Oolong Tea 101

Oolong tea, popularized in China and Taiwan, is slowly making its way to Western culture. Learn more about the history, flavors, and how brewing of this incredibly diverse category of tea.
Oolong Tea 101 - Mosi Tea

Even if you're new to tea, you likely are already familiar with the black and green tea varieties. But you may not know that there are actually four main tea types, which also include white tea and oolong tea. Each of these varieties, derived from the Camellia sinensis plant, presents its own unique flavor profile and potential health benefits. In this blog, we will explain what oolong tea is, describe its robust history, as well as provide our best tips for oolong tea consumption.

What is Oolong Tea?

oolong tea

A traditional Chinese tea, oolong tea — like green tea and black tea — is made from the leaves and stems of the Camellia sinensis plant. However, it’s processed differently. Oolong tea is only partially fermented (unlike black tea, which is fully fermented, or green tea, which does not undergo fermentation). Oolong tea may end up with more green or black tea characteristics depending on how it is processed. Oxidation levels vary greatly depending on the style of the tea master; some seek a fresher, green tea flavor, and others a richer black tea flavor.

How Oolong Tea is Made

Oolong tea leaves are harvested during spring, allowing them to mature for longer than white or green tea. The leaves are withered, partially oxidized under the sun, and shade dried. These tea leaves are then shaken in a basket, thus bruising the leaves and allowing even oxidation. To stop the oxidation process, tea makers skillfully hand roast the oolong leaves in several steps.

Flavor of Oolong Tea

Oolong tea represents a wide variety of tea, and thus can vary greatly in flavor. A cup of oolong tea can taste fresh and bright, or more toasty and woodsy if it was oxidized for a longer period of time. In addition to the oxidation process, the rolling process alters the flavor of the tea. Through hand pressing, the tea leaves are rolled into shapes similar to small black dragons, which also explains the name oolong — it is also called wu-lung tea, which comes from two words that translate to “black” and “dragon.”

History of Oolong Tea

When it comes to the origin of oolong tea, you have to learn three theories: tribute tea, Anxi, and Wuyi. In the tribute tea theory, oolong tea is believed to directly come from Dragon-Phoenix Cake tribute tea. This tribute tea had two types: “Dragon” (or Long) and “Phoenix” (or Fong). As loose tea became popular, the name became Black Dragon tea — more popularly known as oolong tea — because of the dark and curly leaves as a result of processing.

Another theory worth knowing is the Anxi theory, which says that the first-ever discovery of oolong tea happened in the Fujian province’s Anxi region. A man known as Wuliang, Wulong, or Sulong let the leaves oxidize by accident because he got distracted while harvesting. When he returned to his withering tea leaves, he discovered that they were already starting to oxidize. 

According to the Wuyi theory, oolong tea’s name was derived from the Wuyi mountain region. Tea Tale, Wuyi Tea Song, and other poems from the Qing Dynasty make this theory more credible. The peak of oolong teas’ popularity also happened during this dynasty when the emperor Qian Lung was captivated by the beauty of Ti Kuan Yin, the Iron Goddess of Mercy, which is also a type of oolong tea.

During this time, the gongfu tea ceremony was also relevant and popular. Oolong tea would be served using Yixing teapots that were carefully handmade from purple clay. The teapot’s design only allowed one type of tea to avoid flavor contamination while also seasoning the teapot.

Oolong Tea Today

With the immense popularity of oolong teas in the mid-1990s, tea production extended to Taiwan. The profiles and quality of oolong teas grown in Taiwan tend to vary because of the changing weather.

Other Asian countries like Nepal and India have also been engaged in the cultivation of oolong tea. However, the most impressive oolong teas today are still those from the Anxi and Fujian regions of China and Taiwan.

As tea culture has begun to infiltrate the West, Oolong tea has begun to make its way across the world. Thanks to its incredible diversity and the technicality required to process a perfect blend, this category of tea is known as an option for the true tea aficionados. Further, the many health benefits of drinking oolong tea have increased its popularity.

Oolong Tea Types & Variants

The cultivation and harvest of oolong teas mainly happen in the different areas of China and Taiwan. However, regions where these tea leaves grow have different weather conditions. As a result, you can try a wide variety of oolongs, such as roasted, floral, and other interesting flavors and aromas.

Chinese Oolong Teas

Three prominent oolong tea varieties are Phoenix tea (Dan Chong), Wuyi oolong tea (Da Hong Pao), and Iron Goddess of Mercy tea (Ti Kuan Yin). The production of Phoenix oolong tea is in China’s Guangdong province.

Harvested from a single bush, Phoenix oolong teas would have a different taste for each batch. While some Phoenix oolong teas create a floral flavor like orchids and orange blossoms, others have a bit of spiciness and fruitiness like ginger and grapefruit.

