As a follow up to your post regarding oats not being chametz, could you please list the 5 grains that are Chametz. I’m assuming that wheat, barley, rye and spelt are 4, but what would be the fifth?
Also, I have a cannister of 365 Whole Foods Market Organic Quick Oats (rolled oats) that lists Organic rolled oats under ingredients, but then says under it “may contain wheat.” Would this be ‘batul beshishim’ or make it not kosher for passover?
Thank you.
Aaron Abadi 
michael aryeh
We don’t really know the specific 5 grains, other than wheat and barley.
Spelt and rye fit into the mix, but we don’t have evidence that they’re their own grain category as opposed to under the umbrella of wheat.
The way we got the current 5 grain list is because some people decided we need to identify five different grains, so they took the liberty of choosing what they thought might fit.
They saw a Rashi that said “oats” bela”az, so they ran with it. This is extremely dishonest and not how our Torah works. Rashi didn’t speak English and whatever oats meant to him, has no bearing on the product we call oats.
As far as the “may contain wheat” issue, ignore it. That’s just an allergy disclaimer. You never found wheat in your oatmeal and you never will.