Just a thought about human grade food. There is no such thing (that is, it is undefined by any organization that dog food companies need to follow).
While browsing YT, I found this thread:
http://www.yorkietalk.com/forums/yor...enaturant.html
and it looks like a bunch of YT'ers are looking for human grade food. The problem is, that phrase can mean nothing at all. Food is either "fit" or "unfit" for human consumption. If a dog food company will not tell you that all of their ingredients are fit for human consumption, then they probably aren't. That isn't to say that it is wrong to feed a food that isn't fit for human consumption, but I know there are people here who would only feed a food if they could eat it themselves and human grade does not mean that you can. Of course it also doesn't mean that a company that uses the term "human grade" is using ingredients unfit for human consumption either. Each company would have to be asked...
Here is a page from a veterinary nutritionist's site (see last paragraph):
https://www.petdiets.com/faqs/display_faq.asp?ID=774