Many packaged foods taste moldy to me but not to others. I return some products but the stores are acting like I am trying to rip them off. There are several mold test kits for homes and air. Will these detect mold in packaged foods? Recently I got a moldy taste in Vitamin C gummies and dairy-free chocolate chips. These were not expired but I could not even swallow them because of the mold taste. Does packaged food look okay but taste moldy to you?
A household mold test is going to test for the sort of mold which causes problems for buildings. It's a very different organism than that found in food.
The main thing you need to consider is whether you know what mold tastes like. Spoiled food will taste strange in many different ways, so if you're associating what you're tasting with a moldy food you had, you might be recognizing something completely different.
It strikes me that vitamin gums and chocolate chips are both at least somewhat likely to be coated with a small amount of cornstarch to prevent sticking. You should look at the ingredient labels and see if that, or some other ingredient, is common to them. I've heard of people who dislike the taste of cornstarch.