Pretty much any time I bring this up this next subject with anyone I end up in a useless argument. Let's start simply by understanding that I am right. I studied up on it when I was pregnant with my daughter and done too much research on it to be convinced otherwise.
The subject in question is how much alcohol cooks off in food preparation. For most of my life I've heard that the alcohol cooks off because its boiling point is lower than that of water and it evaporates more easily. That always seemed like a strong bit of chemistry that served as good proof. Too bad it's wrong.
Want more chemistry? Water and alcohol have an affinity for each other and form an azeotropic mixture. So when the vapor burns off it burns off in the same ratio of alcohol to water that it was mixed at. The alcohol does not burn off first and will not be entirely gone until all the liquid has boiled off. That was news to me.
Talking about it in terms of chemistry seems theoretical when compared with lab experiments that actually test the alcohol content after a certain cooking method has been employed. The short version of it can be seen in chart form here (go to the question at the bottom of the page), or any number of other sites if you do an internet search for it. The chart was translated over from the USDA Table of Nutrient Retention Factors, Release 5 (2003) and is much more useful and interesting than the 205 pages of information from the USDA(the pertinent alcohol content stuff starts on page 125, if you're actually that interested in looking at it straight from the source). I couldn't get the chart to copy nicely, so just go to the chart for a second and I'll wait for you to come back...
Were you surprised? I always assumed that a flambe was the best method of getting rid of the alcohol, but it leaves 75% behind. I'm kind of a hardliner about making sure I consume no alcohol, so this was good stuff for me to learn.
On the plus side for me, it gives me another reason to politely decline anything cooked in alcohol. One reason I never ate it before was because of the taste. Blech. In Italy I was served a beef dish that had a really funky taste to it. I choked it down, wondering all the time what had been done to make a cow taste bad (I love pretty much any form of beef). After the meal was over our hostess told us that she'd cooked the meat in champagne, but not to worry because all the alcohol cooks off and just leaves a wonderful flavor. In my opinion, pretty much anything that is fermented before it is consumed is just nasty. I'm sure somewhere out there exists something fermented that I like, but I can't think of anything.