Oolong Tea Oxidation Chart

Awhile back, a discussion about whether Spring Pouchong is more correctly classified as an oolong or as a green tea pointed out the importance of oxidation for oolongs. I began digging around and found various standards, opinions, ideas, etc., about what range of oxidation oolongs should have. There is a general rule of thumb, but rules are meant to be ignored, broken, and stood in the corner until they behave. And it seems that a number of people have their own ideas of what that rule is in the first place. Nevertheless, an oolong tea oxidation chart seemed in order here, consolidating the various versions out there into one.

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Oxidation in Brief

Oxidation is where the tea leaves have been rolled to bruise them after withering and to facilitate the interaction of the leaves with oxygen in the air. According to some sources, the oxidation turns the leaves darker, while others say it does not, that it is the roasting that darkens the leaves. Either way, controlling the process is such an important part of making oolong teas that oolong aficionados will often buy based on who the tea master was. Oxidation, as well as the roasting, affects both the flavors and lifespan of the teas. More highly oxidized and roasted teas tend to have deeper flavors, more nutty, richer, and a longer shelf live, with long-term storage being a distinct possibility.

Sometimes oxidation levels are expressed as percents and other times by terms like “light,” “medium,” and “dark” (based on the color of the tea leaves and therefore not necessarily accurate). One source says oolongs are oxidized between 15% and 80%. Another says 30% to 70%. Another says that the oxidation can be as light as 8% and as dark as 85%. Still another says, “Oxidation can range from 15% to 70%, although 20-30% is most common for oolong teas.” [I have to discount the article that claims oxidation can be as low as 2% for oolongs, since that amount can occur in green and white teas.] How much the leaves are oxidized depends on the cultivar, the desired flavor and aroma outcome, the customer preferences, and even tradition. How well this is done depends, as previously mentioned, on the tea master in charge of processing the leaves.

Tea Chart

No, I am not going to present an encyclopedic listing here. Just hitting some highlights and the better known oolongs.

Note: in some parts of the world oxidation is referred to as fermentation; for the purposes of this article we are staying with the term “oxidation.”

Tea Average Oxidation Level More Info
Wuyi Oolong Family
(Rock/Crag Tea, Yancha)

Includes:

  • Da Hong Pao (Big Red Robe) tea family
  • Rou Gui tea family
  • Shui Xian tea family
  • Shui Jin Gui (Golden Turtle)
  • Tie Luo Han (Iron Monk)
  • Bai Ji Guan (White Rooster)
  • Ban Tien Yao (Middle Sky)
  • Golden Buddha
  • 25-50%
  • From northern Fujian Province, China
  • Part of tea family called Mingbei Oolong.
  • Leaves are long, curly.
  • Unique taste (Rock Rhyme or Yanyun), due to high mineral content of soil.
  • An extremely complex family of oolongs, with thousands of tea plant cultivars.
  • Golden Buddha is a new cultivar developed around early 2000s by Wuyi Shan Tea Research Institute
Tieguanyin (Chinese)
  • heavy
  • From Anxi Province, China

Styles:

  • Green (bouquet)
  • Browned (roasted)
Qing Cha – aka Pouchong, Bao Chong, or BaozhongTypes (based on where grown):

  • Wenshan
  • Nangang
  • Lanyang
  • 7.5-19%
  • 8-18%
  • 10-15%
  • very light
  • From Taiwan
  • the most green of oolong teas
  • Wenshan is most common
Dong Ding
(Tung Ting, “High Mountain”)
  • 20-30%
  • 25-35%
  • 15-25%
  • medium
  • From Taiwan
  • Authentic version is from Dongding Taidi on Dongding Mountain (“Frozen Peak”) at 600-1,200 meters elevation. Tea grown at lower elevations is Dongjiao Cha (“Frozen Leg Tea”).
Gaoshan Tea (High Mountain)

  • Meishan
  • Alishan – best
  • Yushan
  • Wushe
  • Lishan
  • Medium (but can vary)
  • From Taiwan
  • Grows at 1,000 meters elevation
Tieguanyin (Taiwanese version)Varieties:

  • Mu Zha (Wooden Gate) – best
  • Shi Men (Stone Door)
  • Others
  • Medium (has been more varied lately)
  • From Taiwan
  • All versions are ball-shaped oolong teas.
Champagne Oolong (Xiangbing)White Hair Oolong Tea (Baihao)Puff Tea (Pengfeng)
  • 50-70%
  • heavy
  • From Taiwan
  • Considered exotic
  • Made of young tea shoots (one-bud-and-two-leaves) rather than more matured leaves typically used for oolongs
  • Closest to Chinese black (red) tea
Oriental Beauty
(Dongfang Meiren, White Tip Oolong)
  • 50-60%
  • +/-70%
  • highly oxidized
  • From Taiwan
  • Part of the “Champagne Oolong” group
  • Natural fruity aromas, sweet tasting bright-reddish orange liquid.
Cui Yu (Jade Oolong)
  • light
  • From Taiwan
  • Officially named TaiCha #13 in 1982.
  • Slower growing than Jin Xuan but 20% faster than Chin Shin.
  • Unique and intense floral/orchid aroma.
Four Season Oolong
(“Da-To-Hwei son”)
  • 20%
  • light
  • From Taiwan
  • A naturally hybrid cultivar found by a tea farmer.
  • Fast growing.
  • Intense floral/fruity aroma.

Bottom Line

It’s a changing tea world out there. Tea masters have their own ideas about what is best, but they also respond to customer feedback. My recommendation is that you try out several and find what suits you best. And remember that oxidation is just one part of the picture. Roasting is another key, as is the cultivar. Happy hunting.

About Janice and Stephen Shelton

Purveyors of Premium Teas
This entry was posted in Oolong Teas and tagged , . Bookmark the permalink.

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