the effect of different levels of ph on the fermentation of yeast the effect of different levels of...
TRANSCRIPT
![Page 1: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/1.jpg)
The Effect of Different Levels of pH on the Fermentation of Yeast
By Rachel Koch
![Page 2: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/2.jpg)
Hypothesis and Problem StatementProblem: How do different levels of pH in the environment around yeast effect its fermentation?Hypothesis:If the environment around the yeast has a higher pH, then the yeast will create more CO2.
![Page 3: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/3.jpg)
Background Research Yeast: microorganism, Eukaryotic
domain and the Fungi kingdom
Baker’s yeast: digests sugar
Fermentation: release carbon dioxide
Energy and warmth for fermentation
Dough rising is result of fermentation
![Page 4: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/4.jpg)
Design Diagram
Levels pH of 5 pH of 6 pH of 7(control)
pH of 8
Trials 5 5 5 5
Title: The Effect of Different Levels of PH on the Fermentation of Yeast
Hypothesis: If the environment around the yeast has a higher pH, then the yeast will create more CO2.
![Page 5: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/5.jpg)
Design Diagram cont.IV: pH levelDV: Height of dough(cm)Constants: Ingredients in dough
(besides IV), the measurements of each ingredient, temperature at which the dough is placed to ferment and the amount of time the yeast ferments.
![Page 6: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/6.jpg)
MaterialsFlourSugarInstant yeastWarm water/solutionOilSaltRulerHClNaOHOven
![Page 7: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/7.jpg)
Procedure
• Prepare pH solutions in lab with the instructor using NaOH for basic solutions and HCl for acidic solutions.
1. Heat water/solution to 35 degrees C.
2. Add flour, sugar, oil, yeast and salt to the warmed water/solution.
![Page 8: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/8.jpg)
Procedure cont.
3. Knead dough for about 8 minutes.
4. Measure the height of the dough.
5. Store dough in a warm place for 45 minutes to allow yeast to ferment.
![Page 9: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/9.jpg)
Procedure cont. 2 Put dough in the oven set to
54 degrees C and turn the oven off
6. Measure the final height that the dough raises with a ruler.
![Page 10: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/10.jpg)
Photodocumentation
![Page 11: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/11.jpg)
Data
pH 5 pH 6 pH 7 (control)
pH 8
Trial 1 4.5 cm 2 cm 4.5 cm 3.5 cm
Trial 2 5 cm 3 cm 4 cm 3 cm
Trial 3 5 cm 3 cm 4 cm 3.5 cm
Trial 4 5 cm 3.5 cm 4.5 cm 3 cm
Trial 5 4.5 cm 2.5 cm 4 cm 3 cm
Averages 4.8 cm 2.8 cm 4.2 cm 3.2 cm
![Page 12: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/12.jpg)
AveragesPH 5: 4.8 cmPH 6: 2.8 cmPH 7 (control): 4.2 cmPH 8: 3.2 cm
![Page 13: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/13.jpg)
Graph
pH 5 pH 6 pH 7 pH 80
1
2
3
4
5
6
Level of pH
Heig
ht
of
dou
gh
in
cm
.The Effect of Different Levels of pH on the Fermentation of
Yeast
![Page 14: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/14.jpg)
Statistical Analysis
Source of Variation
Sum of squares
Degrees of Freedom
Mean Squares
F Significance
Between 13.14 3 4.379 33.37 0.000
Error 2.1 16 0.1313
Total 15.24 19
ANOVA
![Page 15: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/15.jpg)
Conclusions
Hypothesis did not support data
Ideal environment is pH 4-6
Yeast ferments better in acidic
substances
Data is inaccurate
![Page 16: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/16.jpg)
Possible ErrorsOven temp. wasn’t exactly the
same every time
Measurements might not have
been exact
Measured every half centimeter
![Page 17: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/17.jpg)
Improvements
Could buy an alternative heating
devise
Measure ingredients more
carefully
Measure the height to a tenth of
a cm
![Page 18: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/18.jpg)
ReasoningLike to bake
Thought it was interesting that yeast makes dough rise
![Page 19: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/19.jpg)
ExtensionsTest other factors that effect
yeast fermentation, like:
oTemperature
oAmount of sugar
![Page 20: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/20.jpg)
Acknowledgements Mrs. Po Preparing solutionso Helping
Parentso Bought ingredients
![Page 21: The Effect of Different Levels of pH on the Fermentation of Yeast The Effect of Different Levels of pH on the Fermentation of Yeast By Rachel Koch](https://reader035.vdocuments.us/reader035/viewer/2022062421/56649dc55503460f94ab8319/html5/thumbnails/21.jpg)
Bibliography"Basic Bread." PrismNet : Austin TX VOIP, Broadband Colocation, Web Hosting. Web. 05 Oct.
2010. <http://www.io.com/~sjohn/bread.htm>.
"Fermentation." Utah State University: Intermountain Herbarium. Web. 04 Oct. 2010.
<http://herbarium.usu.edu/fungi/funfacts/Fermentation.htm>.
"What Are Yeasts?" Saccharomyces Genome Database. Web. 05 Oct. 2010.
<http://www.yeastgenome.org/VL-what_are_yeast.html>.
Campbell, Neil A., Jane B. Reece, Lawrence G. Mitchell, and Martha R. Taylor. Biology
Concepts & Connections. San Francisco: Benjamin Cummings, 2003. Print.
"Factors Effecting Fermentation." Web. 19 Dec. 2010.
<http://home.earthlink.net/~ggda/factors_effecting_fermentation.htm>.
"Yeast Fermentation in Baked Goods." Dakota Yeast. Web. 20 Dec. 2010.
<http://www.dakotayeast.com/help-fermentation.html>.