Did you know that green tea, black tea, oolong tea, and other teas we usually drink, which differ in taste, aroma, and color, are all made from the same tea leaves?

These teas have different tastes and aromas due to the differences in their production methods.

In this article, we will explain why black tea is called fermented tea and how the aroma of black tea is produced, along with the manufacturing process.

Characteristics of manufacturing process of oxidized tea (black tea)

The fermented tea is tea made through complete enzymatic fermentation.

Contrary to unoxidized teas such as sencha and deep steamed sencha, fermented tea is oxidized and fermented using the oxidizing enzymes in the tea leaves.

Initially, it was an "ingenious process (handmade process)" that originated in China about 200 years ago, but nowadays, it is often made by machine.

There are two main production methods: "orthodox" and "unorthodox," A combination of the two has also been produced.

Here we introduce the traditional "orthodox" method.

Fermentation or oxidation?

Fermentation, as used in the tea world, refers to oxidation caused by oxidizing enzymes in tea leaves, as opposed to fermentation caused by microorganisms (bacteria) such as miso or yogurt.

Oxidation is a reaction in which oxygen and enzymes combine to change the original ingredients.

Microorganisms, such as post-fermented teas, ferment some teas, but the tea industry refers to this oxidative fermentation as fermentation.

From plucking fresh leaves to shipping them

Tea leaves are grown in a tea plantation. The tea leaves plucked in the picking season become Aracha (crude tea) after kneading and drying. Then, through “finishing,” the tea becomes a product to be shipped.

How to make Aracha

The plucked fresh leaves undergo the processes of withering, rolling, ball breaking/sieving, oxidation, and drying in this order to become Aracha. Then, after the finishing process, the tea is shipped across the country.

1. Withering

Wilting the fresh leaves to remove the water content evenly is called wilting.

In the past, the leaves were often dried in the shade, but nowadays, "artificial wilting," in which wilting is carried out in a wilting tank with a large amount of warm air, is used.

2. Rolling

The cells of the tea leaves are broken down and shaped by the oxidizing enzymes in the leaves.

When the oxidizing enzymes are exposed to oxygen in the air, they are activated, and catechins, pectin, and chlorophyll undergo oxidative fermentation. These oxidative enzymes are the key elements that create black tea's aroma, taste, richness, and watercolor and lead to the differences between black and green tea.

The tea is fermented for 45 to 90 minutes. Still, to prevent the oxidative fermentation from advancing too quickly, the tea is put through a ball breaker to suppress the fermentation process, cooled, and then repeatedly rubbed again.

3. Ball breaking/sieving

Since the tea leaves clump together during the rubbing process, they are unraveled to allow for average exposure to air, which further promotes oxidative fermentation. The tea leaves are put through a ball unraveling machine during this process every 20 to 30 minutes.

The tea leaves are sieved through a mesh, and those sieved down are called "under the sieve" and transferred to the following process. The larger leaves on the sieve are called the "top of the sieve" and are returned to the twisting process.

4. Oxidation(Fermentation)

In a fermentation chamber with room temperature set at 25-26°C and humidity at 90%, tea leaves are spread evenly to a thickness of 4-5 cm and left to ferment for 2 to 3 hours. During this process, the green leaves turn a bright reddish-bronze color, and a tea-like aroma waft through the air.

However, if the tea leaves ferment too much, the original aroma of the tea will be spoiled, and the watercolor will turn black. Hence, it is necessary to determine when to stop the fermentation process.

5. Drying

Tea leaves at the end of fermentation still have a high water content, and if they are left as they are, fermentation will continue, so they are placed in a dryer and dried with hot air at a temperature of around 100 degrees Celsius. Drying inactivates oxidative enzymes and reduces moisture to less than 5%.

Finishing

The tea after drying is already called “Aracha,” but it cannot be shipped as a product yet. In the finishing phase, it undergoes sorting/shaping and blending in this order to be ready to ship as a product.

6. Sorting (Grading)

Aracha goes through a sifter several times to be sorted by the size and shape. Sorting classifies the tea leaves into grades. This grade is called “leaf grade.”

