Does anyone else have a violent reaction to shredded cheese?

This is going to sound crazy but follow through with me.

I eat a lot of burritos that I make at home and I am really lazy. So I buy pre-shredded cheese.

Specifically this. Actually, Tillamook switched things up about four months ago and now only sells the “Farm Style Cut” shredded. They used to sell a finely shredded medium cheddar.

I hate the “Farm cut” and this is what led to my discovery.

So I have been buying the pre-shredded stuff for a few years and after a few bites it always gave me heartburn. Sometimes to the point of vomiting. (20% vomit) But I would eat a few bites and clutch my chest for a few minutes and maybe vomit and then continue eating. For some reason I was okay with this. I wasn’t sure why it happened and I didn’t really care.

So when Tillamook went with the farm cut thing I switched to the Safeway brand of shredded cheese. Then I noticed no more painful chest-clutching or vomiting.

So I tested. With this no pain. Shredded by hand.

Cultured Milk, Salt, Enzymes, Annatto (color).

Here is the shredded of what should be the same cheese.

Cultured Milk, Salt, Enzymes, Annatto (color), Potato Starch (added to prevent caking), Natamycin (natural mold inhibitor).

So something is going on here with the two extra ingredients.

Any idea why “Potato Starch” or “Natamycin” would cause such a violent reaction in my body? And am I alone in being having such a reaction?