Steaming vs fermenting vs Roasting for Japanese tea
Tea leaves after being plucked from the plant are sent for processing. The processing involves a bunch of methods through which tea leaves are transformed into dried and preserved leaves for later brewing. The tea from the same plant, Camellia Sinensis are differentiated based on the process they undergo, which involves oxidation of leaves of different levels, formation, and drying.
The first step for any kind of tea leaves is either steaming, fermenting, or roasting, depending on the kind. The steaming process is fixed for green tea, black tea leaves go through the fermentation process, and roasting is dedicated to oolong tea leaves. All these have the same purpose, to inactivate enzymes that speed up the decaying process and change the components. However, each tea has its method because it also preserves the desired taste and color in each tea.
The steaming process is used crude tea leaves because it eliminates the grassy leaves smell, produces green tea aroma, inactivates enzymes in leaves, and makes the leaves easy to use later. Just after picking, green tea leaves are sent to the factory for processing. They are steamed in high heat immediately, which helps in activating enzymes and enhancing the aroma.
Enzymes, if still present in tea leaves, start to change the component and oxidize the catechins with oxidized polyphenol. Catechins are an essential ingredient in green tea as it has numerous health benefits, and if destroyed, it does not give benefits but disadvantages. It works as an antioxidant in your blood and gets rid of oxidant radicals. Therefore, steaming is important to keep the catechins in tea and get benefits.
Most of the time, the steaming process depends on the tea plant’s growing conditions such as environment and elevation. Different kinds of green tea have a period of steaming. Some are steamed for half a minute and some to a full minute or more to preserve maximum taste and enhance qualities.
The more it is steamed, the easier it is for leaves membranes to break in later processes and release flavor. Shorter steamed has a lighter color and a higher estrogen level. At the same time, steamed leaves have a more greenish color, low astringency level, and smooth liquid. Some green teas are steamed twice for the better effect and different flavors.
Here are examples of steamed tea we carry:
Black tea leaves are not steamed therefore hold distinct qualities that are obtained with fermentation. It is also called fermented tea because it goes through fermentation to stop enzyme activities. Black tea leaves have many catechins which are oxidized and leave an astringent taste. Oxidize from catechins gives the taste and theafrabin; another oxide gives the color to the tea due to fermentation.
Fermentation, in the case of black tea, involves enzymatic oxidation when leaves are dried in the presence of atmospheric oxygen. The heat and moisture evaporate from leaves, and the dry and dark tea leaves remain. Leaves are then oxidized under controlled environment conditions. It can be done on batches or conveyor belts with proper airflow and temperature control.
The level of oxidation has a prominent effect on black tea, and each kind of tea has different levels to get the desired characteristics. The tea when brewed has a darker color and is rich with oxidation and such qualities depend on the fermentation period. Longer time results in a darker and more robust flavor.
There are many tea kinds that do not have the above methods to inactivate enzymes but instead are roasted on an iron plate to get the same result. Roasting is also known as a pan-fried method. You fry tea leaves on a pan with limited heat until they emit aroma and look brownish. Oolong tea and Hojicha green tea are commonly roasted during the processing.
Roasting can be divided into two categories, during processing or after processing. If leaves are roasted during the processing, water reduces from them and results in storage for an extended period. It also removes the raw taste due to heat and thus makes it more suitable to use. Roasting also helps in stopping oxidation, just like other above methods help.
The length and intensity of roasting affect the taste and aroma of the tea. Light roasted will have a faint taste and whereas strongly roasted tea leaves give rich aroma and flavor. Heavy roasting also helps in reducing caffeine levels, which comes beneficial in many cases.
The roasting after the processing has many reasons and foremost is to preserve it for a longer time. It is a great process to make your tea leaves refreshed and prevent decay. Roasting also enhances the flavor to the maximum and gives a new taste.
Here are examples of roasted tea we carry: