The 10 Best Oolong Teas in 2023

Things to Consider Before Buying Oolong Tea

Oolong can be fermented between 8% and 70% - some oolongs may be as high as 85% - and it ‘sits’ between green tea which is unfermented and the fully fermented black teas. Like all teas, oolong comes from the Camellia sinesis plant.

Oolong means Black Dragon and it can sometimes be seen written as wulong, which has the sane meaning. In China, Oolong is called Qing Cha.

Oolong was once known as Beiyun Tea and can be traced back to the Fujian Province during the Tang Dynasty (618 to 907). This tea became the first tribute tea during the Song Dynasty (960 to 1279) and eventually the tea became known as Cliff or Wuyi Tea as it had such a different flavor to traditional green teas of the time.

One Emperor sent some compressed green tea (known as a tea cake) to Wuyi and asked for tribute tea. When the tea cake was returned to the Emperor, it was made in a mold which had imprinted the compressed tea with a dragon and phoenix design and after this, the fame of the tea became well spread. Even up to the Qing Dynasty ending in 1911, it was still a tribute tea. In the 1700s, oolong tea production spread to other regions, including Taiwan, who remain Oolong producers today.

How Oolong is Processed and Fermented

Once the leaves are harvested, they are spread out either in the sun or inside to soften the leaves and allow moisture to evaporate from the surface of them. Called withering, this step also allows natural enzymic fermentation to begin and reduces the grassy taste of the tea leaves. The leaves then go through a ‘shaking’ stage in which they are shaken manually or mechanically to improve the oxidation.

The leaves are allowed to rest for the length of time needed for the fermentation for that particular tea. The leaves will turn a darker green or even red color and it is at this stage the flavor characteristic of oolong tea begins to develop.

The leaves are fixed through steaming, in a hot pan or baking – this stage is known as ‘kill-green’ as it stops any more natural fermentation. The leaves then pass through rollers to break them down and intensify the flavor and they then dry in the sun, in a pan or in hot air. The oolong is then roasted or fired to give its flavor characteristics such as smokiness or fruitiness.

Brewing Oolong Tea

A traditional clay tea pot is usually used for brewing oolong. Brewing instructions for a tea will usually be for brewing in the smaller cups that tea is traditionally served in.

Follow the temperature recommendation for your tea – most oolongs brew at around 185°F, so when it refers to boiling water it will be this temperature rather than water at 212°F. If you do not have a thermometer or temperature adjustable kettle, then let your kettle boil and allow it to rest for at least two minutes before using.

The tea pot should be pre-warmed with boiling water and you can then add your tea. Follow the quantity guidelines for that particular tea and then you can adjust later quantities for the flavor you require. Generally, if the tea is larger open leaves, then use up to two tablespoons of tea per 6 oz of water, or one teaspoon for tea that is rolled or balled.

You can pour a very small amount of boiling water onto the tea leaves and pour away immediately. This dampens and washes the leaves and starts the steeping. You can then pour your main boiling water and allow the tea to brew for up to five minutes before pouring. A leaf tea will usually infuse faster than a ball or rolled tea.

Oolong loose tea or tea bags can be reused. Each time you brew, extend the brewing time to take account of the lower strength of the leaves.

Storing Oolong Tea

Oolong is best kept in a cool and dark place to slow down the natural oxidation which continues as it has only been partially processed during fermentation. It should also be kept in an airtight container.

Oolong can be refrigerated as this helps keep it fresher for longer and may even improve the taste of the tea. If you do refrigerate it though, it should stay in the refrigerator as when oolong is warmed and chilled repeatedly it starts to degrade.

Nutritional Content

Nutritional content of oolong tea will vary slightly between the different types, specific nutritional information for teas can be obtained through the USDA Food Composition Databases . A cup of brewed tea contains approximately:

It also contains around 36 milligrams of caffeine.

Oolong tea is also rich in antioxidants called polyphenols such as ECGC, theaflavins and thearubigins. It also contains theanine - an amino acid linked to better mental alertness.

Polyphenols in Oolong Tea

There has been less research into polyphenols in oolong – much research to date has focused on black and green teas. One review showed that those who drank 24 oz of oolong tea a day had a lower risk of developing type 2 diabetes. Similar studies also showed that blood sugar levels were decreased in diabetics who consumed varying quantities of oolong tea during 30-day research studies. However, some studies did not agree with these findings, so research continues in this area.

There have also been positive links between oolong and lower risk of high blood pressure, heart disease and strokes, although again, not all research findings have been able to confirm these links.

Although some research has taken place around polyphenols and cancer risk, the studies have focused on green and black teas rather than oolong. Even though it may be that there are benefits to be gained against the risk of certain cancers, it would take a lot more research before the benefits are confirmed for oolong tea and cancer risk.

Polyphenols have also been linked with better brain health, bone density and brain function.

Oolong Tea for Weight Loss

Oolong tea is thought to be able to decrease the amount of fat absorbed from food and boost metabolism and is linked to a very small weight loss alongside a healthy diet and exercise. There have been a number of studies carried out, with one study showing that oolong tea helped people to burn up to 3.4% more calories each day.

There is still uncertainty has to how much of the effects are caused by the caffeine content of the tea, and how much is linked to its polyphenols. To test this, caffeine alone, and a combination of the caffeine and polyphenols were given to test subjects.

Although both were able to increase calorie burning by around 4.8%, only the combination of caffeine and polyphenols were able to increase fat burning capabilities. This study did not show whether any extra energy was used, or whether it led to substantial weight loss.

Particular polyphenols known as catechins (including ECGC) are also thought to prevent the metabolism from slowing as weight is lost. Potentially this means that continuing to lose weight and keeping the excess weight off may be a little easier.

Safety of Oolong Tea

It is suggested that drinking moderate amounts of oolong tea is likely safe for most adults. Higher quantities of oolong may cause side effects due to its caffeine content. These could include headaches, nausea, problems sleeping, heartburn and confusion.

Caffeine can also have an impact on some pre-existing conditions, such as those with irregular heartbeats, irritable bowel syndrome (IBS), osteoporosis or anxiety disorders.

The caffeine in oolong tea can also interact with stimulants such as ephedrine, estrogens, depression medications, anticoagulants or even antibiotics such as quinolones. It is always worth checking with your health professional if your caffeine intake should be limited due to any existing medical conditions or medications.

Conclusion

In this article we considered some of the evidence for oolong as a metabolism booster and it appears there is some evidence of it providing some benefits alongside a healthy diet and regular exercise. The polyphenols in oolong are also linked with reduction of risk for certain conditions such as type 2 diabetes, although more research is needed.