This experiment is to determine and compare the caffeine contents in the caffeinated drinks that we can found in our market. We are conducting the experiment regarding the chemical content in food including beverages. Hence we choose to set up our experiment to find out the caffeinated drink that are available and legal in our country. We are interested in the alkaloid --- caffeine (C8H10N4O2) which is very common substance in many drinks, such as coffee, tea, Coca-Cola etc. Adults or even students will drink a cup of coffee to temporarily restoring alertness and warding off drowsiness. However, we construct the question by setting that how much caffeine really contained in these drinks? How can we determine the amount of caffeine in coffee? The following project will investigate the chemical test for caffeine. At first, we extract caffeine from coffee. Then we need to prove that the extraction contain caffeine. Finally we try to find out the amount of caffeine in coffee. All the tests we investigate can be done in school laboratory, and pure caffeine is bought for verifying and investigating these chemical tests. We hope that these tests can be further developed in order to become more popular, more efficient, lower the cost and less pollute to environment.

1. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
STPM 2016
REPORT OF CHEMISTRY
PROJECT WORK 962/4
SMJK SAM TET (U6B2)
Extraction of Caffeine
NAME IC NO INDEX
Kelvin Tan Kai Min 97032908-5175 SA2011/1125
Chooi Wen Han 970826-08-6013 SA2011/1121
Chooi Kai Sing 970903-38-5435 SA2011/1120
Chan Yong Li 970819-38-5285 SA2011/1118

2. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
Content
Abstract
Content
1.0 Introduction.........................................................................................( 1 )
1.1 General Information............................................................................( 1 )
1.2 Literature Review...............................................................................( 2 )
1.3 Objective.............................................................................................( 3 )
1.4 Problem Statement..............................................................................( 3 )
2.0Methodology........................................................................................( 4 )
2.1 Apparatus and Materials...........................................................( 4 )
2.2 Procedure..................................................................................( 5 )
3.0 Observation and Result.......................................................................( 6 )
3.1 Observation...............................................................................( 7 )
3.2 Result.........................................................................................( 8 )
4.0 Discussion............................................................................................( 9 )
5.0 Conclusion............................................................................................( 10 )
6.0 Reference..............................................................................................( 11 )

3. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
ABSTRACT
This experiment is to determine and compare the caffeine contents in the caffeinated drinks
that we can found in our market. We are conducting the experiment regarding the chemical
content in food including beverages. Hence we choose to set up our experiment to find out the
caffeinated drink that are available and legal in our country. We are interested in the alkaloid -
-- caffeine (C8H10N4O2) which is very common substance in many drinks, such as coffee, tea,
Coca-Cola etc. Adults or even students will drink a cup of coffee to temporarily restoring
alertness and warding off drowsiness. However, we construct the question by setting that how
much caffeine really contained in these drinks? How can we determine the amount of caffeine
in coffee? The following project will investigate the chemical test for caffeine. At first, we
extract caffeine from coffee. Then we need to prove that the extraction contain caffeine. Finally
we try to find out the amount of caffeine in coffee. All the tests we investigate can be done in
school laboratory, and pure caffeine is bought for verifying and investigating these chemical
tests. We hope that these tests can be further developed in order to become more popular, more
efficient, lower the cost and less pollute to environment.
I.

4. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
INTRODUCTION
1.1 GENERAL INFORMATION
Caffeine
Caffeine occurs naturally in tea leaves and coffee beans. Cocoa beans, used to produce
chocolate, contain a compound that is nearly identical in structure to caffeine. Caffeine is also
added to many types of soda and energy drinks. Caffeine is a white solid material at room
temperature. It is classified as an alkaloid—a nitrogen-containing basic (as opposed to acidic)
compound that is obtained from plants and has physiological effects in the body. Caffeine is a
stimulant and mildly addictive. Withdrawal symptoms may include headache and irritability.
There is no conclusive evidence that caffeine causes cancer or heart disease. However, animal
studies suggest it may be a weak teratogen (an agent that causes birth defects in an embryo or
fetus), so pregnant women are advised to limit their intake of caffeinated beverages.
Structure of caffeine:
1

5. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
1.2 LITERATURE REVIEW
Extraction is a separation technique that depends on differential solubility in a chosen solvent.
Extraction is most appropriately applied when a desired compound exists in a matrix that
consists of several other components. These other components can be viewed as contaminants
in this context. This matrix can either be solid or liquid. In the most general sense, the matrix
is exposed to a solvent which is chosen because of its selectivity in terms of solubility for the
desired compound. The solvent must also be relatively volatile and inert. Why? After an
appropriate period of interaction, the newly formed solution is removed, leaving the balance of
the matrix behind. The solvent is then separated from the desired compound, often by
distillation or rotary evaporation. Sometimes extraction is used to specifically remove
contaminant molecules. In this circumstance, the extraction is called a "wash" though all the
same principles apply.
If the matrix is solid state, the process is called solid/liquid extraction. For example, you carry
out a solid/liquid extraction every time you make a cup of coffee or tea at home. The coffee or
tea constitutes the solid matrix and the hot water serves to remove molecules from the matrix.
Making such a hot beverage is not particularly selective since many different molecules are
removed from the solid matrix.
2

6. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
1.3 OBJECTIVE
1. To analyst the total ratio of caffeine contain in caffeine drinks.
2. Compare the caffeine contents in both Arabica coffee bean and BOH tea.
1.4 PROBLEM STATEMENT
Coffee bean and Tea leaves were used in this experiment. So, which caffeinated drink contains
a higher amount of caffeine?
3

7. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
2.0 METHODOLOGY
In this experiment our main objective is to compare the quantity of caffeine between a tea bag
and coffee beans. First, we try to extract caffeine from coffee by a suitable method. Then, by
using chemical tests to analysis the amount of caffeine in coffee and extract.
Last, we want to validate the efficiency of the extraction method.
2.1 APPARATUS AND MATERIAL
Apparatus: Separating funnel, electrical balance, Beaker , Burette , Volumetric Flask ,
measuring cylinder , Bunsen Burner , Suction pump
Material: Distilled water (250ml), Dichloromethane (1000ml) , Coffee Bean(30g) , Tea
Bags(30g)
4

8. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
2.2 PROCEDURE
(A)PREPARING OF RAW COFFEE SOLUTION
1. 30g of coffee beans were grind and weighted.
2. Add 60ml of distilled water and boil it and brew it left to evaporated at 80ml of solution.
3. The coffee solution is brewed according to the package instructions.
4. The solution is then left to cool to room temperature.
(B) SOLVENT EXTRACTION
1. Rinse all the apparatus in dichloromethane
2. Transfer the raw coffee solution to a separating funnel
3. Add 20ml of dichloromethane.
4. Shake the separating funnel gently and open one up the opening every 5seconds interval
without pouring the solution only to release build up pressure produced by the gas
released.
5. Place the separating funnel at rest for 1 minute to allow the density gradient of coffee
solution and dichloromethane to be formed.
6. Open the opening bottom of the separating funnel to flow out the dichloromethane
without allowing any coffee solution to be poured out into the conical flask.
7. The separated dichloromethane is then boiled in the conical flask to evaporate the
solution until precipitate is formed.
8. The precipitate is scraped out on a piece of filter paper and weighted.
9. The whole process is repeated using a differ material of Tea bags.
5

9. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
3.0 OBSERVATION AND RESULT
3.1 OBSERVATION
We have been conducting the experiment for few hours. We have recorded the changes as
well as the result during the experiment. Before we are able to measure the mass of the
extracted caffeine, there are few observations that we have recorded. When the coffee and
tea is boiled and ready after the boiling process, we have to transfer them into suction
pump to filter the coffee residues and tea leaves to separate them totally from the
solution. We have observe that the solution we obtain after the filter process having less
volume compare to the volume before we pour the caffeinated solution into suction
pump. Then, we added the dichloromethane into the caffeinated solution (coffee and tea)
separately. We shake the mixture gently and thoroughly in the separating funnel. We
observed that there are two layers form right after we shake the solution. On the top layer
it appears as brown colour which is same as the coffee solution and tea solution. The
bottom layer appears as a clear and transparent solution. Then, we have to boil the
solution containing dichloromethane together with caffeine content until the solution boil
and only precipitate left in the conical flask. Within a minute, we are able to observe the
solution has dried out and the precipitates are formed at the bottom of the conical flask.
6

10. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
3.2 RESULT
Volume of raw coffee/Tea leaves solution used in each extraction =150cm3
Extraction of coffee powder Extraction of Tea Leaves
Mass of conical flask(g) 48.5210 48.5176
Mass of conical flask with
extracted Crude Caffeine(g)
48.6110 48.5236
Mass of caffeine extracted (g) 0.09 0.06
Coffee Bean Tea Bag
Mass of material used (g) 30.00 30.00
Mass of caffeine extracted (g) 0.09 0.06
Percentage of caffeine contain
(%)
0.3 0.2
7

11. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
8
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
Coffee Tea
Extracted Caffeine (g)
Extracted Caffeine (g)
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
Coffee Tea
Percentage of Caffeine Contain (%)
Percentage of Caffeine Contain
(%)

12. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
4.0 DISCUSSION
From the solvent extraction test, the amount of caffeine extracted from coffee powder is
weighted with 0.09g while the caffeine from Tea bags were weight 0.06.This shows a 0.03
difference between coffee powder and Tea Bags. Besides that , this experiment is carried out
using the same amount of grams of coffee powder and Tea bags to carry out a fair and equal
result. As we can see from the result of this experiment, 30g of coffee beans contain 0.3% of
caffeine which have a higher caffeine contents than 30g of tea bag that only contain 0.2% of
caffeine. From the beginning, we are aim to compare the caffeine contents in both coffee bean
and tea bag. During the experiment, we did not manage to open up or destroy the tea bag and
only use the tea leave inside the tea bag is because consumers will not having the habit of open
up the tea bag during their daily life. Hence, when we are measuring the caffeine contents in
tea leave which pack inside the tea bag will be more suitable as that will be the caffeine content
that consumer will obtain from drinking BOH tea. Compare to coffee bean, we are able to grind
the coffee beans as consumer normally drinking their coffee with grinded coffee. Thus, it will
be more realistic to conduct this experiment when we grind the coffee bean to obtain the
caffeine ratio in it. These are both common caffeinated drink that we can buy from the market
in Malaysia. As both coffee and tea are able to boost up our brain and allow us to be mentally
more awake for our work, it is necessary for us to understand which caffeinated drink should
we choose in order to have a higher efficiency in improving our mind to avoid tiredness.
9

13. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
5.0 CONCLUSION
After the above test, we confirmed that the about solvent extraction is a practical
experimental procedure for extraction in school laboratory. The result of this experiment may
not 100% perfectly correct same as the exact amount of caffeine contain in both coffee and tea,
but by conducting this experiment, we may able to describe the result that we have gained is
an effort for further discover about the caffeine content in caffeinated drink. However
dichloromethane which is used to extract caffeine from their original compounds it is a
corrosive solution to be used and during the experiment procedure it should be handle with
care.
Therefore, it can be concluded that in nature coffee beans have a higher ratio of caffeine
comparing to tea leaves.
10

14. 2016 U6B2 Chemistry Coursework- CWH, CKS, CYL, TKM
6.0 Reference
Ho Chun Lok, Kwok Man Kit, Chan Kam Tung, Tse Sze Ho. (2013). Chemical Test for Caffeine.
Hong Kong : Hong Kong Chemistry Olympiad for Secondary Schools .
Smith, S. W. (2015). Caffeine. Retrieved from Chemistry Explained:
http://www.chemistryexplained.com/Bo-Ce/Caffeine.html
Bedel, B. (2012). Extraction of Caffeine from Tea Leaves. LabArchives.
Trimble, J. (2014). Isolation of Caffeine from Tea Leaves. Dinity.
Postu, A. (2013). Isolation of Caffeine from Tea Leaves via Acid-Base Liquid-Liquid Extraction.
11