GB said:
In most cases this is not true.
Here is a chart that will show you how much alcohol is actually left after cooking. You would be surprised at the amounts.
GB makes a good point, but there is one other thing to keep in mind when looking at those numbers - That's the percentage of ALCOHOL that remains.
On average, a cup of wine will only be about 12-14% alcohol by volume. So you end up looking at a percentage of a relatively small amount in most cases.
I bring this up because whenever this issue comes up, sometimes people forget to look at just why they're looking for alternatives. If you are seeking to avoid all alcohol, then this would be an issue. If you need to limit it, it may not be. If you have health concerns, it's probably best to ask your doctor.
Just one last footnote, if you really are looking to avoid all alcohol, make sure to avoid anything that uses active yeast (yes, I'm being serious). Yeast consume sugars and give off carbon dioxide and alcohol. So when your bread or doug rises, there are amounts of alcohol being created. Yes, this is taking it to the extreme, but I only mention it as a datapoint..
(What, y'all didn't think I had up and left, did ya?)
John