Which Yeast Mixture Rises the Most?
Researched by Tyler W. 2001-02	PURPOSE  HYPOTHESIS  EXPERIMENT DESIGN  MATERIALS  PROCEDURES  RESULTS  CONCLUSION  RESEARCH REPORT  BIBLIOGRAPHY  ACKNOWLEDGEMENTS  ABOUT THE AUTHOR

The purpose of this experiment was to gain accurate knowledge of which cooking yeast raised the most and produced the most yeast.

I became interested in this idea when I learned to cook four years ago and wondered whether I could get a yeast that would raise my mixture higher.

The information gained from this experiment could help many professional cooks and also home cooks know which yeast raised the most.

My hypothesis is that Fleischmann’s yeast will make the mixture rise the most and produce the most yeast. 

I base my hypothesis on the quote from Tammy, "I have used both of the yeasts you are using in your experiment and Fleischmann’s rised the most." 

The constants in this study were: 
-The amount of ingredients used
-The utensils used
-The bowl used
-The time the yeast mixture was left to rise
-The amount of time the mixture was stirred
-The temperature the yeast mixture was left to rise

The manipulated variable was the type of yeast that I used in the experiment.

The responding variable was the height that the yeast mixture raised. 

To measure the responding variable I measured in centimeters how high each yeast mixture raised with each different type of yeast. 

1. Gather all of the materials needed to do this project.
2. Label first five glass bowls one through five.
3. Put 1/2-cup sugar into each large glass bowl.
4. Add 1 tablespoon of Fleischmann’s yeast to each of the five bowls.
5. Check temperature of hot water then; add 1 cup of hot water to each bowl simultaneously.  Start the timer immediately after pouring the water into each of the bowls.
6. Slightly swish the mixture (with timer going) for ten seconds.
7. Time each mixture for 30 minutes, then insert a ruler straight down into the mixture, (taking the measurement four inches form the side) and measure the number of centimeters and write it down immediately. 
8. Repeat steps three through seven with the Redstar Yeast.
9. Record ALL results and convert onto graphs.

The original purpose of this experiment was to figure out which type of yeast raised the most and produced the most yeast while rising.

The results of the experiment were that the Fleischmann’s Yeast raised substantially higher than the competitor Redstar. 
View My Data and Graphs

My hypothesis was that Fleischmann’s Yeast would rise higher and produce more yeast to bake with.

The results indicate that this hypothesis should be accepted Fleischmann’s Yeast rises.

Because of the results of this experiment, I wonder if any other cooks will change the type of yeasts they bake with.

If I were to conduct this project again I would use several types of yeast and do ten, instead of five, trials for each type of yeast.
 
 
 
 
 
 
 

