Category Archives: General Tea Background

Plant cell structure under a microscope.

Scientific Studies of Tea

As a tea drinker, we rarely to stop to think about who is studying our favorite beverage and what are they learning. The complexities of the tea leaf itself and what drives those complexities are head spinning. So, it is truly exciting to find a translation in English of a qualitative review of who has been conducting scientific studies of tea and what they are learning about the plant and beverage.

White tea drying in China.

Published in the Frontiers of Plant Science, a group of scientists from the Hunan Agricultural University in Changsha China, did a review of the past decade of scientific studies of fresh tea leaves[1]. So, what did they find?

Who is Studying Tea?

It should not surprise anyone that most of studies of tea are coming out of China. They are largest and oldest manufacturer of tea, with the Chinese tea industry having an estimated total revenue of $99.8 billion in 2022. This accounts for approximately 1/3 of the total tea industry worldwide. The Chinese national government and local governments have designated the tea industry as a critical economic driver, making available government money for scientists to research tea. Interestingly over the past decade, while China logged over 600 studies, the United States actually managed to do 17 studies and worked in collaboration with the Chinese on enough of their studies to actually get mentioned by the authors. So, if you want to study tea in the US, head to the University of Florida, Rutgers University, Montana State University and the University of Georgia.

What is being Studied about Tea?

Both 2007 and 2017 seem to be watershed moments in the scientific study of tea. In 2007, the Human Metabolite Database was created. This freely available electronic database gives scientists detailed information about small molecule metabolites found in the human body. With access to this database, the study and identification of metabolites in tea as well as the effects of those metabolites on humans became the largest types of studies over the past decade. In 2017, the first full genome assembly of the tea plant was published which caused the expansion of studies into gene expression under stress caused by climate, soil and other changes. This category is expected to expand in the coming years as the publishing of studies, not surprisingly, decreased during the Covid pandemic.

Tea fields in Fuding China.

The authors project based on current trends in topics in scientific literature that we will see the publication of more studies in the future around the metabolic effect on the tea plant of cultivation treatments (watering schedules, fertilization, pesticide, and fungicide applications).  Other studies will include resilience of plant gene expression in the face of climate change, as these studies were starting to pick up in 2019 and again decreased dramatically because of the Covid pandemic.

As an avid tea drinker, these findings and projections bring me great joy and hope in the future for my favorite beverage.


[1] YiQuin Chin, YunFei Li, ChengWen Shen, and LiZheng Xiao, “Topics and trends in fresh tea (Camellia Sinensis) leaf research; A comprehensive bibliometric study”, Frontier of Plant Science, Volume 14, April 6, 2023.

Panamanian tea field with flag

Visiting a Panama Tea Plantation in Boquete

Panamanian tea is not a phrase you hear in the tea industry as I write this blog. However, if one entrepreneur has his way that may change in the future. During our travels, regardless of country, David and I are always looking for tea. We were shocked to find a tea tour offered in Western Panama. It’s available in a larger portfolio of tours alongside zip lining, coffee tours and general outdoor eco-adventures in Boquete. Even with the $30/person price tag, David and I had to find out if they really had true tea.

Panamanian Tea Tour – Boquete, Panama

Panama is better known worldwide for its Geisha or Gesha Coffee. As a side note to my tea drinkers, find this coffee – it tastes like tea! In fact, it was this association with tea that led to the tea plantation experiment. It’s also hardly a surprise that Gesha Coffee got rebranded as “Geisha” to improve marketing in Asia, especially Japan.

So, finding a steep mountainside of Camelia Sinensis Assamica in Boquete, growing at about 5,700 ft above sea level, was truly a delight.

Planting Tea in Panama

Boquete is a rural town about 9 hours by car outside of Panama City. The closest airport is about 45 minutes away in the town of David. It is high elevation, wet and sunny with plenty of fog, especially during the rainy season. This climate is similar to Sri Lanka or the Nilgiri region of India. It is home to large number of coffee farms, most of them owned and run by Americans and Europeans, and a few by Panamanians. Kotowa Tours (aka Boquete Tree Trek) is a Panamanian company, with a Panamanian owner, that has been around for over 100 years. While their properties are for outdoor recreation, like zip lines and hiking, they are growing coffee, chocolate and tea there as well.

Octavian and Hillary in the tea fields looking at a young tea plant.

Our tea tour began with a walk through the tea fields with Kotowa’s tea master in training, Octavian. Currently, plants cover less than 1 acre, but there is plenty of room to grow. The first of the tea plants went in 7 years ago and Octavian and his team of four other grounds keepers have been diligently collecting seeds and replanting every year progressing higher up the mountain. The plants are in beautiful shape, with just a few grasshoppers leaving an occasional bite mark on some of the leaves. The biggest “pests” are armadillos. They periodically burrow in to the ground near the roots killing a tea plant here and there. It was fitting to be climbing through the fields, only to be hit with incoming morning mountain fog and rain. The plants are truly in their perfect environment and their huge dark green leaves let you know it.

