What are Stem Teas?


Stem teas are a little known secret in the world of tea. These unique teas provide an entirely different flavor profile and they are much lower in caffeine than a regular green tea. These teas are also an innovative way for farmers to prevent wasting resources in the tea production process. 

First, let’s talk a little bit about the history of stem teas. Tea used to be a luxury good. The top leaves of the plant were made into premium sencha teas and the stems were often discarded. Often farmers couldn’t afford to drink the teas they produced, because they could only grow so much on limited land. Some farmers began to brew the stems of the tea plant, so they could enjoy at least some of their harvest. They found that these teas actually tasted quite good, and soon people began taking notice of these stem teas. The stem teas were eventually sold on their own as kukicha.

This tea is called kukicha meaning stem tea or twig tea. When more stems and less leaves are used, the tea takes on less of a vegetable flavor and more of a nutty or summer grass flavor. These teas can be a bit milder, and well suited to someone who is new to tea. The color of the tea becomes lighter and clearer as well. 

One benefit of stem teas is that they can be quite high in minerals. When we visited Mr. Henta in Kirishima, he explained this concept to us. When assessing the quality of a tea plant, he likes to look at the thickness of the stems. Because the stems are how the tea plant delivers minerals from the soil to the leaves, thicker stems are able to transport more minerals. Because these stems are moving minerals around the plant, they tend to carry a high concentration themselves. That’s why stem teas can be higher in minerals than many leaf teas.

Another benefit of stem teas is that they are actually low in caffeine, containing about a quarter of the caffeine in a small cup of coffee. Caffeine is produced by the tea plant to protect its leaves from insects. As a result, the caffeine of a plant is concentrated on the outside of the leaf and not the stems. Teas made from mostly stems and only a small amount of leaves will be quite low in caffeine. Depending on the type of stem tea, you can have different ratios of stems to leaves.

The two main types of stem teas are Kukicha and Karigane. Kukicha is far more common, made from the stems and leaves of almost any tea plant. Karigane is made from the stems and leaves of shaded tea plants, like those used for Gyokuro and Matcha. As a result, Karigane takes on a sweeter flavor and it has a slightly higher caffeine content. 

When we visited Mr. Sakamoto in Shibushi, we were first introduced to the concept of cold brewing Karigane. The cold water extracts the sweeter components from the leaves and stems, so the tea takes on a smooth, even fruity flavor with notes of cucumber and melon. Because this tea is low in caffeine, it’s a great relaxing drink to enjoy in the late afternoon.

To make a stem tea, you have to separate the tea leaves from the stems. This used to be a very labor intensive process but now it is all done by machines. When we visited the producers at Marufuku in Shizuoka, we got to witness this first hand. The stems are pushed through a machine and the stems are filtered out based on their weight and size. These bins will be separated into a few different stem teas based on their leaf to stem ratios. 

Just like leaf teas, stem teas can also be roasted. The end result is called Kuki Hojicha or roasted stem tea. During the roasting process, the caffeine content is actually brought down even further, so this is one of the lowest caffeine teas you will find. The flavor is converted into rich notes of black coffee and dark chocolate. If you are a coffee lover trying to give up caffeine, a tea like the Kuki Hojicha may be a good option for you!