HP baked beans do NOT contain gluten - it clearly states this on the tin. As for other brands its very difficult to tell. Some use a thickening agent in the tomato sauce which could possibly contain...
The "bean" is the seed, however it is not really a bean. In this seed, there is ricin, a deadly toxin. The lethal dose for adults is 4 to 8 seeds, however reports of poisoning are relatively rare....
Wheat contains gluten but rye and barley also contain gluten. Gluten is a protein found in grains. People with Celiac's disease are allergic to wheat and gluten. Tapioca and spelt are examples of...