Wuyi oolong tea — also called Da Hong Pao — which is dark and significantly oxidized. With the purported health benefits of oolong tea, legend says that during the Ming dynasty, Da Hong Pao helped save an emperor’s mother. It’s also claimed to be the favorite of former President Nixon.

This tea gives you a unique earthy flavor, with some hints of molasses, stone fruit, and brown sugar. It also offers the perfect combination of sweet and mellow. Da Hong Pao joins the list of the most expensive teas worldwide. 

Meanwhile, the Iron Goddess of Mercy tea has been considered the most well-known Chinese tea. Its name was taken from Kuan Yin, who was treated like the female Bodhisattva of Compassion. According to the legend, a young farmer found Kuan Yin’s iron statue in a dilapidated temple. He took the effort to clean and reconstruct the statute even if he didn’t have the money to do it. Because of his kindness, the Bodhisattva gave him a small tea plant as his reward. The farmer then nurtured the plant and created the name Ti Kuan Yin. He shared it with other locals, and as the tea became so famous in the community, the farmer also experienced prosperity. Now, the Iron Goddess of Mercy remains a favorite among tea lovers with its floral flavor and aroma like that of an orchid.

Taiwanese Oolong Teas

Some of the famous Taiwanese oolong teas include Jin Xuan tea, Gaoshan, and Bao Zhong or Pouchong. Also called Golden Daylily tea, Jin Xuan tea offers a light, creamy, and floral flavor. This milk oolong tea is also cultivated in Thailand. Once the tea leaves undergo oxidation for a specific period, they deliver that natural milk-like flavor.

Another Taiwanese oolong tea is Gaoshan, also called High Mountain oolong tea. These seasonal teas are cultivated at altitudes as high as 3,300 feet and above. Tea farmers harvest Gaoshan twice every year, so the tea is called both spring Gaoshan and winter Gaoshan.

As the tea leaves are dried on a huge tarp and oxidized, they produce aromas of jasmine, geranium, and rose. Then, they’re folded and withered for as long as eight hours. You’ll love Gaoshan tea for its sweetness and crispness with hints of pine and flowers. It also offers a smooth and buttery aftertaste.

Meanwhile, Bao Zhong is known as green oolong tea because of its similarity to green tea in terms of flavor, aroma, and color. Compared to other oolongs, Bao Zhong is less oxidized, so it doesn’t have a bitter taste. It also produced the same unique floral aroma and sweetness of oolong.

Darjeeling Oolong

One Oolong variety which may sound familiar to you already is Darjeeling, the oolong tea famously grown in India. Mosi Tea proudly offers a hand-picked, loose leaf Darjeeling oolong from the Himalayan foothills of India. This rare variety of loose leaf tea is grown in an area typically known for its black teas, giving it a woody tobacco taste paired with the floral, fruity kick reminiscent of green teas.

Oolong Tea Tips & Preparation

Generally, oolong teas are prepared with 185 to 206º F water and steep for two to four minutes. However, the temperature differs based on factors like the type of oolong and the oxidation.

For the Mosi Everest Oolong, we recommend about a teaspoon of loose leaf oolong for 8 oz of water, at 185F. Using our portable infuser, you can fill the sieve and steep for about 2-4 minutes for a rich woody, sweet cup with muscatel notes.

Caffeine Content

Compared to coffee, oolong tea contains lower caffeine levels. If coffee offers 95 to 200 milligrams of caffeine for every 8-ounce serving, oolong tea only has around 35 to 55 milligrams per 8-ounce serving.

The caffeine content of oolong might vary depending on the water temperature, according to Taiwan’s Tea Research and Extension Station (TRES). Thus, it may fall between 100 and 300 milligrams per liter. While lower in caffeine content than coffee or matcha, oolong tea contains l-theanine. L-theanine is a compound that aids in focus without the jitters associated with caffeine.

Health Benefits

Like other types of tea, drinking oolong tea is associated with a number of health benefits. Research has shown that drinking just one or two cups of oolong tea per week leads to lower risk of high total cholesterol. Because of oolong's impact on cholesterol, studies have concluded that those who drink one or more cups of oolong tea per day have a lower risk of heart disease.

Several studies have also found that drinking oolong tea may improve bone mineral density, which is often a concern for aging women.

Because it contains l-theanine, oolong tea may also aid in stress relief. Other possible benefits of consuming oolong tea include healthier gut bacteria, lowered risk of type 2 diabetes, and prevention of cavities thanks to its fluoride content.


If this blog inspired you to try your first cup of oolong tea, we recommend starting with a loose leaf to experience the full flavor of a robust oolong. Try out our Everest Oolong, a woodsy and complex blend roasted to perfection.


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