Research Report What is Yeast? Man used yeast before he knew how to read, write, or even talk. Research by some modern day scientists shows that ancient Egypt was the main area for most modern bread making.  Archaeologists digging in Egypt found grinding stones and baking chambers that are well over 5,000 years old, showing that baking and yeast were common back then. Certain Hieroglyphics from Egyptian tombs suggest that they, (the Egyptians) used yeast to rise their bread over 5,000 years ago.  Most Egyptians did not know of the leavening process, but knew that yeast could be used to rise their bread very well.  The chemical action that occurs when yeast is put into a liquid or heated up is called fermentation.  Egyptians probably thought that fermentation was a mysterious phenomenon.  In the early 1400’s,mixtures of leavening (for bread) were made by natural contamination of the one of these: wild yeast or lactobacilli. (Found in dairy)  Leaven, which was mentioned once or twice in the Bible, was a very soft, doughy medium kept from one baking bread for another.  A small part of this doughy medium was used to start the next loaf of bread.  This medium could be kept for no longer than two days, so baking all the time was imminent. Yeast is a very small type of fungi that scientists call microorganisms.  These "fungi" are tiny cocci that can only be seen in very large amounts or under a microscope.  These tiny cocci take over twenty billion to weight one gram or one twenty eighth of an ounce.  Yeast cells eat other nutrients, such as sugars to survive and expand.  The process called alcohol fermentation makes very useful products such as carbon dioxide and ethyl alcohol.  These products are released by the yeast cells into the surrounding area.  "Baking Yeasts" The scientific name for a single species of yeast is called SACCHAROMYCES CEREVISIAE or, a very strong sugar consuming fungus.  Fermentation happens naturally in nature also.  For example, many berries burst open in late fall when they are over ripened and full of sugar.  Some of the natural yeast from the surrounding air lodge onto the berries, and then ferment, causing alcohol.  In some of the local fermentation plants, grape juice is fermented for wine by letting all of the gas out of the brewery.  This gas is not harmful and cannot hurt you at all.  In bread baking, when all of the yeast ferments, the carbon dioxide gas cannot escape and is trapped in the dough, causing the bread to rise very slowly.  "Brewer’s Yeast" Brewer’s Yeast is an inactive yeast that has no power to ferment. Brewer’s Yeast is sold for its nutritional values as also its vitamins. A by-product of the brewing industry, brewer’s yeast is very inexpensive and valuable. After 5 to 10 successful beer fermentations, the yeast, due to increasing contamination of air, loses its ability to expand and is no longer capable of making beer. The yeast then becomes an abundance and can be used for the production of bread or in feed formulas. Over the years the term Brewer’s Yeast has become generic and very cheap. Primarily grown to be a baker’s yeast, it is often sold as Brewer’s yeast because the term is familiar to most consumers. The producing and airing of this yeast is carefully controlled so that it remains inactive and easily digestible. Another type yet again of Brewer’s yeast is labeled as Debittered Brewer’s Yeast and is almost certain to be a brewer’s yeast. A product just labeled as brewer’s yeast may be brewer’s yeast, or it may become an inactive baker’s yeast. Nutritional Value of Yeast Brewers yeast is not sold for baking, but rather for health.  It is sold for it’s large amount of vitamins and minerals.  Some of the vitamins are all of the vitamin B factors, and some of the vitamin C factors.  All of the vitamin B factors are: Thiamin, Riboflavin, Niacin, Pyridoxine, Pantothenic Acid, Biotin, Choline, Inositol, Folic Acid, Paraminobenzoic Acid.  Another type of yeast is the Quick Rise yeast by Red Star.  Red Star created a very highly active strain of yeast by protoplast fusion.  Adding absorbic acid as an enhancer does this protoplast fusion very easily.  Flour, fat, and liquids, always are in breads and doughs.  These elements are what causes yeast to ferment and are what are valuable to the taste of the yeast.  Facts about Yeast Yeast ferments sugar and starch in flour producing carbon dioxide and ethyl alcohol gases. Too much sugar will slow the yeast activity. Sweet breads are usually dense and not as large as sandwich breads because of too much sugar.White sugar, brown sugar, honey, and molasses may all be interchanged equally in bread as sweeteners.Baking Yeast and Brewers Yeast are not like the bacterium yeast.Most artificial sweeteners (such as aspartame) may not be substituted in bread making as they are proteins and cannot ferment. Yeast is almost everywhere, living airborne and on objects.Yeast was discovered as early as the 1500’s and was thought to be the work of witchcraft. (Because when they would put their bread outside to rise, they did not know that bacteria were getting into the bread.)

BIBLIOGRAPHY * Author Unknown.   "Yeast," World Book Encyclopedia, 1998. * "Redstar Yeast" The Science of Yeast December 23,2001 http://www.redstaryeast.net/sciencefree.html * "Redstar Yeast Homepage" Type of Yeasts December 23,2001 http://www.redstaryeast.com/ * "Bread World" The History of Science December 27,2001 http://www.breadworld.com/sciencehistory/science.asp * "Redstar Yeasts" The Pricing and making of Yeast January 10,2002 * http://search.metacrawler.com/crawler?general=Redstar+Yeast+Prices&type=Search&method=1&go2net=1 * "Redstar Yeast Homepage" Comparing Yeasts November 15,2001 http://www.redstaryeast.com/science.htm * "Bread World Expanse" Fleischmann’s Yeast November 15,2001 http://www.breadworld.com/index.cfm * "Redstar’s Yeast Site" Science of the Yeasts December 5,2001 http://www.redstaryeast.com/sciencefree.html

• I would like to thank my mom for letting me use her kitchen and for helping explain some of the facts about yeast to me.
• I would like to thank Mrs. Helms for helping me in any way she could to complete my project.
• I would also like to thank my grandmother for giving me her opinion on how to use the yeast mixtures to my advantage.
• I would like to thank my family also for all of the support they gave me and for helping me to time my project.
• I would like to thank Mr. Newkirk for all he did to help on this science project.

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