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Tea processing is the method in which the leaves and flushes from Camellia sinensis are
transformed into the dried leaves for brewing tea. The types of tea are distinguished by the
processing they undergo. In its most general form, tea processing involves oxidising the leaves,
stopping the oxidation, forming the tea and drying it. Of these steps, the degree of oxidation
plays a significant role of determining the final flavour of the tea, with curing and leaf breakage
contributing to a lesser amount flavour.
Although each type of tea has different taste, smell, and visual appearance, tea processing for all
tea types consists of a very similar set of methods with only minor variations:
1. Picking: Tea leaves and flushes, which includes a terminal bud and 2 young leaves, are
plucked from Camellia sinensis bushes twice a year during early spring and early summer
or late spring. Autumn or winter pickings of tea flushes are much less common, though
they occur when climate permits. Picking is done by hand when a higher quality tea is
needed, or where labour costs are not prohibitive. Hand-picking is done by pulling the
flush with a snap of the wrist and does not involve twisting or pinching the flush, since
doing the latter reduces the quality of the leaves. Tea flushes and leaves can also be
picked by machine, though there will be more broken leaves and partial flushes. It is also
more difficult to harvest by machine on mountain slopes where tea is often grown.
2. Wilting: The tea leaves will begin to wilt soon after picking, with a gradual onset of
enzymatic oxidation. Wilting is used to remove excess water from the leaves and allows a
very light amount of oxidation. The leaves can be either put under the sun or left in a
cool breezy room to pull moisture out from the leaves. The leaves sometimes lose more
than a quarter of their weight in water during wilting.
3. Bruising: In order to promote and quicken oxidation, the leaves may be bruised by
tumbling in baskets or by being kneaded or rolled-over by heavy wheels. This also
releases some of the leaf juices, which may aid in oxidation and change the taste profile
of the tea.
4. Oxidation: For teas that require oxidation, the leaves are left on their own in a closed
room where they turn progressively darker. In this process the chlorophyll in the leaves
is enzymatically broken down, and its tannins are released or transformed. This process
is referred to as fermentation in the tea industry, although no true fermentation happens
since the process is not driven by microorganisms. The tea producer may choose when
the oxidation should be stopped. For light oolong teas this may be anywhere from 5-40%
oxidation, in darker oolong teas 60-70%, and in black teas 100% oxidation.
5. Kill-green: Kill-green is done to stop the tea leaf oxidation at a desired level. This
process is accomplished by moderately heating tea leaves, thus deactivating their
oxidative enzymes, without destroying the flavour of the tea. Traditionally, the tea leaves
are panned in a wok or steamed, but with advancements in technology, kill-green is
sometimes done by baking or "panning" in a rolling drum. In CTC black teas, kill-green is
done simultaneously with drying.
6. Yellowing: Unique to yellow teas, warm and damp tea leaves from after kill-green are
allowed to be lightly heated in a closed container, which causes the previously green
leaves to yellow.

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7. Shaping:The damp tea leaves are then rolled to be formed into wrinkle strips. This is
typically done by placing the damp leaves in large cloth bags, which are then kneaded by
hand or machine to form the strips. This rolling action also causes some of the sap and
juices inside the leaves to ooze out, which further enhances the taste of the tea. The
strips of tea can then be formed into other shapes, such as being rolled into spirals,
kneaded and rolled into pellets, or tied into balls and other elaborate shapes.
8. Drying: Drying is done to "finish" the tea for sale. This can be done in a myriad of ways
including panning, sunning, air drying, or baking. However, baking is usually the most
common. Great care must be taken to not over-cook the leaves.
9. Curing: While not always required, some teas required additional aging, secondary-
fermentation, or baking to reach their drinking potential. As well, flavored teas are
manufactured by spraying with aromas and flavors or by storing them with their
flavorants.

