What Is Darjeeling Tea? A Field Report on Withering, Muscatel and Altitude

The plucking season changes the character of the tea

The character of Darjeeling black tea depends on when it is plucked. Spring tea (first flush) has a flavor of citrus and flowers in balance. Autumn tea (autumnal) goes through several hours of fermentation and ends up sweet and fruity.

Choosing by estate

HOJO chooses its Darjeeling one estate at a time. We currently carry lots from North Tukvar, Singbulli, Gopaldhara and Arya. Even within Darjeeling, the estate and the time of plucking change the flavor, so we choose again every year from that year's lots.

How to buy good tea (black tea) from Darjeeling

Women plucking tea at a Darjeeling tea estate

How do you find good tea? The usual method is to taste again and again and settle on an estate that makes tea that tastes good.

However, this method does not work very well. Even at the same estate, the quality of the tea differs enormously from one lot to another.

A tea company like us does not buy every lot. We buy just one lot (about 100kg) out of the several hundred made in a year. In other words, the quality of the lot we buy is everything.

Honestly, the quality of the product comes down to the quality of the manager. Location, type of tea and other conditions matter too, but without a capable manager, no location, however good, will produce a good product.

Read the article: How to buy good tea (black tea) from Darjeeling

Staying at the home of a Darjeeling estate manager

An estate manager at a Darjeeling tea estate

We put the most weight on these points. 1. Whether the manager can clearly explain the principle behind fine muscatel flavor, and in particular, tells us everything without hiding anything. 2. Whether the manager, beyond Indian tea, is eager to learn how tea is processed in other countries. 3. Whether the factory and estate are kept in good order.

When I went to Darjeeling, I visited three estates, and at two of them I stayed at the manager's home (a bungalow).

Read the article: Staying at the home of a Darjeeling estate manager

Is Darjeeling tea an oolong?

Tea leaves spread out on a withering trough

There are three types of Darjeeling tea: first flush, plucked in spring; second flush, plucked in summer; and autumnal, plucked in autumn.

The quality difference between these three seasons comes from a process called withering.

Withering is said to be the most important step in a Darjeeling tea factory. It is even said that good withering all but settles 50% of the quality.

Withering takes a very long time, over 24 hours. Darjeeling tea grows high in the mountains, so the leaves are fairly low in water from the start, and after withering only 30% is left.

Leaves with only 30% water do not ferment much, even when the cells are broken in the rolling that comes next.

Oxidase alone does not explain the aroma of fermented tea. The key is the science of withering

As withering goes on, the leaves lose water and suffer dehydration stress. As a result, the cell membranes let more through and grow looser. Enzymes kept apart until then can now touch the aroma precursors they act on for the first time.

In the tea leaf, most aroma compounds exist as glycosides.

Linalool, geraniol, nerol, citronellol and other terpenes, the main aroma compounds, are all stored as glycosides. While bound to sugar they do not evaporate, so you cannot smell them.

When withering changes the cell membranes of the leaf, glycosidase (the enzyme that hydrolyzes glycosides) starts to act on these terpenoid glycosides.

So withering is very important for forming the aroma. Without care at this step, it is hard to bring out the aroma of flowers and fruit.

Many people look at bright green Darjeeling first flush or Taiwanese high mountain oolong and think it is a kind of green tea. It is true that polyphenol oxidase has barely worked on these teas, so the leaves stay green and look like green tea. However, during withering, enzymes such as glycosidase become active, aroma precursors break down, and linalool, geraniol, nerol and citronellol are formed. They look like green tea, but enzymes have fermented the aroma, so they are really fermented teas.

Read the article on why oxidase alone does not explain the aroma of fermented tea, and why the key is the science of withering

Why leafhoppers sucking sap give Darjeeling tea a flavor like honey

Summer Darjeeling (2nd Flush) is known for muscatel flavor, the flavor of ripe muscat grapes. To me, it tastes more of ripe mango than muscat.

Muscat flavors are in Taiwan's Oriental Beauty too. That tea uses only leaves bitten by leafhoppers.

The muscatel flavor of Darjeeling also comes from leafhoppers.

Leafhoppers arrive in large numbers and suck sap from the tender parts of the leaf. Those leaves turn yellow. When only those parts are plucked and processed, the result is that familiar muscatel flavor.

