Originally Posted by Inarus
So I'm studying yeast for my biology class. I managed to talk my professor into allowing me to study the effects of sugar in a wort compared to the alcohol content of the finished product. Logic tells me the more sugar the more alcohol and most of the research I have done has backed this up. But What the hell, I want to try it. So dang, I have to brew 10 gallons of beer for a class, what a shame! But I'm running into the problem of how do I measure the sugar content of the wort? Any ideas? Is there a probe out there that will do it? Will a simple diabetes tester do it?
uh... is this for college or HS?
American brewer's usually measure the sugar content as specific gravity. You can get a hydrometer from any homebrew store to measure this. In europe and on a professional scale, Plato is usually the preferred measurement with is the %sugar in solution.
Brix is sometimes used, but is slightly misleading as Brix actually measures % sucrose in solution and this is not what wort really is, but in reality it works out close enough that brix = plato for as accurate as I care to be.
However, I hate to ruin your experiment but the more sugar in your starting solution, the more alcohol the yeast will make until they have reached their attenuation limit or alcohol tolerance limit. This has been known for hundreds if not thousands of years.
The formula for alcohol content in terms of specific gravity even shows that the more sugar, the more alcohol. (OG-FG * 131).
Have you ever made beer before? I would suspect you would have a hydrometer or refractometer if so. It takes a decent amount of equipment to make beer, and unless you do want to start this hobby, it looks like a pretty expensive experiment to me. You might consider just doing a sugar and water solution and then adding yeast for the purposes of the experiment to keep costs down. The results will be the same. (or do apple juice if you want a drinkable product afterwards.)