Without careful moisture and temperature control during its manufacture and life thereafter,
fungi will grow on tea. This form of fungus causes real fermentation that will contaminate the tea
with toxic and sometimes carcinogenic substances and off-flavours, rendering the tea unfit.
Type specific processing
Tea is traditionally classified based on the degree or period of "fermentation" the leaves have
undergone:
White tea
Young leaves (new growth buds) that have undergone no oxidation; the buds may be
shielded from sunlight to prevent formation of chlorophyll. White tea is produced in lesser
quantities than most other styles, and can be correspondingly more expensive than tea
from the same plant processed by other methods. It is less well known in countries
outside of China, though this is changing with increased western interest in organic or
premium teas.
Green tea
The oxidation process is stopped after a minimal amount of oxidation by application of
heat, either with steam, or by dry cooking in hot pans, the traditional Chinese method.
Tea leaves may be left to dry as separate leaves or they may be rolled into small pellets
to make Gunpowder tea. This process is time consuming and is typically done with
pekoes of higher quality. The tea is processed within one to two days of harvesting.
Oolong (Wulong)
Oxidation is stopped somewhere between the standards for green tea and black tea. The
oxidation process takes two to three days. In Chinese, semi-oxidized teas are collectively
grouped as blue tea ( 青 茶 , literally: blue-green tea), while the term "oolong" is used
specifically as a name for certain semi-oxidized teas. [2]
Black tea/Red tea
The tea leaves are allowed to completely oxidize. Black tea is the most common form of
tea in southern Asia (Sri Lanka, India, Pakistan, Bangladesh, etc.) and in the last century
many African countries including Kenya, Burundi, Rwanda, Malawi and Zimbabwe. The

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literal translation of the Chinese word is red tea, which is used by some tea lovers. The
Chinese call it red tea because the actual tea liquid is red. Westerners call it black tea
because the tea leaves used to brew it are usually black. However, red tea may also refer
to rooibos, an increasingly popular South African tisane The oxidation process will take
between two weeks and one month. Black tea is further classified as either orthodox or
as CTC (Crush, Tear, Curl, a production method developed about 1932). Unblended
black teas are also identified by the estate they come from, their year and the flush
(first, second or autumn). Orthodox processed black teas are further graded according to
the post-production leaf quality by the Orange Pekoe system, while CTC teas use a
different grading system.
Post-fermented tea
Teas that undergo a second oxidation, such as Pu-erh, Liu'an, and Liubao, are collectively
referred to as secondary or post-fermentation teas in English. In Chinese they are
categorized as Dark tea or black tea. This is not to be confused with the English term
Black tea, known in Chinese as red tea. Pu-erh, also known as Póu léi (Polee) in
Cantonese is the most common type of post-fermetation tea in the market.
Yellow tea
Either used as a name of special tea processed similarly to green tea, or high-quality tea
served at the Imperial court.
Kukicha
Also called winter tea, kukicha is made from twigs and old leaves pruned from the tea
plant during its dormant season and dry-roasted over a fire. It is popular as a health food
in Japan and in macrobiotic diets.

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Steps in the processing of Tea

