The document summarizes the basic steps in processing non-orthodox tea: plucking, withering, rolling, fermentation, drying, sorting, tasting, and packaging. It describes the key objectives and processes involved in each step. Plucking is done by hand or machine and affects tea quality. Withering involves moisture removal to prepare leaves for further processing. Fermentation uses oxidation reactions to develop flavor and color. Drying stops enzymatic reactions and produces a stable product. Sorting and tasting separate leaves by grade before final packaging. The detailed explanations provide important context for understanding black tea manufacturing.

1. Tea Manufacturing & Process
For Non-orthodox Tea.
By: Sabbir AhmedShawon.
Food Engineering And Tea TechnologyDepartment.
Shahjalal University of Science & Technology. Sylhet, Bangladesh.

2. Basic Steps of Processing & Manufacturing:
 Withering.
 Rolling.
 Fermentation.
 Drying.
 Shorting.
 Tea Tasting
 Packaging

3. Pluckingcan be done by two ways:
PLUCKING
Hand Plucking
• Standardplucking table is two leaves and a bud.
• Longer the shoot considered to be course plucking.
• High amount of tannin
• High amount of caffeine
• High amount of polyphenol oxidase
• Less amount of moisture.

5.  Mechanized Plucking.
• It done by plucking machine.
• Includes a large beg at the end of the machine.
• Save time and labor cost.
• Tea Quality hampered because of course plucking

8. WITHERING
• Withering means partial removal of moisture of
fresh leaf.
• Leaf consisting (74-80) % moisture and (20-26) %
solidmatters.
• After withering moisture level reduce down to (55-
60) %.
• Helps in smooth operations of the rest
manufacturing processes.

9. Physical Changes In Withering:
• Moisture loss through stomata pore.
• Young leaves wither earlier than the old
leaves.
• (3-4)% of solid substance of dry weight
loss due to respiration
PhysicalWitherCanBeAchievedIn3-4HoursButChemicalWither
Requires12-16Hours.

10. Bio-chemical Changes In Withering :
• Increasepolyphenol oxidase activates.
• Breakdown the chlorophyll and proteins to
aminoacids.
• Increasethe level of organic acid.
• Increasepermeability of cell membrane.
• Oxidation of carbohydrates, fats, & other
soluble component to carbon-di-oxide, water
and energy.

11. Withering system:
• Natural withering: Includes chung or rack withering.
• Controlled withering: Includes drum, tunnel, trough
withering.

12. Withering Trough:
• Invented by the tea planter, Deson in Zaire.
• It made of bricks, concrete, wood or metal. And Consist of
a long trough, single or double hot air flow system.
Working principle:
A fan is provided with the heating arrangement to flow
hot air along the trough. Absorbing this heat, moisture
presents in fresh leaf start being evaporated.

13. The Troughs Are Of Two Types –
• Open trough: In the open type of trough, leaf is spread at a given
thickness and air is blown upwards from the bottom of the
perforatedbed.
• Enclosed trough: In the enclosed troughs the leaf bed is kept in an
enclosed environment by raising the sides of the withering troughs
and using a cover on top of the bed. This is designed to create a
plenum chamber on top of the leaf bed as well. In this case the fan is
always made to blow air only in the forward direction and air can be
made to pass either from top to the bottom or from bottom to the top
with damper and shutter control at the air entry and exit points
respectively without reversing the direction of the fan. The chance of
leaf damage in enclosedtroughis much lower.

16. Field Tests For Perfect Withering:
• When a handful of fresh leaves squeezed and emit, a
carking sound or stems break down indicates
incomplete withering.
• When a handful of fresh leaves squeezed and emit, if
it springs back, it indicates incomplete withering.
• If it retains its shape as a compact ball, it indicates
well withered.

17. Rolling
Rolling is a process to reduce
the leaf size & disrupt the cell
wall and expose their
contents to start the process
of oxidation.

18. The Objectives of Rolling :
• Press out the juice from leaf in such a manner that
leaf does not break up too quickly.
• Rupture the cell walls and mix the chemical
components for subsequent fermentation.
• Make a homogeneous process of oxidative
reaction.
• twist the leaf and give it the desired shape or
appearance .

19. Methods Of Un-orthodox Tea Rolling:
• Lawrie the processor (L.T.P)
• CTC(crush, tear & curl)
• The rotor vane
• The leg cut machine.
• The boruah continuous roller.
As CTC and the rotor vane machine are widely used throughthe world,
we are here gong to show youonly these two type methods.

20. Principle of Working (CTC):
The triple process of Crushing, Tearing and Curling is done by
the teeth on the two rollers moving against each other at
differential speeds. The slower roller rotated with 70rmp and
for the fast one with 700rpm. Preconditioned leaf is fed to the
slow speed roller. The another roller imparts a relative motion
between the surface of two roller with leaf in between. The leaf
comes out though bottom- crushed,tornand curled.

21. CTC(crush,tear& curl)Machine

23. Fermentation.
Is a process of oxidation of
various chemical constitutions of
tea leaf through a series of
chemical reactions.

24. Objectives Of Fermentation:
• Oxidation of polyphenol.
• Formation of Theaflavin and
Thearubigin.
• Development of aroma and flavor.

26. Principal Reactions Process:
The six catechins (a type of polyphenol) present in tea
shoots are.
• Catechin (C),
• Epicatechin (EC),
• Epicatechin gallate(ecg),
• Gallocatechin (GC),
• Epigallocatechin (EGC), and
• Epigallocatechin gallate(EGCG).