7. Blending

The final step is blending the leaves. Over 20 types of tea leaves are used, but the purpose is not to mix various kinds. It is to stabilize the quality by choosing teas from the same production area. Blending influences the price of each black tea, and what matters is how to suit consumer tastes by blending.

Did you know that green tea, black tea, oolong tea, and other teas we usually drink, which differ in taste, aroma, and color, are all made from the same tea leaves?

These teas have different tastes and aromas due to the differences in their production methods.

In this article, we will explain how "green tea (sencha)" and "deep steamed sencha" are made and what the differences are between green tea and deep steamed sencha.

Characteristics of manufacturing process of unoxidized tea (green tea)

Unoxidized tea is made without fermentation by inactivating (stopping the action of enzymes) the fermentation (oxidation) of the enzymes in the tea leaves by heating. The characteristic of unoxidized tea is deactivation, which is not the case with other fermented teas.

Unoxidized tea is most commonly known as green tea (sencha). Originally, Japanese tea was yellow or brown, not green. However, with the invention of the "blue sencha manufacturing method," the beautiful green watercolor, elegant sweetness, and fragrant living green tea as we know it today were born.

From plucking fresh leaves to shipment

Plucked fresh leaves are processed near the production area to “Aracha (crude tea)”, which have undergone kneading and drying. After that, they are further "finished" and shipped as products to various regions.

How to make Aracha

Aracha plays a role of “groundwork” to make delicious green tea. The tea leaves undergo the steps of plucking (picking fresh leaves), steaming, rough rolling, rolling/twisting, medium rolling, fine rolling, and drying in this order to be Aracha.

1. Steaming

Fresh leaves are steamed to inactivate oxidative enzymes.

Steaming the tea leaves evenly without applying pressure keeps them green and removes any foul smell. This process is essential for green tea, and the length of steaming time determines the color, aroma, and taste. The longer the steeping time, the darker the color and the less astringent and fragrant the tea will be.

2. Rough rolling

The leaves are vigorously kneaded and dried with hot wind under an appropriate pressure. This process softens the leaves and reduces their moisture.

3. Rolling/twisting

Rough rolling does not knead the leaves enough. Now the leaves are kneaded only with pressure, with no heat. This process equalizes the leaf moisture and breaks up the leaf cells so that the ingredients come out easily.

4. Medium rolling

Rolling/twisting leaves the leaves shrunk and unshaped. By further kneading in hot wind, the leaves become easy to shape at the fine rolling process.

5. Fine rolling

The tea leaves are rubbed only in a specific direction while promoting drying. This process produces the unique needle-like elongated shape of green tea.

6. Drying

After the tea leaves have been fine rolling, they still contain 10-13% moisture, so they are carefully dried with hot air to reduce the moisture content to about 5%. Finally, Aracha is ready.

Finishing

In the phase of Aracha, the leaves are still irregularly-shaped and moist. It isn't easy to maintain the quality. Here comes the need for the finishing process. In this process, “pre-firing, sorting/shaping, firing, and blending” occur in this order. The shipment follows measuring, checking, and packaging. Finishing enables longer storage and enhances the tea flavor.

7. Pre-firing

Prior to sorting/shaping, the entire Aracha leaves undergo firing (roasting, etc.).

8. Sorting/shaping

After pre-firing, aracha is sifted to remove fine stems, etc., and then sorted by leaf size. The tea is then cut and shaped.

9. Firing

Drying once again with fire improves the shelf life of the leaves and brings out the tea aroma.

10. Blending

As the final adjustment, blending can equalize the composition and quality of the tea. Blending makes a well-balanced tea.

What is Fukamushi-cha?

Fukamushicha (deep steamed green tea) refers to sencha made by steeping (steaming) for two to three times longer than regular sencha.
The rest of the process is almost the same as for regular sencha.

The longer steaming time makes the tea leaves softer and more fragile, and the tea leaves are finer in shape than those of regular sencha.

The finer tea leaves have a larger surface area in contact with hot water, allowing the ingredients to be extracted more quickly, so the brewing time is shorter than for regular sencha.