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White Tea Processing - The production of white tea is different from green tea. White tea
leaves come from a special varietal tea bush called Narcissus or chaicha bushes. For white tea,
the little buds that form on the plant are covered with silver hairs that give the young leaves a
white appearance. According to the different standards of picking and selecting, white teas can
be classified as Silver Needle, Bai Mu Dan (White Peony), Gongmei (Tribute Eyebrow), and
Shou Mei (Noble, Long Life Eyebrow). All of these white teas are widely produced in China and
are available in America. The highest-quality white teas are Silver Needle and White Peony,
both of which have various grades and are primarily produced in the Fuding and Zhenhe
districts of Fujian, China.
The Process
Silver Needle is carefully hand selected from the tender fleshy sprouts of the "Big
White" or the "Narcissus" tea bush. If the buds are selected with two leaves intact, then the
resulting selection will be made into White Peony tea. The leaves and other material left over
from the selection of Silver Needle and White Peony will be processed into Noble, Long Life
Eyebrow. Gong Mei is made from "chaicha" bushes and is processed slightly differently than
other white teas. Both Gong Mei and Shou Mei are considered lesser forms of white tea
compared to Yin Zhen Bai Hao and Bai Mu Dan.
White Tea leaves are not steamed or pan-fired as is the case in green tea but rather
the leaves are withered, hand selected and sun dried. The special nature of white tea's color,
leaf shape and hair fragrance is mainly created during the withering stage. If mechanical
drying is required the leaves are baked (not fired) at temperatures less that 40’C. Only special
‘two leaves and a bud’ are selected. These leaves must show a very light green almost gray
white color and be covered with velvet peach fuzz down. The ideal is a leaf or two being
wrapped around a newly developing shoot. These shoots are plucked and segregated from the
rest of the leaf being plucked. These leaves are then naturally withered and the painstaking
process on final manual selection occurs. "Three Whites" is the primary requirement of the
fresh tea material. This means the buds, the first leaves and the second leaves must be
covered with tiny white hairs. Be warned that a tea with an abundance of white tips or large
buds is not necessarily a true white tea.
The quality of white tea is greatly dependent on the season of harvesting. The best
white tea is picked in early spring and is subject to numerous requirements. First of all,
picking top-grade white tea is prohibited on rainy days or when the early morning dew is not
dry. It should never be picked when the buds appear purple; when they are damaged by wind,
people, or insects; when they have begun to open; when they are hollow; when they are too
long or too thin; when there is one bud with three to four leaves; and when there is frost on
the ground.
White tea production is greatly dependent on the weather conditions when the tea is
made. Adjustments to the withering stage and the method of bake drying will be determined

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by tea makers as they interpret the effect the weather will have on the withering process.
Temperature and humidity of the environment will dictate the techniques and timing of the
withering and bake drying process. White tea that is withered in conditions that are too hot
will become reddish, while leaves that are withered in conditions that are too cold will become
blackish.
A tea maker's ability to balance solar and indoor withering of white tea is the major
determining factor of quality. There are many nuances of white tea production that are
dependent on the region and climate where the tea is made, but the major stages in the
process are selective picking from specific varietals, withering, careful hand selection, and
bake drying.
Aracha: Crude Tea Processing - Tea leaves are picked 4 times a year from plantations and
classified according to season and other factors. The leaves begin oxidizing as soon as they
are picked.
Tea leaves are picked 4 times a year from plantations and classified according to season and
other factors. The leaves begin oxidizing as soon as they are picked. Japanese green teas are
heat processed (steamed or roasted) while leaves are fresh to prevent oxidation. Leaves are
rolled and pressed for shaping, and moisture is extracted so they can be stored. At this point it
is called Aracha or crude tea.
Aracha Processing Steps:
Fresh Leaves
Two or three leaves and a bud are picked for sencha while more mature leaves are
picked later for bancha. Fresh tealeaves are still alive and breathing which creates heat and
causes oxidation.
Air Stirring and Moisturizing
Fresh tealeaves begin fermenting and oxidizing as soon as they are picked. The leaves
must be placed in a high humidity environment in order to maintain quality. A moist low
temperature is maintained to keep the leaves fresh
Steaming
Steaming the leaves evenly with non-pressurized steam stops the oxidation process and
removes the grassy smell, maintaining a rich green color. This process determines the color
and quality of green teas. The length of steaming time determines a tea's taste, aroma and
color of the liquor. Extra special steaming produces a deep murky green liquid but the color of
the tealeaves beccome bright and the level of astringency and aroma are reduced.
- Light steamed sencha requires 20-30 seconds of    steaming
-  Regular-steamed sencha requires 30-40 seconds
-  Heavily-steamed sencha requires 40-60 seconds
-  Special-steamed sencha requires more than 90    seconds
-  Extra special-steaming (which our producer prefers)    requires 120 seconds.

