Re: How can I measure ethanol content in fermenting fruit?

Hi Elizabeth,

What an interesting science fair project. I have spoken with several
professors in our department concerninig measuring ethanol. They couldn't
think of an easy method for measuring ethanol. Most of the methods require
sophisticated analytical instruments. One idea that we thought about was
the breathalyzer used to meausre alcohol levels in intoxicated people. If
you had the friut flies in a jar with the fruit, could you draw 5-10 ml of
air into a syringe and somehow introduce the air into the breathalyzer.
Perhaps, you could see if your local law enforecement personnel could work
with you. The actual attractants for the fruit flies may be the aromatic
compounds (ketones and aldehydes) formed during the fermentation of the
fruit rather than the ethanol. I certainly wish you the best with this project.

Al Bushway
Professor of Food Sciecne