I am doing an experimental design for a yeast fermentation experiment.
I am asked to design a fermentation experiment using one or two of the following substrates:
-Corn syrup solution (in water)
-(Kernel extract + Cob extract + stem extract) blended in boiling water and filtered to remove solids
I also have the option of modifying the substrates by using amylase to break down starch in the solution.
Let's say I choose Corn syrup, the question is:
How are the substrate modified by the yeast cells so that they can be used for fermentation ?
Fermentation is the process of yeast cells breaking down sugars into simpler organic compounds like ethanol, carbon dioxide, and water. The yeast cells don't really do anything special to prepare the sugar molecules for fermentation, but in general, the simpler the sugar molecules are the faster and more efficiently the yeast cells will be able to break them down.
It seems that you basically have a choice of using corn syrup or whole corn extract. The corn syrup will be a simpler set of sugars that have already been broken down somewhat from corn starch. The corn sugars are more complex starches. Boiling the corn kernals and fibers will extract them into the water and help to break down the starches. The corn syrup will probably ferment a bit easier as a result of this. Adding amylase to either sugars will help break them down even further, thus making fermentation with the yeast even easier. But the yeast itself does not really do any pre-modification work on the sugars.