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Cooling
Tea leaves loose their fresh aroma and color if they are steamed and left at a high
temperature. They must be cooled down quickly and evenly to room temeprature through the
use of cool air.
Scattering
After cooling, tealeaves are pressure rolled while dry and hot air is used. Removing moisture
from the leaf's surface improves color and aroma. This also makes the drying process more
efficient and shortens the primary drying step that follows.
Primary Drying
After scattering, tealeaves are pressed and rolled and hot air is used on the dry leaves. This
process softens the leaves and reduces the level of moisture further.
Rolling
The tealeaves are all gathered together and pressed and rolled without heat. Leaves not rolled
enough earlier in the process are rolled further. This process levels off the moisture content of
the leaves and destroys the tea tissue. This allows the substances within the tea to easily
emerge when brewed.
Secondary Drying
Leaves are pressed and rolled while dry air is pumped in. Prior to this step the leaves are still
wrinkled, irregularly shaped and still contain a relatively high moisture content. This process
unravels the tea, shapes it into a roll, and dries the leaves so that they are easily arranged in
the next step.
Final Rolling
Moisture in the leaves is extracted, enhancing dryness. The leaves are then rolled in one
direction into a long thin shape peculiar to Japanese green tea.
Drying
After final rolling, tealeaves still contain about 10%-13% moisture. This hot air drying process
reduces the moisture level to 5% for long term preservation and increases the flavor of the
tea
Shiagecha (Refined Tea) Processing - During this refining process, a quality of tea is
determined. It has developed a unique pan firing process to achieve maximum taste, aroma,
color and nutritional benefit.
The tea refining process is designed to accomplish the following objectives:
- To create uniform leaf shape and remove powder,   stems, sticks and mature leaves.
- To reduce the level of moisture making the tea    suitable for consumer storage.
- To balance the flavors through leaf roasting    according to consumer preferences.
- To increase the quality and thus the value value of    the final tea product.
The refining process includes the following procedures as teas are blended by flavor
preferences:
- Fire drying

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- Shaping by sifting and cutting

- Selecting by air and electricity
From here the processes get rather complicated and vary from factory to factory but the key
step of pan firing can be catagorized into two styles: Pre-Firing and Post-Firing.
Pre-Firing
All the crude tea is fired together, followed by catagorizing and shaping. This is an efficient
method for mass production.
Post-Firing
Our producer favors this more labor intensive method because it produces a more delicious
and nutritious product of distinguishable higher quality. Crude tea is first shaped and sorted by
shape and weight and then fired by the tea category it falls into. This method utilizes low heat
for portions containing green colored leaves and applies high heat to the portions that are
more flavorful. This uneven form of heating by leaf category brings out the best combination
of color, taste and aroma. Our producer has five leaf classifications for the purpose of firing:

Leaf Description  Process Advantage

Thick & Heavy firing aroma & taste
Thin, Long & Heavy firing taste, color & shape
Small & Heavy firing taste aroma & brewed color
Small & Light drying Brewed color
Other Light drying Brewed color

