Question

Anyone have insight on the process of ethanol fermentation by yeast on various types of artificial sweeteners? Equal produced the most amount of waste, while sugar and Splenda produced about the same amount, and Truvia produced the least. I know why Truvia produced the least. Why did equal produce the most? Scientific articles welcome. Thanks!

Answer 1

Is this chemistry related? :)

Answer 2

I wish, this way I could go into the structure of the bonds. However, it's a bio lab for my bio 111 class.

Answer 3

That's ok, let me try to help you out. To start, let's look at a little background.
Do you know what the yeast was reacting with?

Answer 4

Yea ok. So control variables: 2.5 g of dry active yeast, 10 mL of 55C water, and 2.5 g of sweetener were placed into plastic bags. The mixture fermented for 10 minutes in a 55C water bath. We then measured the independent variable, amount of CO2 produced by each reaction. The yeast was fermenting the sugar via glycolysis which changes glucose into 2 pyruvate. This dealt with alcohol fermentation so the 2 pyruvate were converted to acetaldehyde and then to 2 ethanol. CO2 was given off as waste.

Answer 5

I see. If more CO2 is produced, should the sample have more or less sugar?

Answer 6

all of the samples used the same amount of sweetener...so that's where I'm coming up short. I looked at the ingredients of each type of sweetener...Truvia produced the least amount of CO2...my theory is that this is because the main ingredient in truvia is a sugar alcohol that has already been fermented. The yeast needs glucose to undergo glycolysis and it wasn't there. Ok, next I have sugar-sucrose which is a disaccharide (egh spelling) made of glucose and fructose so an enzyme is needed to break down the sucrose before glycolysis can occur. This was my control and produced the 2nd to least amt of waste. The Equal is composed of dextrose which is glucose from corn, maltodextrin which is not fermented by yeast, and aspartame which...is unstable at high temperatures...but I couldn't figure out if the yeast ferments that or not. I know it has nitrogen in it but don't know if that means anything. The equal produced the most amount of waste...and then the splenda (sucralose) produced just a little bit more than the regular sugar.

Answer 7

I believe that yeast can ferment dextrose, which is probably why equal was able to ferment as shown by your results. It could be the other "artificial" sweenteners in the Equal helped the process, but that's just a hypothesis

Answer 8

Yes, dextrose is chemically similar to glucose so yeast can ferment the dextrose. I am confused as to why it fermented the equal the most though. Splenda also has dextrose and maltodextrin as well as the sucralose. So I do not know why more waste wasn't produced by the Spenda reaction. I compared my lab data with the class data and found our results to be synonymous once the outliers were removed. I can't seem to find scholarly articles to back my work and that's a part of the lab itself. Do you know of any sites other than google scholar that might help?

Answer 9

From what background I can find most sugar forms (sucrose, fructose, glucose, etc) are fermented by yeast. This explains why all or your sweeteners did show results

Answer 10

Yes, that is true. For my lab discussion I am attempting to explain why one would produce more gas than the others though or why Splenda and sugar produced similar amounts.

Answer 11

Thank you for your assistance. I really appreciate it.

Answer 12

regular sugar is sucrose, glucose is a simpler structure so it's probably fermented easier/faster..this would explain why the Equal produced more. Also, although you used equal masses of each sweetener we don't know the concentration of each sugar type in each one. Splenda may have had a smaller percentage of dextrose compared to Equal

I think for Equal compared to sugar it's most likely caused by the structure of the sugar (dextrose - similar to glucose compared to sucrose)

Answer 13

For Splenda it probably has a smaller amount of the same type of sugar as Equal

I'm looking for scholary articles as well. So far everything I've found it just other people's results to a similar lab

Answer 14

Nice, I do have all of that in the discussion section of my lab so far. I'm just having an issue finding the articles to support it. I guess worst comes to worst I could always cite another experiment that shows similar results, but I am unfamiliar with where to look for those. I keep finding discussion boards where people are talking about it...but I definitely cannot use those in my lab write up. :)

Answer 15

no problem I found one article about wine fermentation using yeast'

http://onlinelibrary.wiley.com/doi/10.1016/j.femsyr.2004.02.005/pdf

this one actually compared glucose and fructose, but in the abstract they state "All strains showed preference for glucose" This supports some of your results as well.

Answer 16

here's another one:
http://connection.ebscohost.com/c/articles/31746029/effect-different-sugars-rate-fermentation-yeast

Answer 17

this one you may have to access through a library, but the abstract seems to be what your looking for

Answer 18

I did see those earlier and realized I didn't have access to the ebsco one. Thank you for your assistance

Answer 19

=)