I'll start this with a little info on what to avoid (scroll down, there's a nice list):
http://withstyle.me/2011/09/13/celiac-awareness-living-gluten-free/
http://withstyle.me/2011/09/13/celiac-awareness-living-gluten-free/
So Diedra are frozen vegetable gluten free? And I read somewhere the other day if we have to use canned vegetables it is best to pour their juices off & rinse them.
Frozen and canned veggies are gluten free as long as there is not any added spices or sauces. I never rinse my canned veggies. One could if you wanted. I have know someone (not gluten free) who always rinses her canned beans and I never do.