I had an episode like that. Produce skins, like apple and tomato, also were a trigger. I only have three ideas: (1) try avoiding tough veggie/fruit skins and/or seeds. But as it seems you can normally eat most of what you want, (2) you could have a tipping point, where some of what you added back into your diet is fine, up to a point, but beyond that amount, you get an attack, or (3) some of what you added back into your diet can't be "chewed up" so goes in whole, more or less (as a side note, corn is hard for any number of people to digest due to its cellulose component; humans don't have an enzyme to digest it.)