This document describes a chemistry project that compares the water soluble polyphenol content in different tea samples. The project involves weighing tea bags before and after steeping in hot water to determine the weight loss and percentage of water soluble components. The results will show which tea sample has the highest polyphenol content and best flavor.

1. UDIYAKALA KABIRDHAM
TOPIC-LIGHT EMMITING DIODE
Submited By Guided By
Nohar Das Tandan Mr. Aditya
Bera
Roll No. (P.G.T.
PHYSICS)

3. This is to certify that Nohar Das Tandan of class 12th
has completed his project in the subject of Chemistry
as required according to the syllabus as prescribed by
the central board of secondary education (CBSE) and
the guidance of Mr. S, K, Mishra (P.G.T. Chemistry)
for the academic session 2018-2019.

4. ACKNOWLEDGEMENT:
My sincere thanks to our chemistry teachers
Mr.S.K. Mishra for providing me all facilities
required for the completion of this project and
who supported me with gentle co-operation and
great patience.
I would also like to express my gratitude to our
lab assistant Mr. Ashok for his support during
making the project.
Nohar Das Tandan Class 12 th ‘A’

5. INDEX:
1. AIM
2. INTRODUCTION
3. REQUIREMENT
4. THEORY
5. PROCEDURE
6. OBSERVATION
7. RESULT
8. PRECAUTION
9. BIBLIOGRAPHY

6. AIM:
To compare the water soluble polyphone
(catechin) content in the various samples
of tea leaves.

7. INTRODUCTION:
India is a large exporter of tea which is a crash crop.
Tea is made from the young leaves and unopened buds
of the tea plants camellia. The use of an infusion of
dried tea leaves as a beverage has it origin since very
ancient times. It was first cultivated in china.
Tea leaf is rich in alkaloid caffeine which constitutes as
much as 4% of the dry matter in the young leaf. It is the
main active ingredient of tea which acts as a stimulant.
Besides caffeine, tea leaves contain tannin and
colouring matter polyphenolic compounds and some
flavouring agents. We can check the presence of all
these substances and their relative amounts through
sample experiments.

8. FACTORS AFFECTING THE QUALITY
OF TEA:-
The quality of tea depends on the climate and soil.
Climate: It is the deciding factor as to which variety of tea can be
grown to the best advantage. Change in the climate in the climate
affects the quality and flavor of tea and influences the time of
maximum seed fall. The tea plants best grow in the season of
monsoon land of South East Asia where cool whether if fairly dry
with a market fall in temperature. Frost kills the plants if the sum
reaches the affected area early in the morning before the leaf has
hard time to warm up. To prevent this tea plants are grown under
the trees.
Soil: Tea plants best grow on light loamy soil. However it can be
grown on all types of soil. Potash manure is very good. Nitrogenous
manures whether in organic form or chemical form have adverse
effect on the quality of the tea. Since soils contain such readily
available Aluminum and Magnese which the tea bush consumes
and stores in relatively large amounts, it is the need for these
elements that necessitates an acid soil for the growth of tea.

9. TYPES OF TEA:
TEA IN India is of two types:-
1. The Chinery type tea grows in and around Darjeeling
and yields a rich flavor.
2. The Assam type tea grows in the plants of Assam and
West Bengal and yields strong and bright liquored tea.
3. Aroma(smell) of tea: six hours after the leaf has been
plucked, the rapid development of asparagine’s takes place,
irrespective of whether physical withering has begun or not.
Most of the development of aroma takes place during
fermentation and reaches its optium stage in about 3 and half
hours. The main constituents responsible for aroma are:
>Caffeine
>Polyphenol
>amino acid
>Magnese and other inorganic materials

10. REQUIREMENT:
1. Beaker
2. Conical Flask
3. Funnels
4. Heating Arrangement
5. Tea bags of different brands of tea

11. PRINCIPLE:
Water soluble polyphenol are present up to
30%.They are very much soluble in water largely
responsible for the aroma (smell), color and
quality of tea samples.

12. THEORY:
Tea contains up to 30% of the water soluble
polyphenol (catechin). These are largely soluble in
responsible for the extent of these compounds in
a given sample, the tea leaves are immersed in
hot water for equal time and the loss in the
weight of tea leaves is determined.

13. PROCEDURE:
1. Weigh exactly 5g of the different samples of
tea and place them in tea bags.
2. Take three or four conical flasks and put 100ml
of hot water to each of them.
3. Put tea bags of different samples of tea in the
different conical flasks. After 10 minutes remove
the bags and dry them by placing in an oven.
4. When tea bags become dry, reweight them.
5. Note the flavor of the tea solution obtained.

14. OBSERVATION:
s.no Brand Initial Final Loss of % of water
Name Weight Weight weight Soluble
of Tea [X g] [Y g] Component=
Y/X
1.
2.
3.
4.

15. RESULT:
The polyphenol content is more in ……………………….
The polyphenol content is more in the tea which
gives the better flavor.

16. PRECAUTIONS:
1. Students should wear lab coat.
2. Handle apparatus with care.
3. Do not touch beakers while heating.
4. Do not use large amount of substance.
4. Never taste anything.
5. Wash your hands before leaving the lab.

17. BIBLIOGRAPHY:
1. WIKIPEDIA.COM
2. GOOGLE SEARCH ENGINE
3.CHEMISTRY COMPREHENSIVE MANUAL
OF CLASS XII