Harvesting and Manufacturing Tea

The plants are so happy that Octavian and his team are harvesting roughly every 25 days, year round. Now, that is not unheard of in Sri Lanka, India and parts of Africa. So we posed the questions about which months produced the better tasting harvest. It was not surprising to hear the December-March produce a sweeter tea since those are the “dry” months in Panama.

The entire harvest and processing is done by 5 people. They are plucking, rolling and shaping the leaves by hand. With only an acre, their largest given harvest is only about 250 kg (roughly 550 lbs) at a time. That will become roughly 50 kg of finished product, which is only 110 pounds of tea. This is very manageable for a team of 5 people. From harvest to finished product, it is only 4 days, with most of the time spent waiting on the tea to dry.

The processing of the tea will likely change as the tea plants expand and there is more to harvest and produce. Plucking will remain by hand as the mountainside is too steep for machines. We had a good laugh about finding tea manufacturing machines with instructions in English\Spanish and available replacement parts in the Western Hemisphere – there aren’t any.

Cupping Panamanian Tea

Dried and twisted green tea leaves in a glass container

Kotowa is currently trying to make white, green, oolong and black tea. With the help of an experienced tea master from Taiwan, Octavian is playing with withering times, baking times, and steaming techniques. We had a great time talking about his lessons learned and where he thinks he will continue to play and fine tune flavor.

Given his tea master is Taiwanese, it was no shocker that the teas where lighter and smoother, mimicking Taiwanese tea. The green tea has a real chance of being a unique flavor profile, as they are steaming the green, which is causing it to taste and smell like the corn meal on the outside of a Panamanian tamale (this is a sweet vegetal taste because the tamales are steamed in banana leaf wrappers).

We expect Octavian will have success in making uniquely Panamanian tea and wish him the best of luck!

Floral Tea: History of Brewing Flowers

With Valentine’s Day just around the corner, we’ve been getting into the spirit by brewing up some of our favorite floral tea blends. From classics like Jasmine Green and Lotus Blossom to newer favorites like The Rose Garden, there are teas for lovers of almost every kind of flower you can imagine. And as it turns out, the practice of using flowers to flavor tea blends is nearly as old and widespread as the art of tea itself.

The Rose Garden Tea Dry Leaf and Brew
The Rose Garden Tea Dry Leaf and Brew

Some of the earliest records we have on the use of floral infusions come from Persia, during the Sasanian Empire (224-651 CE). Although Persian royalty had long been known for their love of beautiful gardens, it was during this era that methods of steaming petals to make rosewater were perfected. Rosewater was soon used in everything from perfumes to cosmetics to medicinal decoctions, and its popularity spread throughout Europe, northern Africa, and western Asia. Ancient Greeks and Romans associated the flower with Aphrodite (also known as Venus) and like the Persians made broad use of the flower in almost every application imaginable. Roses continued to be used worldwide in folk remedies over the centuries, and with the introduction of tea culture into Europe it was only inevitable that the two would be combined. Western recipe books and home journals begin suggesting the additions of rose petals to tea blends by the early Victorian era, gaining special popularity around the turn of the 20th century. Today, rose petals are one of the most popular additions to teas of all types, as well as tisanes.

Jasmine flowers scenting green tea
Jasmine flowers scenting green tea

Across the world in China, tea merchants have been using jasmine flowers to scent and blend with green tea since the Song Dynasty (960-1279 CE). This era also saw the growing popularity of chrysanthemum teas and tisanes, as the lightly fragrant yellow blossom was prized not only for its medicinal properties but its sweet and delicate flavor. Chrysanthemum tea soon spread to Japan by the 5th century, and also to Korea, where it remains popular alongside other flower tisanes such as peach and plum blossom.

Two other flowers that are commonly seen in tea blends and tisanes are chamomile and lavender, both of which have long been thought to possess calming or sleep-inducing properties. Like roses, lavender and chamomile blossoms have been used for medicinal purposes since antiquity, with ancient physicians such as Dioscorides prescribing them for all sorts of ailments from indigestion to headaches. Preparing these blossoms for consumption by infusing them in boiling water was commonplace, and they were often paired with herbs like mint, sage, and rosemary for a more palatable and very fragrant tisane.

As all this history attests, flower petals and tea can make for delicious and beautiful combination. We especially love brewing floral tea in either a glass teapot or gaiwan to fully appreciate the appearance of the blossoms as they infuse. During a long and dreary winter, flower teas are just one small way to look forward to the coming days of spring.

