Because of the corn allergy, I am severely limited in what brands of dairy products I can use. For instance, most, if not all major brands of yogurt have either cornstarch, corn syrup, or both. I can find the organic brands that don't contain corn products pretty reasonably at our local warehouse-type store. They also carry the Western Family Naturals brand of sour cream-most sour creams have cornstarch, but this particular one doesn't. I just have to be sure to read the label and get the natural one. I was across town today and wasn't planning to go to the warehouse store, but here's what I found in Walmart:
No corn starch-just milk products! (I'm lucky enough not to be allergic to milk)
Another shopping problem I had was powdered sugar. They add just a bit of cornstarch just to keep the sugar from caking. Consequently I haven't had frosting since May. This is what I found in the local Food Co-op:
Instead of cornstarch, they use tapioca starch. Frosting here I come-provided I can put together a decent cake with my special flours.