27. These catechins are oxidized by Polyphenol
Oxidase(PPO) and form Theaflavin(TF) and
Thearubigin(TG).
Theaflavin is orange red in color and Thearubigin is red
brown in color.
Formation of Theaflavin and Thearubigin ratio is 1:10.

28. Enzyme Dependent Reactions:
These reaction results:
• The formation of theaflavin(TF) and
Thearubigin(TG).
• Development of aroma and flavor
• Breakdown of chlorophyll
• Change in carotenoids, organic acids and
nucleotides.

29. Basic reactions which occur during the formation of
Theaflavins are-
EGC+ EC + O2 = Theaflavin + CO2
EGCG+ EC + O2 = Theaflavin-3 monogallate + CO2
EGC+ ECG + O2 = Theaflavin-3'- monogallate + CO2
EGCG+ ECG+ O2 = Theaflavin3'3' digallate + CO2
TheaflavinMonogallates Are More Brighter And Brisker ThanTheaflavin
And TheaflavinDigallateIs Much More Brighter And Brisker Than
TheaflavinMonogallate

30. Thearubigins (TR) are formed by action of peroxidase (PO) from the same
catechins, but the reaction is much more complex. It is a complex mixture of
carbohydrate, oxidized polyphenols, and nitrogenous compounds. TRs are
also formed fromTFs. The chemistry of thearubigins is highly complex and
their structures have not yet been established. When the TFs start getting
oxidized to TRs, it has deleterious affect on quality. Thus the skill in
carrying out the oxidation leads to formation of a right combination of TFs
and TRs to give brightness, body and colour of black tea, but unless the
epigallates are present in sufficient quantities, the desired TFs cannot be
formed.

31. It includes the interaction of oxidized
polyphenols and sugars withamino
acids, the tanning or enzymes and other
proteins, reduction of the number of
micro-organism.
Non-enzymatic Chemical Reaction:

32. Temperature 27°-29°C (80-84°F)
Adequate supply of oxygen
Time: 40-90 minutes.
Relative humidity: not less than 95%
Hygrometric difference: 1.1°
Process Requirements

33. Methodofoxidation
Conventional
Floor
Rack
Aluminumsheet
Modern
Trolley trough
Drum
Continues fermenting

34. Continues Fermenting System.

35. Drying:
The mainobjectives of drying are:
• To arrest enzymatic reaction as well as oxidation,
• To remove moisture fromtheleaf particles and to
produce a stable product with good keeping quality.
Mechanism of drying:
1.Constant rate period: surface moistureremovedby evaporation.
2. Falling rate period: core water removedby diffusion.

36. Chemistry Of Drying :
In the finalstage of blacktea processing following chemical changes takeplace:
• By the deactivation of enzyme like Polyphenol Oxidase (PPO), Peroxidase
(PO), etc. almost all the biochemical reactions are brought to an end. However,
as the temperature rises to the level for destroying enzymes, the particular
enzymes get activated and faster reaction takes place in the initial stage of
drying. If the temperature is raisedslowly, TR is likely to be formed.
• Chlorophyll is degraded to pheophytin and pheophorbide at elevated
temperature duringdrying contributingtowards the blackness of made tea.
• At elevated temperature, by binding with proteins, Polyphenols make complex
chemicals, whichbringsdown the level of astringency.
• Interaction between carbohydrates with amino acids at elevated temperature
leads to the formationof flavor components.

37. Shorting And Grading.
Removing fiber:
• The fiber extractor machine works on the principleof
static electricity.
• The pic roller in fiber extractor machine acts as a positive
charge and fiber acts as a negative charge, then both
attract each other and fiber is collectedfromthe roller.

38. Name of tea grade and its mesh size in CTC
Grade Name
Mesh Size
Bellow Above
Whole leaf grade
 FOP- Flowery Orange Pekoe - -
 OP- Orange Pekoe - -
Broken grade
 FP -- Flowery Pekoe/Pekoe 8 10
 FBOP- - Flowery Broken Orange
Pekoe
10 12
 BOP- Broken Orange Pekoe 12 16
Fanning Grade
 OF- Orange Fanning 16 20
 FOF- Flowery Orange fanning 20 24
Dust grade
 PD- Pekoe Dust 24 30
 RD- Red Dust 30 40
 SRD/D-Super Red Dust 40 50
 CD- Churam0ni Dust 50 60

39. Tea taster tastes eachgrade on different criteria like
mouthfeeling and type of residue
Tea Tasting
• Physical appearance
• Infused tea leaf
• Taste.

40. Decoction :
About 2 gm of tea per 100 ml of water is weighed into porcelain pots
provided with lids. Water, which has just reached boiling point, is then
poured into the pots as quickly as possible. Speed is necessary at this
stage to ensure that even the last tea for examination receives water,
whichis still boiling.
Tea is allowed to infuse for exactly five or six minutes or
whether exactly 2 gm of tea is addedto each pot provided .

41. Maximum amount of tea should be packed in the
container because oxygen and moisture in the free
space promotes bacterial growth and enzymes are
regenerated affecting the TFs in particular. After filling,
the containers should be closed promptly.
Packaging

42. Forreferences:
1. Tea cultivation: Comprehensive Treatise: N. G. Hajra
2. Tea culture, processing and Marketing: M.J. Mulky
3. Tea Science: D.L. Sana
4. Tea Estate Management: M.L.Rahman

43. THANK YOU