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Tea Leaf Grading

Grading tea leaves is complicated and is done differently in different countries. The most
extensive grading is found in black teas, followed by green teas. The most basic or the first
grade of black tea produced is called OP or Orange Pekoe (say peck-oh). Pekoe is derived from
the Chinese word “pak-Ho” meaning “hair” or “down” relating to the light white down on the
bud leaves. One explanation for the “Orange” half of the name is that the Chinese sometimes
used Orange blossoms to flavor these leaves. Another suggests that it is a remaining
reference to the Netherlands House of Orange, a powerful entity in the early days of tea
trading. Either way, today Orange Pekoe describes leaves, specifically the best, most tender
leaves plucked from the tips of the plant’s young shoots. Black tea is classified into four
different categories: WHOLE LEAF, BROKEN LEAF, FANNINGS and DUST.
These prized leaves get graded as follows during the manufacturing process:
WHOLE LEAF
1) FLOWERY ORANGE PEKOE (FOP) - Consists of fine, tender, young leaves rolled with a
certain proportion of “tips.” These tips, being the very ends of the bud’s leaves, constitute a
guarantee of quality.
2) GOLDEN FLOWERY ORANGE PEKOE (GFOP) - FOP with “golden tips” (fine tips of the golden
yellow bud’s leaves)
3) TIPPY GOLDEN FLOWERY ORANGE PEKOE (TGFOP) - FOP with lots of “golden tips”
4) FINEST TIPPY GOLDEN FLOWERY ORANGE PEKOE (FTGFOP) - Exceptional quality FOP
5) SPECIAL FINEST TIPPY GOLDEN FLOWERY ORANGE PEKOE (SFTGFOP) - The very best FOP
with a large proportion of leaves having golden “tips” of new leaf buds---a guarantee of very,
very high quality
6) ORANGE PEKOE (OP) - Long, pointed leaves (larger than FOP) rolled lengthwise. Harvested
when the terminal buds open into leaf. Orange Pekoe rarely contains “tips.”
7) PEKOE (P) - Shorter, less fine leaves without “tips”.
8) FLOWERY PEKOE (FP) - Leaves specially rolled into ball shape.
9) PEKOE SOUCHONG (PS) - Shorter, coarser leaves.
10) SOUCHONG (S) - Large leaves rolled lengthwise. Often used for China smoked teas.
EXPERTS ALSO ADD “1” TO DENOTE TOP QUALITY AFTER A LEAF DESIGNATION; FOR
EXAMPLE: F.T.G.F.O.P. 1, O.P. 1, S 1 etc.
BROKEN LEAF
BROKEN ORANGE PEKOE (BOP)
GOLDEN BROKEN ORANGE PEKOE (GBOP)
FLOWERY BROKEN ORANGE PEKOE (FBOP)
TIPPY GOLDEN BROKEN ORANGE PEKOE (TGBOP)
GOLDEN FLOWERY BROKEN ORANGE PEKOE (GFBOP)
TIPPY GOLDEN FLOWERY BROKEN ORANGE PEKOE (TGFBOP)
FANNINGS
Made from smaller, flat pieces of broken orange pekoe and used to make quick-brewing,
strongly flavored, robust teas with good color.
BROKEN ORANGE PEKOE FANNINGS (BOPF)
DUST
Tiny bits of broken leaf used to brew strong tea quickly, popular for tea bags.
BROKEN ORANGE PEKOE DUST (BOPD)

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PEKOE DUST (PD)

RED DUST (RD)
SUPER RED DUST (SRD)
FINE DUST (FD)
SUPER FINE DUST (SFD)
GOLDEN DUST (GD)
Temperature
Optimum : 24'C – 29’C
Factors affecting temperature :  
i)   leaf temperatures at the end of green leaf processing,  
            ii) thickness of spread  
            iii) temperature of air in fermenting room.
 Humidity  
Optimum : 1’C – 1.5 ‘C Hygrometric Difference 
Any larger H.D. requires humidification of the room. 
Normal method : mist chambers or spray units.
Spread
On floor, sheet or table  
Thickness Orthodox CTC
2 cm thick, 1 Kg leaf takes 0.18m 2
0.12m2
3 cm thick, 1 Kg leaf takes 0.12m 2
0.08m2
4 cm thick, 1 Kg leaf takes 0.08 0.06..  
5 cm thick, 1 Kg leaf takes 0.09 0.05..
 Approx. space requirements Orthodox   Roll/CTC RV/CTC
For 1000 Kg throughput per hr 600 225
Air for floor fermentation
10-12 changes of air per hour. lf natural ventilation does not as that all air in the room is
renewed every 5-6 minutes, fan assistance may have to be given, air speed to be kept as low
as possible.
Fermenting Troughs
Pressure in trough : 2-5 cm water gauge depending on depth of leaf and Particle size.
Hygrometric difference : dry air blackens leaf.
For a 1000 Kg G.L. throughput per hr.
C.T.C. 100 gamlas 
                                    3 roll Orthodox 150 gamlas 
                                    2 roll Orthodox 160 gamlas
Fermenting Machine
Size aid capacity varies from manufacturer to manufacturer. Dimensions Of 17m x 4m x 3.5m
would suffice to Supply two 1.8 m dryers.

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