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EXTRACTION OF CAFFEINE FROM COFFEE
AND TEA
DESIGN PROJECT-2 REPORT
Submitted by
Roshin Robinson (20108001)
Mani Sharma P (20108007)
Vikash SR (20108010)
Sasthiri K (20108020)
In partial fulfilment for the award of the degree
Of
BACHELOR OF TECHNOLOGY
In
CHEMICAL ENGINEERING
APR 2022
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BONAFIDE CERTIFICATE
Certified that this project report “EXTRACTION OF CAFFEINE FROM COFFEE AND
TEA” Is the bonafide work of Roshin Robinson (20108001), Mani Sharma P (20108007),
Vikash SR (20108010), Sasthiri K (20108020) who carried out the project work (design
projectCHB441) under my supervision.
HEAD OF THE DEPARTMENT SUPERVISOR
Dr. B. VIVEKANANDAN Dr. A. SARAVANAN
Associate Professor Associate Professor
Hindustan Institute of Hindustan Institute of
Technology & Science Technology & Science
Padur, Chennai Padur, Chennai
The Design Project Viva-Voce examination is held on:
…………………………
INTERNAL EXAMINER EXTERNAL EXAMINER
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ACKNOWLEDGEMENT
At the outset we would like to extend our sincere gratitude to Dr. (Mrs.)
ELIZABETH VERGHESE, Chancellor of Hindustan Institute of Technology
and Science for her endeavour in educating us in her esteemed institute which has
helped us work towards our goal. We also express our sincere thanks to Dr. S.N.
SRIDHARA Vice Chancellor of Hindustan Institute of Technology and Science
and to Mr. ASHOK VERGHESE, Director of Hindustan Institute of
Technology and Science. I would also like to thank Dr. B VIVEKANANDAN,
HOD of the department of chemical engineering for giving us this opportunity. I
would like to extend my gratitude to Dr. A. SARAVANAN, Associate Professor,
Department of chemical engineering, for constantly guiding us throughout our
mini project. I would then like to thank our parents for supporting us both
mentally and financially and also for providing us with all the necessary stuff.
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ABSTRACT
Caffeine(3,7-Dihydro-1,3,7-trimethyl-1H-purine-2,6-dione) is a widespread
naturally occurring xanthine derivative found in a variety of plants but commonly
found in coffee beans and tea leaves. Caffeine containing products have been
consumed for hundreds of years for their taste, aroma and CNS stimulating
properties. We estimated the amount of caffeine present in tea and coffee, which
people consume regularly. We extracted caffeine from theseusing ‘liquid-liquid
separation’ method. As an extracting solvent, we have used chloroform in which
caffeine is highly soluble than in any other solvent. Thereafter chloroform from
extract was evaporated until only white crystals remained, which were considered
to be pure Caffeine.
Keywords: Caffeine, Tea, CNS, chloroform.
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TABLE OF CONTENTS
S.NO
CONTENT
PAGE NO.
1
INTRODUCTION
6
2
LITERATURE REVIEW
11
3
MATERIALS AND METHOD
13
4
RESULT AND DISCUSSION
18
5
CONCLUSION
20
6
REFERENCES
21
6
I. INTRODUCTION:
Tea and coffee are the most popular beverages for centuries, primarily due to their
aroma, pleasant taste and stimulant effects. Caffeine is an odourless, slightly
bitter, bioactive heterocyclic amine present in more than 60 plants. It is found
mostly in beverages such as coffee or tea and in some chocolates. A number of
products used as the counter pain relievers, headache remedies and antihistamines
also contain Caffeine. In recent years, caffeine received increasing attention in
food and pharmaceutical industries, due to its pharmacological properties which
comprise stimulation of the central nervous system, peripheral vasoconstriction,
relaxation of the smooth muscle and myocardial stimulation. The caffeine is still
facing many controversies and misconceptions like its intake could result in
enhanced risks of caffeine addiction, cancer, miscarriages, breast diseases,
osteoporosis and hypertension etc. Caffeine is one of the most thoroughly
investigated ingredient in the human food.