Why deep steam?

Ordinary "sencha" tea has a harmony of astringency and sweetness, and its water color is light green. However, depending on the cultivar and region of production, some teas had a strong astringency, making them unpalatable to the consumer's palate.

Therefore, tea leaves are steamed deeply to reduce the astringency and bring out the sweetness of the tea. The deeper steaming process makes the tea leaves finer and the color of the water darker green. The brightness of the watercolor was also well received, and "deep steamed tea" quickly became popular.

Green tea leaves proudly produced by green tea farmers and manufacturers wouldn’t come to an end when drinking tea.

Used green tea leaves can be “recycled” in various ways.

Ways to recycle used green tea leaves

Used green tea leaves are nutritious and have effects of deodorization and disinfectant, which is why they have been used in many ways in households for ages.

Let us share some useful ways to recycle used green tea leaves..

Eat

It is said that 70% of the nutrients of tea is left in used green tea leaves, and the whole leftover nutrients can be ingested when eating used green tea leaves.

Add to meals

Used green tea leaves can be a good ohitashi salad with a couple of drops of soy sauce, good furikake rice seasoning when dried, and good seasoning when added to fried rice.

Since the taste of green tea is universal, it can actually be paired with anything.

When mixed in cookie dough or cake batter, Japanese desserts would easily be made.

Remove unpleasant smell

Used green tea leaves can remove the unpleasant smell of fish/meat when simmered together.

Only use a little so the green tea flavor doesn’t get extracted on the fish/meat.

Use for cleaning

Used green tea leaves can be used for cleaning as green tea leaves basically have an effect of deodorization.

To clean the floor and tatami mat

Sprinkle wet used green tea leaves on the floor and/or tatami mats and sweep them with a broom. The moisture of the used tea leaves prevents dust from rising and tiny crumbs can easily be swept as they get caught in the tea leaves.

To clean the kitchen

When you clean the sink with used green tea leaves, it gets amazingly clean.

Used green tea leaves have effects of antibacterial and deodorization, which does a good job getting kitchen tools clean like cutting boards, triangle sink strainers and kitchen drains.

Also, if you clean iron pots with used green tea leaves, that would prevent rust.

Spread out on the fish grill tray

When you spread out used green tea leaves on a fish grill tray, the fishy smell on the tray would easily be removed and the tray would easily get cleaned as the tea leaves absorb fishy oil while grilling.

Frost-free

When you wipe glass and mirrors with used green tea leaves, that would prevent frost as well as they get clean. Especially cleaning bathroom mirrors is recommended.

Use for deodorant

The effect of deodorant that used green tea leaves have is useful in various places.

For closets and shoe boxes

Put dry used green tea leaves in a small bag and place it in closets and/or shoe boxes so it absorbs unpleasant smells.

If you are uncomfortable with smells of shoes themselves, you can put wrapped used green tea leaves directly in the shoes.

To remove smells in microwave

Put used green tea leaves on the turntable in a microwave and turn it on, smells in the microwave would be removed in a second.

Use for veggie/flower gardening.

Nutritious used green tea leaves can be used for these;

Use as fertilizer

Used green tea leaves with rich nutrients can be the natural rich fertilizer. Safe veggies would grow when used for veggie gardening, and flowers in a flower vase can last long when put with used green tea leaves.

Bug protection

Used green tea leaves can prevent garden pests when put on the surface on flower beds.

For beauty

Toner and face masks with green tea ingredients are always popular.

Used as bath salts

Soaking in a used-tea-leaves bath has an effect that’s good for your skin.

The writer has tried that before, and felt his/her skin softer like skin after bath time.

More than these, the gentle aroma of green tea made him/her feel relaxed.

When putting used tea leaves, make sure to wrap them with something so they don’t cause clogging and get scattered.

Used green tea leaves for your bath time bring you 2 benefits: Making your skin look better, and clean the bathtub afterwards.

For face wash

When you soak used green tea leaves in water and wash your face with it, it removes extra oil on your face.

But, those with dry skin would have to be careful.

Some people do face masks with used green tea leaves, we recommend you use them according to your skin type.