Friday, July 8, 2011

vinegar: a science lesson

     Got your goggles and lab coat on? It is time now for science class. Here is an exciting tidbit I learned from the other Food Maven, Arthur Schwartz... I mentioned it to you the other day.
     It is about vinegar. Here is his definition: Vinegar is the result of a sweet liquid spoiling not once, but two times.
     Fermentation resulting from spoiled fruit is wine. Grapes, for instance, ferment and become wine. Wine turns to wine vinegar.
     Fermented grain products are considered beer. Malted barley spoils to become beer, which then becomes malt vinegar. This is a simplified version of the process, but you get the idea.
     In the same process, juice from apples ferment to cider, which becomes apple cider vinegar. Rice, which is a grain, ferments to rice wine, known as sake. (Technically, it would be in the beer category since it is a grain.) Sake becomes rice wine vinegar.
     So, here is the chemical reaction...  The first fermentation occurs when yeast metabolizes sugar into alcohol. The second spoilage takes place when bacteria metabolizes alcohol into acetic acid.
Isn't that just the coolest science lesson, ever?
      The bottom line is... "Vinegar has spoiled so much that it will never spoil again. It will keep at room temperature in a closed bottle indefinitely until it evaporates."
     In history, vinegar has been used as a medicine, a corrosive agent, and as a preservative.  The word is from the French vin (wine) and aigre (sour.) If you need a great basic vinaigrette recipe, check out my post on the subject!
Tune in next time when we study the mold properties of bread... a question posed to me by The Housewife is the inspiration for our discussion.

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