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My son is in 5th grade and wants to be a chef. We were excited about this project but are getting no results. There is no gas displacement. We are measuring, the cap is air tight. I am wondering if the diameter of our tube is too small. I am getting discouraged- running out of time.
Thanks,
Jane and Owen
yeast and sugar substitutes
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jhenderson
- Posts: 1
- Joined: Mon Apr 20, 2015 8:20 pm
- Occupation: stagehand
- Project Question: we are doing the yeast reproduction in sugar substitutes project. The yeast is definitely bubbling and the seal is tight on our container but there is not gas being displaced. What might be wrong? I thought maybe my diameter of the plastic tubing might be too small. Are you supposed to have any water in the tubing before you put it up the cylinder taped to the pail?
- Project Due Date: May 4
- Project Status: I am conducting my research
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skuzniewski
- Posts: 14
- Joined: Fri Feb 13, 2015 5:53 pm
- Occupation: scientist
- Project Question: to help answer science questions
- Project Due Date: n/a
- Project Status: Not applicable
Re: yeast and sugar substitutes
Jane and Owen,
I am not sure what your method was but I think you are supposed to have water in the tubing because the yeast needs to the water to produce the carbon dioxide.
If it might help, here 's a simple write-up report on the same objective of the experiment: http://biosurvey.ou.edu/oas/06/paper/malatinsky.pdf
The gas bubbled and so the increase in height of the mixture in the test tube.
Could any one of these might also be possible?
1. The yeast might not viable and so no bubbles. This could be if the yeast is too old or if the yeast pack was left open for a long time and so the yeast dried up.
2. Too hot or too cold water. Too hot can kill the yeast and too cold is not feasible for the chemical reaction to proceed to produce the carbon dioxide. I will recommend warm, tap water.
2. Too much sugar. Too much sugar can kill the yeast.
Good luck!
-Sally Kuzniewski
I am not sure what your method was but I think you are supposed to have water in the tubing because the yeast needs to the water to produce the carbon dioxide.
If it might help, here 's a simple write-up report on the same objective of the experiment: http://biosurvey.ou.edu/oas/06/paper/malatinsky.pdf
The gas bubbled and so the increase in height of the mixture in the test tube.
Could any one of these might also be possible?
1. The yeast might not viable and so no bubbles. This could be if the yeast is too old or if the yeast pack was left open for a long time and so the yeast dried up.
2. Too hot or too cold water. Too hot can kill the yeast and too cold is not feasible for the chemical reaction to proceed to produce the carbon dioxide. I will recommend warm, tap water.
2. Too much sugar. Too much sugar can kill the yeast.
Good luck!
-Sally Kuzniewski