What are the physical and chemical changes that occur when making sausage stuffing?

Question

the recipe is:

sausage

eggs

bread crumbs

celery

onions

butter

Cook sausage. Take out the sausage and leave the grease in the pan. Saute diced onions and celery in the leftover sausage grease. Melt butter in microwave. Beat the eggs in a bowl.

Pour melted butter over the bread crumbs which makes them moist. Combine bread crumbs, cooked sausage, beaten eggs, onions and celery and put inside the turkey. The turkey juices during the cooking process, flavors the dressing and makes it moist.

Answer 1

Tough one.  Dicing veggies is physical.  I believe cooking is chemical, as is beating the eggs.

Answer 2

Do a search on Food Science: Cooking the sausage denatures the proteins thus causing it to release moisture; maillard reaction. Cooking celeries causes an osmosis action (?). I think cooking onions would be a maillard reaction aswell. Beating eggs in a bowl causes air to be incorporated into it.

I know of a really good book called "The Science of Food and Cooking"; it's been around for years, though I can't remember the author.