North American Fruit Explorers mailing list at ibiblio

[Lucky Pittman <lucky.pittman@murraystate.edu>]

At 06:35 PM 9/26/2002 +0000, Del rote:
"wine is wine, vinegar is vinegar"  My wife doesn't believe it, I'll ride 
the fence in ignorance.....but we both remember hearing that a fruit fly in 
a wine bottle can make wine into vinegar.....and we have a bottle of   'red 
wine vinegar'..?

Here's where my industrial microbiology course from my college days, years 
ago, comes in handy.

They may be doing it differently on an industrial scale now, but 
traditionally, vinegar has been made by allowing the fermentation 
of  carbohydrates - the sugars/starches in fruits, grains, etc. to produce 
ethanol.  So long as this process is kept under anaerobic conditions, when 
the alcohol level reaches the point that it kills off the yeasts, you end 
up with a stable alcohol product.  But, if anaerobic conditions are lost 
and  Acetobacter bacteria, which are ubiquitous in nature, are introduced( 
like on that fruit fly) the Acetobacter organisms can then convert the 
ethanol to acetic acid(vinegar).


Lucky Pittman
USDA Zone 6
Hopkinsville, KY