By: Jen Coate

Vietnam: Snow Shan Tea

Vietnam is a country long steeped in surprisingly ancient tea traditions, although it is often overshadowed by such industry giants as China, Japan, and India. But unknown to many Western tea drinkers, this small country has a lot to offer when it comes to tea varieties, one of the most impressive of which are the Snow Shan teas. Named for the fine white down that can be observed upon the plucked leaves, these teas are truly unique not only for their excellent flavors, but for the special cultural significance that they hold for the people of Vietnam.

Snow Shan teas are grown high in the mountains of northern Vietnam, where the country is bordered by the eastern edges of the Himalayas. Although this tea region crosses multiple provinces, the largest growth area of Snow Shan is in Ha Giang, Vietnam’s northernmost point. Throughout the country, differences in climate, geography, and terrain produce unique impacts on the tea’s terroir, which in turn leads to many variations in aroma and flavor. In Ha Giang, many of the wild tea trees from which Snow Shan is harvested are over a hundred years old (some are said to be nearly a thousand) with massive trunk sizes over a meter in diameter. A far cry from the small shrubs from which many industrially-produced teas are farmed! These ancient trees are carefully tended by the indigenous ethnic peoples of the regions in which they are grown, such as the H’mong or Dao, who carry with them many generations of Vietnamese tea tradition.

Snow Shan White Tea Buds

Among the subgroups of Snow Shan teas, one of the most interesting and outstanding offerings from Ha Giang are Snow Shan White Tea Buds, grown on the high mountain slopes of Mt. Chiêu Lầu Thi in the rural district of Hoàng Su Phì. Rather than plucked leaves, these woody small bundles (resembling pinecones) are actually harvested from unopened stem buds, taken from the main trunk and branches of the ancient tea trees. When infused, they release a light and delicate aroma in a pale golden liquor, with sweet floral and woody flavors leaving a lingering aftertaste of subtle spice. We are not exaggerating when we say that there is no tea anywhere in the world that can quite compare!

High Mountain Snow Shan Black

Another fantastic example of the best qualities of Vietnamese tea is the High Mountain Snow Shan, a black tea with large full leaves from mature trees grown at elevations around 1,400 feet high. The resulting tea is very smooth and mellow, but still rich with complex flavors and aromas.

While still a relative newcomer to the modern orthodox tea market, Vietnam has a lot to offer when it comes to truly unique tea experiences. If you have yet to try Vietnamese tea, Snow Shan varieties can be a wonderful place to start.

By: Jen Coate

View inside an aged oolong tea cake and its brew.

Aged Oolong Tea

2009 Aged Oolong Tea CakeBack in December, we wrote about aged white tea cakes, a recent innovation out of Fujian, China that has slowly been gaining popularity here in the United States. Like puerh, aging white tea can give it a whole new array of flavors and complexities. But puerhs and whites aren’t the only teas that can benefit from aging. Unknown to many Western tea drinkers, the tradition of aging oolongs in Taiwan and China is nearly as old as oolong tea itself.

Much like white tea (and in contrast to puerh), aged oolongs do not require fermentation to kick off their processing. Instead, they are traditionally baked or roasted over charcoal and carefully kept sealed from light and moisture. Too much moisture will produce a distinct tartness or sourness that can overpower the delicate complexities acquired in aging. Some producers of aged oolongs will re-roast their teas every few years to ensure a proper dryness. But this step is not always needed so long as the tea is stored properly and in the right environment.

Generally, an aged oolong is not considered ready for consumption until it is six to eight years old – although some connoisseurs argue that oolongs should wait until they are at least thirty to lose their “greenness”. Regardless, a well-stored oolong will continue to age and improve for many decades. The resulting flavor is both mellow and complex, and can contain notes of honey sweetness or cooling herbs. Superior aged oolongs have a soft and silky mouthfeel and a pronounced smoothness.

Like puerh and aged white teas, not every oolong is considered suitable for aging. The leaves must be of a high-enough quality, and the plucking and processing done with special care, so that the aging tea will be able to acquire the prized complexities and flavors and not merely taste stale. Traditionally, high-mountain Taiwanese oolongs, like Dark Roast Alishan, with a moderate to heavy roast are considered very suitable, as well as “rocky” teas from mountainous regions like Wuyi in the Chinese mainland. The flavors that are already naturally imparted through these high-elevation, mineral-rich terroirs are perfect for development through aging.

View inside an aged oolong tea cake and its brew.Although still a relative rarity in the U.S., aged oolongs are slowly coming into the western market, mostly through specialty tea houses. Some are sold loose, in their semi-balled form, while others are compressed into cakes of varying shapes and sizes. Here at Dominion Tea, we are excited to now be offering 2009 Aged Oolong Cakes, which are available for both online orders and in-store pickup. Whether you’re new to aged teas or a seasoned veteran, aged oolongs are a wonderful way to explore a corner of the tea world not often noticed in the West.

By: Jen Coate