material and processing technique. Fresh leaves used for Yunnan Pu'er tea are often entire buds, one bud with two or three leaves, and do not require chopping. In contrast, Hunan Dark Tea requires the inclusion of stems, and the processing involves chopping, leading to less intact buds and leaves (higher-grade dark tea may have more intact leaves at the bottom).
5. Functional difference: First, it manifests in the nature of the tea. Modern Pu'er ripe tea, especially older teas, create a warming sensation when consumed, while Hunan Dark Tea provides a cool, sweet, and refreshing effect. Pu'er tea has a unique role in protecting digestive functions, characterized by no stimulation to the stomach and not harming the stomach even with prolonged consumption. Hunan Dark Tea, especially aged dark tea, has a unique therapeutic effect on gastrointestinal diseases. Both have the effects of lowering blood pressure and lipids and can promote fitness and beauty, making them health-promoting beverages suitable for long-term consumption. Additionally, Hunan Dark Tea has a stronger effect in lowering blood sugar and treating diabetes.
Liu Bao Tea is produced in areas like Xunjiang, Hejiang, Guilin, and Yujiang in Guangxi, named after its origin in Liu Bao Town, Cangwu County, Wuzhou City, Guangxi.
The production of Liu Bao Tea has a long history. It was mentioned in “Wu Jun Record” during the Southern and Northern Dynasties, describing a type of large-leaf tea called Gualu Mu, where the leaves are made into powdered tea, transforming from bitter and astringent to mellow. In the fifth and sixth centuries, people in Guangdong and Guangxi had the habit of drinking tea and would make compressed teas in the form of balls, cakes, and cubes. Those produced in Guangxi were likely Liu Bao Tea.
Liu Bao Tea has a coarse shape, a black and lustrous color, a reddish-yellow broth, a mellow aroma, a rich, mellow, and refreshing taste, and a yellow-brown leaf base. The finished tea has a black and lustrous appearance, sometimes with golden flowers (i.e., yellow fungal spores), a deep and rich broth, an aged and mellow aroma reminiscent of betel nut, a sweet, mellow, smooth, and cooling taste, and a red-brown leaf base. It is suitable for long-term storage, improving with age.
The processing technique for Liu Bao Tea raw tea is extremely similar to that of Hunan Dark Tea. The processing technique for Liu Bao Tea is: fresh leaves – fixation – initial kneading – wet-piling – secondary kneading – drying. This is consistent with the processing technique for Hunan Dark Raw Tea. Wet-piling and drying with pine wood fire are key procedures in Liu Bao Tea processing. According to research, the mechanism of wet-piling in Liu Bao Tea is consistent with that of Hunan Dark Tea, so Liu Bao Tea shares a similar quality style with Hunan Dark Tea.
After Liu Bao Tea is compressed into shape, it has a lighter compression degree and a higher moisture content. It is dried using natural air-drying, allowing the growth of fungi similar to those