Science Buddies: "Ask an Expert"

Hi,
i am doing research on how to do my experament and i was wondering if you could use a fermentation tube to collect CO2 and judge how the yeast is reproducing or growing ? Please help.
Thanks a bunch
vonadara

dear vonadara,

thank you for contacting science buddies. your project sounds interesting. Regarding your question, a fermentation tube can be used to measure the amount of co2 from fermenting yeast. This amount can be used to quantify fermentation. I found by a google search another protocol that calls for measuring the amount of co2 from yeast fermentation. (http://wci.wrdsb.on.ca/Science/SBI%204U ... tation.pdf) You can substitute the syringe with a test tube or graduated cylinder and the glucose solution (which would be your control in the experiment) with sugar substitutes. Also, I want to remind you to be careful when working with yeast because it can be harmful to humans.

good luck,
scienceexpert123

Thanks scienceexpert123
That is a great site it should help a lot
Thanks agian
vonadara

Hello
I have another question what is the chemical make up of sugar substitutes like aspartame,saccharin,acesufame-k and corn syrup?also what are the comerchial names of these substitutes? (sorry about spelling i am not very good at it )
thanks agian
vonadara

Hi Vondara,
I just wanted to add that we have our own project related to measuring yeast metabolism here:
https://www.sciencebuddies.org/science- ... p009.shtml
Of course, you can ignore the parts about varying the oxygen concentrations.

For your questions about the chemical makeup and commercial names of those sugar substitutes, I recommend doing an internet search for those names. If you can't find information on one of them, or are confused about what you find, we'll be glad to help.

Also, I merged your second topic with your original topic so that the experts can follow the the progress of your project and keep track of assistance that you have already received. Please keep future posts related to your project in this topic.

Thanks and good luck,
Chris

Thank you ChrisG
That will help me find more things to research.I will keep all my posts in here i didn`t think you could or should do that.
thanks agian.
vonadara

Hi its me again just want to know if there are any safety tips you have for handling yeast. It is the packaged kind but i dont know
vonadara

Hi,
Basic precautions for working with powdered yeast are to avoid inhalation or direct contact with skin or eyes. The packaged bakers yeast is granulated, which makes it easier to handle and less messy.If you do get some yeast on you, just wash it off. Most people would consider yeast "non-toxic" but as with any substance, there are some potential hazards.
Please let us know if you need more info about safety.
Thanks,
Chris

Oh ok thanks Chris I don`t want to get sick. I will be careful and follow the guide lines my teacher gave me about working with dangerous subtances.
Thanks agian
vonadara

Sounds like a good plan, Vonadara. I'm sure you won't get sick.
Good luck,
Chris

Thanks I wont worry about it
vonadara

Hello agian i was wondering if you had any info on how much carbon dioxide is produced by yeast on average?
Thanks
vonadara

Hi,
Well it depends on what temperature you are measuring carbon dioxide production at...but you can check out this website for some experimental data-
http://en.wikibooks.org/wiki/GCSE_Scien ... emperature
hope this helps, good luck!

Hi Vonadara,

Yeast will produce 6 molecules of carbon dioxide for every 6-carbon sugar that they use. You should have had some chemistry by now, so here is the formula for the fermentation:

C6H12O6 (sugar, such as glucose) + 6O2 (oxygen) -> 6CO2 (carbon dioxide) + 6H2O + 38 ATP(energy)

As Stary13 mentioned, the volume of the carbon dioxide depends on the temperature, and also the pressure.

We use artificial sweeteners because they taste sweet, but can't be used by humans as an energy source. What artificial sweeteners are you planning to use? Do you think the yeast will be able to use them as an energy source and produce carbon dioxide?

Donna Hardy

Thanks Donna Hardy and staryl13
That will help I was thinking about using aspartame, corn syrup, and saccharin. I was going to make the temperature around room temperature.Thnks again.
vonadara

Hello I am having trouble locating the consentration of sugar substitutes in the brands like Sweet`nlow, Equal, splenda,and Nutrasweet. please help.
vonadara

Hi Vonadara,

I'm not sure exactly what you are looking for, but typically you can find the relative amounts of ingredients on the back of the box or packet. For example, a 1g packet of Splenda claims to contain less than 1g of sugar, and lists its ingredients as dextrose, maltodextrin, and sucralose. Dextrose is just D-glucose, or sugar (see http://en.wikipedia.org/wiki/Glucose). Maltodextrin is another polysaccharide (sugar), just a different form (see http://en.wikipedia.org/wiki/Dextrin). Sucralose is the artificial sweetener (see http://en.wikipedia.org/wiki/Sucralose). You can also check out the Splenda website (http://www.splenda.com/page.jhtml?id=sp ... rie.inc#q0) to get more information.

From the amounts of different ingredients, you can calculate the relative amounts of each ingredient (sugar vs. artificial sweetener). It may take some looking at the products in the grocery store or on websites, but you should be able to get this information.

I hope this helps. Post again if you're still having trouble.

Cheers,
Heather

I need help setting up my data table. Im testing How sugar substitues affect Yeast reproduction with splenda, sweet n low, and sugar. i have no clue how i should set it up

Hi Lopezjosh51,

What did you measure? Did you count the amount of yeast (% coverage) over a certain amount of time or the number of colonies? Did you measure the amount of CO2 produced by the yeast?

The way you present your data will depend on what you measured. If you want to organize your data into a table, you could have columns for the different treatments (Splenda, Sweet N Low, Sugar) and put the variables you measured as headings to each row. Your data might also lend themselves to a bar graph.

If you let us know exactly what you measured, we can give you more details about the best way to present your data.

Heather