However, leafhoppers are not found everywhere on an estate. They appear only in a very few places.

When leafhoppers suck its sap, the tea leaf tries to resist the insect by making a defensive substance called phytoalexin, which plays a role like that of antibodies in humans.

Phytoalexin contains hotrienol, an aroma precursor. During withering, hydrolytic enzymes break it down into compounds that smell like muscat.

Another secret of Darjeeling tea's muscatel flavor, besides leafhoppers

Leafhoppers are not the only secret of muscatel flavor.

There is also a very small insect called thrips. Leaves bitten by this insect, like those bitten by leafhoppers, turn yellow and develop a bumpy surface.

There is one more secret to good flavor in tea, and it is environmental stress. The harsher the place it grows, the harder the plant works to stay alive, and the more concentrated the leaf becomes. That gives a strong flavor.

Read the article: Another secret of Darjeeling tea's muscatel flavor, besides leafhoppers

The close relationship between altitude and tea quality

A tea estate spreading over a mountain slope in Darjeeling

A tea estate in Darjeeling is one large mountain.

Each estate is vast, covering several hundred hectares, and altitudes vary from a few hundred meters to nearly 2000 meters. For example, Singbulli sits at 360m to 1230m and Risheehat at 760m to 1460m.

In fact, this is because the Darjeeling 1st Flush that comes out early is from low-altitude estates.

At high-altitude estates, the sunlight is strong and photosynthesis is more efficient.

High altitude also means cold nights and thin air, so the plant's respiration (taking in oxygen and giving off carbon dioxide) slows down. The tea then grows very slowly and uses up little of what it made during the day, which makes both taste and flavor rich.

However, heavy fertilizing speeds up growth even at high altitude, and the quality benefit of altitude is cut by half.

To get tea from high-altitude estates, HOJO looks to the middle and late season, and does not go for the first spring plucking.

Read the article on the close relationship between altitude and tea quality

Darjeeling winter tea, rich in flavor and taste

We say autumn (called autumnal in Darjeeling) as if it were one thing, but the autumn harvest starts in September and continues until December.

Tea is an evergreen, like the camellia, so its leaves do not change color or fall. But that is just on the outside. Inside, many changes are taking place ahead of winter. Tea made from these leaves has a very strong, sweet flavor and a deeper taste. Autumn tea also shows the effects of leafhoppers and other insects, so its flavor is very gorgeous.

Read the article on the late harvest of Darjeeling winter tea, rich in flavor and taste

Field report from the estates: organic farming in Darjeeling

I was told the most important concept in organic farming is Live or Leave, and not Live or let Die.

Herbs are used in place of pesticides. They are cut regularly, chopped in a shredder, and soaked in water for nearly two weeks. The water, now holding the herb extract, protects the tea from insects.

Of course, these are not synthetic pesticides, so the insects do not die. They simply leave.

Read the article: Field report from the estates: organic farming in Darjeeling

A new way to enjoy Darjeeling tea: aging

We tend to think the newer the tea, the better, but that is only an assumption. Tea is made by processing, like wine or ham, and with proper aging it can reach a more gorgeous character than new tea has.

Darjeeling and oolong in particular, aged without oxygen, grow sweeter, stronger and deeper in flavor. Taste the tea before and after aging, and the difference is clear.

You may ask how tea can age without oxygen. To answer that, we have to treat oxidation and oxygen as two separate things. Most people think of oxidation as a reaction with oxygen.

In chemistry, however, oxidation covers reactions with oxygen and reactions that lose hydrogen or electrons. So oxidation can happen with no oxygen present. The important thing is that the presence of oxygen completely changes how oxidation happens. With oxygen, more oxygen keeps coming in from outside, many compounds in the leaf oxidize, and the tea deteriorates with a stale smell. Without oxygen, that oxidation does not occur, while reactions that need no oxygen continue slowly inside the leaf.

Even so, vacuum-packed tea is not suitable. With vacuum packing, even the most expensive professional machine is said to leave 1% of the oxygen behind. In fact, this 1% does the damage.

The only way to get to zero oxygen is an oxygen absorber. Only tea packed that way develops a special flavor as it ages.