80 ĐỀ THI THỬ TUYỂN SINH TIẾNG ANH VÀO 10 SỞ GD – ĐT THÀNH PHỐ HỒ CHÍ MINH NĂ...
CHEMISTRY INVESTIGATORY PROJECT by prerna.pdf
1. ARMY PUBLIC SCHOOL
GWALIOR
NAME : SHIKHA KUMARI
CLASS : XII B
SUBJECT : CHEMISTRY
SUBMITTED TO : MRS MITHLESH
CHAUHAN
Army Public School , Gwalior
2. C H E MIS T R Y
IN V E S T IG A T O R Y
P R O J E C T
Chemistry Integration
project
TOPIC : COMPARITIVE
STUDY OF THE RATE OF
FERMENTATION OF
VARIOUS FOOD
MATERIALS
3. ACKNOWLEDGEMENT
I would like to express my special thanks of gratitude to
“Mrs. Mithlesh Chauhan’’ Chemistry teacher at
“ARMY PUBLIC SCHOOL GWALIOR” for their able guidance and
support in completing my project.
I would also like to extend my gratitude to the Principal Sir
“Dr. Arvind Kumar Sikarwar’’ and Vice Principal Ma’am
“ Mrs. Vivian Singh’’ for providing me with all the facility that
was required.
Shikha Kumari
XII B
4. CERTIFICATE
This is to certify that “Shikha Kumari’’ student of
class “XII B” of your school has successfully
completed their Chemistry Investigatory Project
on topic “Comparitive study of the rate of
fermentation of various food materials”under
the guidance of “Mrs. Mithlesh Chauhan’’.
---------------- -------------
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Mrs.Mithlesh Chauhan Shikha
5. INDEX
• Introduction
• History
• Experiment 1
• Procedure
• Observation
• Result
• Experiment 2
• Procedure
• Observation
• Result
• Bibliography
6. INTRODUCTION
Fermentation is the slow decomposition of complex
organic compounds into simpler compounds by the
action of enzymes.
Enzymes are complex organic compounds , generally
proteins.
There are many examples of fermentation processes which
we came across ; souring of milk or curd, bread making,
wine making and brewing.
Fermentation word derives from Latin (Ferver which means
‘to boil’). As during fermentation there is lot of frothing
of the liquid due to the evolution of carbon dioxide, it
gives the appereances as if it is boiling.
7. HISTORY
Since fruits ferment naturally, fermentation preceds
human history. The earliest evidence of wine
making dates from eight thousand years ago in
Georgia, in the Caucasus area. There is strong
evidences that people were fermenting
beverages in Babylon circa 5000 BC. French
chemist Louis Pasteur the first known zymologist,
when in 1854 he connected yeast to
fermentation. Pasteur originally defined
fermentation as “respiration without air’’.
8. EXPERIMENT 1
AIM :- To compare the rates of fermentation of the
following fruit or vegetable juices (i) Apple juice (ii)
Orange juice (iii) Carrot juice.
REQUIREMENTS :- Conical flasks (250ml)
Test tubes and water bath
Apple juice
Orange juice
Carrot juice
Fehling solution A
Fehling solution B
Solution of Pasteur salts and distilled water
9. PROCEDURE:-
• Take 5.0ml of apple juice in a clean 250ml conical flask and dilute it
with 50ml of distilled water.
• Add 2.0 g of Baker’s yeast and 5.0ml of Pasteur’s salts to the above
conical flask.
• Shake well the contents of the flask and maintain the temperature
of the reaction mixture between 35 – 40 C.
• After 10 minutes take 5 drops of the reaction mixture from the flask
and add to a test tube containing 2ml of Fehling reagent.
• Place the test tube in boiling water bath for about 2min and note
the colour of the solution or precipitate.
• Repeat the step 4 after every 10 min. When the reaction mixture
stop giving red colour or precipitate with Fehling reagent, the
completion of fermentation is indicated.
• Note the time taken for completion of fermentation.
• Repeat the above experiment by taking 5.0 ml of carrot juice.
11. OBSERVATIONS
• Volume of fruit juice taken = 5.0ml
• Volume of distilled water added = 50.0ml
• Weigt of Baker’s yeast added = 2.0g
• Volume of solution of Pasteur’s salts = 5.0ml
12. RESULT
• The rate of fermentation of apple juice is more
than the rate of fermentation of carrot juice.
13. EXPERIMENT 2
AIM :- To compare the rates of fermentation of the given
samples of wheat flour, gram flour, rice and potatoes.
REQUIREMENTS :- Wheat flour
Gram flour
Rice flour
Potatoes
1% iodine solution
Conical flasks
Test tubes
Funnel
Filter paper
Water bath
14. PROCEDURE
• Take 5.0g of wheat flour in a 100ml conical flask and add 30ml of
distilled water.
• Boil the contents of the flask for about 5 min.
• Filter the above contents after cooling. The filterate obtained is
wheat flour extract.
• To the wheat flour extract taken in a conical flask, add 5ml of 1%
aqueous NaCl solution.
• Keep this flask in a water bath maintained at a temperature 50-60
C. Add 2ml of malt extract.
• After 2 min take 2 drops of the reaction mixture and add to dilute
iodine solution. Note the colour produced.
• Repeat step 6 every 2 min. When no bluish colour is produced the
fermentation is complete. Record the total time taken for
completion of fermentation.
• Repeat the experiment with gram flour extract, rice flour extract,
potato extract and record the observations.
