I think its wheat for me even in very small amounts. There is a diet call Virgin diet. Basically you stop all regular food and buy their shakes, drink only that for 7 days (600 cal) and introduce food types , dairy one week, grains next etc to find out which type of food you are allergic to. One of my friends found out she is slightly allergic to wheat which surprised her. I am happy to avoid wheat and move onto other things now.
Thanks for your reply.