Hey oh
LOL, you were in my kitchen on Saturday weren't you!!!
I use tumeric as a colourant all the time. In doughs, pastas, and rices. I also use paprika for a nice dull earthy red. Food colourings are too much temptation for the kids to get into, and I like the natural colourations better.
I can't see the price being a factor though. Isn't tumeric actually cheeper?
Oh, and about a tablespoon per 2 pounds flour if your interested.
I do want to try the extended rise and see if the beer taste holds true.