Some of you might know a little about a book that was "bible" of professional cooks in the 80's, On Foods and Cooking- The Science and Lore of the Kitchen by Harold McGee. (He's come out with a new book but its not as informational, in my opinion). Although he does not spend as much time on butchering animals and hanging carcasses as I thought he would, he does explain a few things. You might see if your local library caries the book to read verbatum or here is my intepretation of major points:
1) Stressfull dispatching is to be avoided. A muscle works by "feeding" off of latic acid reserves. If an animal is over worked, stress of shipping, handling, fleeing, it uses up these reserves and is forced to quickly break down the muscle for fuel, producing a bad texture in the final product. He talks about how the color of the meat can acutally be darker from this stress which makes me think of how "endurance" muscle fibers are dark & thin and "strenght" muscle fibers are white & round.
2) Rigormortis passes in 6 hours for the chicken.
3) Hang carcasses. The muscel fibers are forced to relax or cannot contract as they would otherwise (this is not rigormortis) and thus improves texture.
4) Aging of all meats produces a better texture. As the cell walls begin to break down, it releases the bodies own enzymes, used for digestion within the cell, which begin to gradually break down the muscle fibers.
5) Keeping meats dry helps to inhibit bacterial growth.
6) Temperatures below 38 degrees also inhibits bacterial growth.