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Caffeine has been used as a medicinal and recreational drug since before recorded
history, by consumption of caffeine bearing plants. However, the discovery of the
chemical did not occur until a young physician called Friedlieb Ferdinand Runge
isolated and purified the white crystalline substance in 1819 as result of encounter
with 70-year-old Johann Wolfgang von Goethe.
Caffeine is thought to act on the brain by blocking adenosine receptors.
Adenosine, when bound to receptors of nerve cells, slows down nerve cell
activity; this happens, among other times, during sleep. The Caffeine molecule,
being similar to Adenosine, binds to the same receptors but doesn't cause the cells
to slow down; instead, the Caffeine blocks the receptors and thereby Adenosine
action. The resulting increased nerve activity causes the release of the hormone
Epinephrine, which in turn leads to several effects such as higher heart rate,
increased blood pressure, increased blood flow to muscles, decreased blood flow
to the skin and inner organs, and release of glucose by the liver.
Caffeine acts as a stimulant. It stimulates the heart, respiration, the central
nervous system, and is a diuretic. Its use can cause nervousness, insomnia and
headaches. It is physically addictive. A person who drinks as few as 4 cups of
coffee a day and who attempts to stop “cold turkey” may experience headache,
insomnia, and possibly nausea as the result of withdrawal.
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It is generally agreed that there is little risk of harm when a person consumes less
than 300 mg of caffeine a day1,2. However at times of anxiety or stress, or during
pregnancy, the FSA recommends consumption of less than 200 mg a day3. While
there are no regulatory requirements to control or label food products with their
caffeine content, numerous studies have been carried out to determine the typical
caffeine content of commonly consumed beverages.
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1.1 PHYSICAL AND CHEMICAL PROPERTIES
Caffeine is sparingly soluble in most polar solvents but is highly soluble in less
polar solvents. The melting point is 234°C-239°C and the chemical formula is C8
H10N4 O2. It is an intensely bitter, white powder in its pure state. Caffeine is an
alkaloid of the methylxanthine family, which also includes the similar compounds
theophylline and theobromine.
Fig 1 Structure of a caffeine molecule
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1.2 APPLICATION OF CAFFEINE IN MEDICAL INDUSTRY
Caffeine which is found in tea and coffee imparts bitterness and also acts as a
flavour constituent. It is a mild nervous stimulant towards drowsiness and fatigue.
In this respect, is used by athletes to enhance performance since it mobilizes fats
from stores a process that normally does not become maximal until intense
activity is underway. Caffeine is used as a drug on the basis of its effect on
respiratory, cardiovascular and the central nervous system. It is included with
aspirin in some preparations for treatment of headaches as it decreases cerebral
eye blood flow. Caffeine is administered in the treatment of mild respiratory
depression caused by central nervous system depressants such as narcotic.
Caffeine may also be used in the treatment of acute circulatory failure. In either
beverage or in non-prescription tablet form, it may be used to relieve fatigue since
it increases the amount of urine flow. In fact, there are about 2000 non-
prescription and about 1000 prescription drugs containing caffeine.
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II. LITERATURE REVIEW:
Friedrich Ferdinand Runge etal. Isolated relatively pure caffeine for
the first time. In 1827, Oudry isolated "theine" from tea, but it was later
proved by Mulder and Jobat that theine was the same as caffeine.
The structure of caffeine was elucidated near the end of the 19th century
by Hermann Emil Fischer, who was also the first to achieve its total
synthesis. This was part of the work for which Fischer was awarded the
Nobel Prize in 1902.
Clementz and Dailey (1988) etal. determined Pure caffeine occurs
as odourless, white, fleecy masses, glistening needles of powder. Its
molecular weight is 194.19 g/gmol, melting point is 236, point at which
caffeine sublimes is 178, at atmospheric pressure, pH is 6.9 (1% solution),
specific gravity is 1.2, volatility is 0.5 %, vapour pressure is 760 mm Hg at
178, solubility in water is 2.17 g per 100 mL water at 25, and vapour
density is 6.7.
