The Fermentation of
Beverages by Yeast
By: Anna Gillin
Grade 9
Problem

Which common beverage has the
highest sugar concentration?
Research
Sources
Sugar
Yeast
Fermentation
CO2
Research
These are the sugars found in the beverages used in the experiment
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Coke- 27 g of sugar per 240 ml
• Fructose
• Glucose
Pepsi- 28 g of sugar per 240 ml
• Fructose
• Glucose
Diet Pepsi- 0 g of sugar per 240 ml
• Aspartame
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Hawaiian Punch- 20 g of sugar
per 240 ml
• Fructose
• Glucose
Apple Juice- 31 g of sugar per
240 ml
• Fructose
Sprite- 27 g of sugar per 240 ml
• Fructose
• Glucose
Research

Yeast
• Microscopic single celled organisms that are
•
•
classified in the Fungi family
Can utilize sugars both aerobically and
anaerobically
Baker’s Yeast
• Common strain of yeast used as a leavening agent
in baking bread
• Produces ethanol and carbon dioxide from sugars
anaerobically
Research

Fermentation
•
•
Fermentation of a sugar will result in CO2 gas
and alcohol production
Fermentation is a chemical reaction caused
by the interaction of a food molecule and a
substance
Hypothesis

If the beverage produces more bubbles
of carbon dioxide through fermentation,
then its sugars are best utilized by yeast.
Materials



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Graduated Pipet
Paraflim
Yeast- 10 ml per drink solution
Water- 10 ml per drink solution
Drink Solutions- 10 ml of each solution
•
•
•
•
•
•
Diet Pepsi
Coke
Pepsi
Apple Juice
Sprite
Hawaiian Punch
Procedure
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

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
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177 ml of each of the beverages were boiled
Each of the tubes were labeled with the name of the
drink solution
Yeast was added to the drink solution and withdrawn
into a small syringe
A piece of paraflim was placed over the syringe to
keep the solution inside
The height of gas bubbles in the syringe was
measured
The procedure was continued for each of the drink
solutions
The procedure was repeated for 3 trials
Procedure


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The independent variable is the beverages.
The dependent variable is the CO2
production.
The control variables are the water and
glucose.
The constants are the boil times and amount
of materials used such as yeast and
beverages.
Data
Carbon Dioxide (ml)
Carbon Dioxide Volume
0.6
0.5
0.4
0.3
0.2
0.1
0
Volume
Diet
Pepsi
Coke
Pepsi
Apple
Juice
Sugar Source
Sprite
Hawaiian
Punch
Conclusion

The hypothesis stated that if the drink
produced more bubbles of CO2 then its
sugars are best utilized by yeast.

The hypothesis was supported because
Diet Pepsi, which doesn’t contain any
sugars, did not ferment.
Improvements

The experiment could be expanded by
adding another drink with natural sugars
such as orange juice.

A more in depth study would be
examining the consumers of these
beverages and their health and weight
affected by the high correlation of the
sugars in drinks.
Works Cited


Fogel, Robert. "Fungal Factories: Gasohol and more."
Fun Facts about Fungi.
N.p., 13 Nov. 2006. Web. 21 Feb. 2010.
<http://herbarium.usu.edu/fungi/
FunFacts/Fermentation.htm>.
"5 Types of Soda and Why You Should Avoid 4 of Them."
Fit Hacks. N.p., 22 Feb.
2008. Web. 21 Feb. 2010.
<http://www.fithacks.com/index.php/2008/02/22/
the-5-types-of-soda-and-why-you-should-avoid-4-ofthem/>.
Works Cited


"Baker's Yeast." Wikipedia. N.p., 18 Feb. 2010. Web. 21
Feb. 2010.
<http://en.wikipedia.org/wiki/Baker's_yeast>
"Apple juice, canned or bottled, unsweetened, without
added ascorbic acid."
Nutrition Data. N.p., 20 Aug. 2008. Web. 21 Feb.
2010.
<http://www.nutritiondata.com/facts/fruits-and-fruitjuices/1822/2>.
Thank You

Please feel free to ask any questions
regarding my experiment