PM SHRI KENDRIYA
VIDYALAYA {O.F} BHUSAWAL
Department of Chemistry
Investigatory project
“ Comparative study of the rate of
fermentation of following materials :
wheat flour , gram flour , potato juice ,
carrot juice , etc.”
Submitted To – Priya Singh
Submitted By – Anushka N. Bavaskar
Class – XII A
Roll No. –
CERTIFICATE
This to certify that Anushka N.
Bavaskar of Class XII A (science) has
prepared the report on the project
entitled “Comparative study of the
rate of fermentation of following
materials : wheat flour , gram
flour , potato juice , carrot juice ,
etc.” under the guidance of Mrs.
Priya Singh ( PGT Chemistry ) in the
partial fulfilment by the central
board of secondary education
(CBSE) leading to the award of the
annual examination of the year
2024 -2025
Teacher Principal Examiner
ACKNOWLEDGEMENT
I would like to express my special
thanks of gratitude to my
chemistry teacher Mrs. Priya Singh
, who helped me throughout this
chemistry investigatory project.
I am grateful for the support and
guidance provided by my teacher
which allowed me to complete
this project on chemistry within
the limited time frame.
I am also thankful to my parents
and friends for their constant
encouragement and cooperation
throughout the project.
INDEX
- AIM
- INTRODUCTION
- THEORY
- MATERIALS REQUIRED
- PROCEDURE
- OBSERVATIONS
- BIBLIOGRAPHY
AIM
To compare the rate of fermentation of
given sample of wheat flour , rice flour
and potato juice using yeast.
The purpose of the experiment is – to
compare the rage of fermentation of
the given samples of wheat flour ,
gram flour , rice flour and potato juice. I
became interested in this idea when I
saw some experiments om
fermentation and wanted to find out
some scientific facts about
fermentation. The primary benefit of
fermentation is the conversion of
sugars and other carbohydrates ,e.g.,
converting juice into wine , grains into
beer , carbohydrates into carbon
dioxide to leaven bread , and sugars in
vegetables into preservative organic
acids
INTRODUCTION
Fermentation is a metabolic process serving for some
microorganisms to get energy through digestion of
simple fermentable sugars, mostly glucose and fructose.
In bakery fermentation, the production of carbon
dioxide (CO2) is required as it serves for fluffing up the
dough. The principle of rheological apparatus, used for
the evaluation of fermented dough properties during its
maturation, is the measurement of gaseous volume or
pressure produced. Fermentograph SJA (Sweden) or
advanced type Rheofermentometer (Chopin, France)
can describe this dough behaviour . The purpose of
fermentation is to bring dough to the optimum
condition for baking . Fermentation typically is the
conversion of carbohydrates to alcohols and carbon
dioxide or organic acids using yeasts, bacteria, or a
combination thereof, under anaerobic conditions. A
more restricted definition of fermentation is the
chemical conversion of sugars into ethanol. The science
of fermentation is known as zymology. Fermentation
usually implies that the action of microorganisms is
desirable, and the process is used to produce alcoholic
beverages such as wine, beer and cider. Fermentation is
also employed in preservation techniques to create
lactic acid in sour foods such as sauerkraut, dry
sausages, kimchi and yoghurt, or vinegar for use
in pickling foods.
Wheat flour , gram flour, rice flour and potatoes contains
starch as the major constituent. Starch present in these
food materials is first brought into solution.in the
presence of enzyme diastase, starch undergo
fermentation to give maltose. Starch gives blue-violet
color with iodine whereas product of fermentation starch
do not give any characteristic color. When the
fermentation is complete the reaction mixture stops
giving blue-violet color with iodine solution. By comparing
the time required for completion of fermentation of equal
amounts of different substances containing starch the
rates of fermentation can be compared. The enzyme
diastase is obtained by germination of moist barley seeds
in dark at 15 degree Celsius. When the germination is
complete the temperature is raised to 60 degree celsius
to stop further growth. The seeds are crushed into water
and filtered. The filtrate contains enzyme diastase and is
called malt extract.
THEORY
In biochemistry, fermentation theory refers
to the historical study of models of natural
fermentation processes, especially alcoholic
and lactic acid fermentation. Notable
contributors to the theory include
Justus Von Liebig and Louis Pasteur, the
latter of whom developed a purely microbial
basis for the fermentation process based on
his experiments. Pasteur's work on
fermentation later led to his development of
the germ theory of disease, which put the
concept of spontaneous generation to rest .
Although the fermentation process had been
used extensively throughout history prior to
the origin of Pasteur's prevailing theories, the
underlying biological and chemical processes
were not fully understood. In the
contemporary, fermentation is used in the
production of various alcoholic beverages,
foodstuffs, and medications
MATERIALS REQUIRED
1) Conical Flask
2) Test Tube
3) Funnel
4) Filter paper
5) Water bath
6) 1% lodine Solution
7) Yeast
8) Wheat flour
9) Gram Flour
10) Rice Flour
11) Potato
12) Aqueous NaCl solution
PROCEDURE
1) Take 5 grams of wheat flour in 100 ml conical
flask and add 30 ml of distilled water.
2) Boil the contents of the flask for about 5
minutes
3) Filter the above contents after cooling, the
filtrate obtained is wheat flour extract.
4) To the wheat flour extract. taken in a conical
flask. Add 5 ml of 1% aq. NaCl solution.
5) Keep this flask in a water bath maintained at
a temperature of 50-60 degree Celsius . Add 2
ml of malt extract.
6) After 2 minutes take 2 drops of the reaction
mixture and add to diluted iodine solution.
7) Repeat step 6 after every 2 minutes. When
no bluish color is produced the fermentation is
complete.
8) Record the total time taken for completion of
fermentation.
9) Repeat the experiment with gram flour
extract , rice flour extract , potato extract and
record the observations
OBSERVATIONS
Time required for the fermentation –
1) Wheat flour – 10 hours
2) Gram flour – 12.5 hours
3) Rice flour – 15 hours
4) Potato – 13 hours
CONCLUSION
1) Rice flour takes maximum time
for fermentation.
2) Wheat flour takes the minimum
time for fermentation
BIBLIOGRAPHY
1. Chemistry Textbook class XII.
2. Chemistry manual
3. www.Wikipedia.com/Pigments
4. www.google.com
5. www.1000sciencefairprojects.c
om
6. www.ionicviper.org
7. www.webexhibits.org
8. www.compoundchem.com