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Gebely, Mumin (2006) etal. reported that; Every time we drink tea,
coffee, cocoa, chocolate or cola, we are giving our body a hit of caffeine.
Alcohol and nicotine, along with caffeine are the three most widely used
mood-affecting drugs in the world. The effects of caffeine on human being
depend on concentrations. Consuming high dosage of this compound
causes various physiological and psychological effects which include
stimulation of the central nervous system.
Belay (2011) etal. reported that caffeine has a tendency of rapidly
and completely absorbed from gastrointestinal tract within very short
period of time and get distributed in the body. It is not removed from the
circulation until metabolized initially into paraxanthine and thyobromine
then into derivative of uric acid and diaminourcil, which is eventually
removed from the circulation. It is reported that, the plasma half-life of
caffeine in man, that is; the time required for its level to be diminished by
50% via biotransformation and excretion is 5 to 6 hours.
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III. MATERIALS AND METHOD
3.1 MATERIALS REQUIRED
LAB APPARATUS:
500 mL Beaker,250 mL Erlenmeyer flask, Funnel, Distilled Water,
separating funnel, Separatory funnel stand, stirring rod, Whatman filter
paper, Watch glass.
REAGENTS AND MATERIALS:
➢ Tea Bags(or) Coffee bags
➢ Sodium Carbonate (Na
2
Co
3
)
➢ Dichloromethane (Ch
2
Cl
2
)
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3.2 Preparation of Sample
7 grams, of tea (or) coffee were taken in 150 ml of distilled water and 5g of
sodium carbonate is added. The solution was then heated and was kept at 100C
for 15 min. Then, the solution was cooled and filtered using Whatman filter paper.
Fig 2 Sample is heated
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3.3 Caffeine Extraction Procedure
This sample was placed into a separating funnel and 6 ml of dichloromethane
(DCM) was added. The caffeine was extracted by inverting the funnel at least
three times, venting the funnel after each inversion. Vigorous shaking will
produce an intractable emulsion, while extremely gentle mixing will fail to
extract the caffeine. The bottom layer containing dichloromethane (DCM) was
removed to a clean flask, leaving behind the layer of water and the extraction
procedure was repeated twice more and the solvent layers combined.
Figure 3 Bottom layer containing dichloromethane
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3.4 Separation of Caffeine
The dichloromethane was evaporated from the extract by heating the flask on
mantle or by covering with perforated aluminium foil and leave it for some time
and allow it to get evaporated and it was recovered in the other beaker using Heat
Reflux Extraction method. The residue obtained was whitish powder which was
considered to be pure caffeine. The mass of flask with residue was measured on
electronic scale.
Figure 4 Caffeine
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3.5 Murexide test
Confirmative Test for Caffeine Detection Murexide test can be carried out for
caffeine detection as follows:
1. In a watch glass, small amount of a sample with 2-3 drops of concentrated
hydrochloric acid is mixed. Use a glass rod for mixing.
2. Then we add a few small crystals of potassium chlorate and mix well.
3. Heat the watch glass until the sample is dry.
4. Allow to cool.
5. Add a drop of ammonium hydroxide solution. The sample should turn
purple.
Figure 5 Murexide Test
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IV. RESULT & DISCUSSION
Extraction of caffeine from tea and coffee was achieved by using
Dichloromethane as an extracting solvent.
S.NO
SAMPLE
AMOUNT OF
SAMPLE(g)
AMOUNT OF
CAFFEINE
EXTRACTED(g)
1
TEA
7
0.226
2
COFFEE
7
0.345
Table 1 Extraction of caffeine from tea and coffee
It was observed that the extraction efficiency of caffeine from various sources by
using dichloromethane was much higher than other solvents. Table 6.1 shows the
extraction efficiency of crude caffeine from tea and coffee leaves. The amount of
caffeine obtained from L- L extraction after further recrystallization was found to
be 3.37% from tea and 5.04% from coffee. We observed that coffee contained a
high amount of crude caffeine as compared to tea. To purify the crude caffeine,
similar procedures were utilized. The pure white crystalline caffeine isolated from
sources was found to melt at 238 C.
