natural flavors again

Question

Thanks for your two answers regarding trace ingredients. However, I've seen you write that natural flavors mixed into a product are okay even if they are unkosher; I assume b/c they are batul. But they are put there to give flavor to the product, so doesn't it stand to reason that their flavor is still being tasted, and, if the flavor is unkosher, shouldn't that cause the product to be unkosher? If that's correct, why don't we have to worry about cases where the natural flavors are not identified? Maybe they are unkosher. Thank you.