I recently visited a friend who supplies us with some of our most popular teas before I left Taiwan on a trip to the USA. And as I sat down at his tea table, he offered to brew a pot of his Top Prize (top 2% of 6000+ entries) winning tea in this spring's Lugu Farmers' Association Dong Ding Oolong Tea competition. At first sip I was very impressed, but also somewhat surprised at the relatively light roasted quality and commented on this. My friend, who regularly achieves high-ranking awards in this competition, proceeded to explain the specific qualities that he aims for, and the process of achieving them in crafting the tea.
As the Lugu Farmers' Association is the world's largest single proponent of traditional Oolong Tea, my friend described the qualities that are sought in this competition. Basically, an exemplary Dong Ding Oolong should be complex, yet well-balanced in all aspects. There should be no singular attribute that significantly dominates over others. There should be a noticeable quality of ripeness and subtle sweetness combined with vibrant complexity of flavor. These qualities are attained by proper cultivation Qing Xin Oolong tea plants, followed by skillful processing. The first step that is essential in the processing is solar withering. This is the foundation of properly oxidizing the leaves. Proper oxidation is what results in the balanced, ripe, mellowed quality in a traditional Oolong. Oxidation of the leaves is paralleled by uniform depletion of moisture from the leaves. After the leaves have been oxidized to the desired degree, they are tossed in high temperature tumble dryers. This is also a crucial step, requiring proper analysis of the condition of the tea leaves and adjusting the timing accordingly. After this, uniform moisture depletion and optimal oxidation is achieved by a long repetitive process of intermittently rolling and drying the leaves. And finally, after the leaves are completely rolled and dried into a small spherical shape, they are roasted at low temperature.
I responded by relating my own perspective on the original reasons why traditional teas are significantly oxidized and roasted. As I see it, traditional products are the outcome of generations of experience, involving quirky mistakes and innovative experimentation. Slowly, discoveries are made and further modified in an attempt to attain optimal overall results. A significant part of this is the premodern methods of preserving food products. It is the curing of foods for optimal storage that results in many types of traditional products of regional origin.
He went on to talk about why greener teas are prone to developing a more noticeable stale flavor as opposed to cured (by oxidation and roasting) teas. It has to do with naturally occurring aromatic oil compounds in the tea plant. When I mentioned that I had read a research article long ago that stated there were more than a dozen volatile aromatic oils found in tea leaves. He replied that there are over 100 fatty compounds found in various types of tea leaves that all contribute to the flavor and fragrance. These compounds transform in the processing of tea leaves. The more processing the leaves undergo, the more these compounds are transformed. Simple enough. But a significant reason for processing tea leaves in order to transform these compounds is to make them more stable, i.e. less volatile. Basically it's the same with fruits and vegetables, but a bit more subtle and complex.
It is this complexity involved in the making of traditional teas that adds value to them. They not only become more stable and less prone to going stale, but there is a richness and complexity of character that results from these traditional curing methods. In the end, there is a special quality in each type of tea, just as there is a special quality in both fresh fruits and vegetables as well as when they are cooked or cured properly.
My friend ended up sharing a small amount of the remainder of this award winning tea that proved to be quite delicious as it transformed in quality over several brews. I proudly took it across the globe to share with a friend in Los Angeles who has appreciated the Dong Ding Oolong that we have shared with him for over a decade.