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The Infrared-spectrum of isolated caffeine showed similar absorption bands
similar to that given in literature. The Infrared-spectrum indicates the absolute
purity of the purified caffeine. We have developed a high-performance liquid
chromatography method for the determination of caffeine, which was carried by
High Performance Liquid Chromatography instead of using UV- Visible
spectrophotometer. We chose High performance liquid chromatography method
for the determination of caffeine, because High performance liquid
chromatography is the most widely used qualitative and quantitative
determination and separation method. This method is popular because it is non-
destructive and unlike gas chromatography may be applied to thermally liable
compounds. Moreover, it is also a very sensitive technique as it incorporates a
wide range of detection methods. With the use of post column derivatization
methods to improve selectivity and detection limits, High performance liquid
chromatography can easily be extended to trace determination of compounds that
do not usually provide adequate detector response.
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V. CONCLUSION
A method has been developed for the extraction, purification of caffeine from tea
and coffee. Caffeine from tea and coffee was extracted by liquid- liquid extraction
followed by recrystallization. The purified caffeine was then analysed by High
performance liquid chromatography. Effective characterization of caffeine was
achieved by determining IR spectrum, and employing a melting point apparatus
and differential scanning calorimeter. The serious concern about potential use of
caffeine for pathogenic effects has made it one of the most broadly studied drugs.
It provides clinicians with the information they require in order to understand,
diagnose and treat the effects of caffeine consumption in their patients.
As stated by ‘Barone, J.J. and Roberts, H.R.’ in their book ‘caffeine consumption’
that caffeine is a pharmacological active substance and depending on the dose,
can be a mild central nervous system stimulant. It is noted that caffeine is not
food but a drug working through nervous system. Excessive amount should be
avoided since caffeine consumed in large amounts has adverse health effects. In
particular, people suffering from high blood pressure should be advised to avoid
use of caffeine containing beverages since caffeine is known to increase the blood
pressure. In addition, those with coronary heart disease should avoid such
beverages as caffeine disrupts normal heart rhythm.
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VI. REFERENCES
1. Barone, J.J., Roberts, H.R. (1996) Caffeine Consumption, Food Chemistry
and Toxicology, McGraw-Hill, Newyork,34, 119
2. Arnaud, M. J. (1987) The Pharmacology of Caffeine, Prog Drug, 31, 273.
3. Islam, M. S, Rahman, M. M., Abedin, M.Z. (2002) Isolation of caffeine
from commercially available tea and tea waste, Jahangirnagar Uni. J.
Sci.,25,9.
4. Jeanne CS. (1987). Introductory clinical pharmacology. J. B. Uppimcott
Company, 3(19): 122-125.
5. Kaplan E, Holmes JH, Sapeika N (1974). Caffeine content of tea and
coffee. S. Afr. Med. J., 48: 510-511
6. Lawrence EL (1986). What you need to know about food and cooking for
health.
7. H. T. Debas, M. M. Cohen, I. B. Holubitsky, and R. Harrison. Caffeine-
Stimulated Acid and Pepsin Secretion: Dose-Response Studies,
Scandinavian Journal of Gastroenterology, August 1971, Vol. 6, No. 5,
Pages 453-457.
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8. Gebely, (2017). World of Tea. Retrieved from http://www.world of
tea.org/tea-Leary-oxidation.
9. Kevin Browsky. (2010). Caffeine Extraction’. Retrieved from
https://www.thewhistlingkettle.com/9/info/blog/caffeine- and match.
10. Williams, K. and Katherine M. (2011). Macro scale and micro scale
organic. Experiment, 6th ed. Brook/Cole, pg.213.
www.spider.com/chemical-structure.2424.html.
11. Betty kovacs. (2017). Caffeine newsletter; medicine net. Retrieved from
https://www.medicinenet.com/Coffee.
