Antioxidants in baking

we are in the process of exploring the possibility of adding ascorbic acid to our cracker recipe to help with shelf life and combat rancidity and off-flavor. I read that the antioxidant should not exceed .02% of the oils in the food. Is this true? I am trying to figure out how much ascorbic acid should be added to the dough. 

Upon more research a different antioxidant could suite us better, anyone have any ideas?

We're in the process of exploring rosemary extract and tocopherols (vitamin E) for granola. I'm curious to see what others have to say on this topic. 

Interesting topic.  Have you called the AIB (American Institute of Baking)? They might be able to help or point you in the right direction.