Said Bismillah before a haram meal

My friend bought marmalade that didn't have gelatin in it. (We both checked it) I ate some marmalade and said Bismillah beforehand. Later I found out that these marmalades had carmine in them, which is haram. I read on a website that if you say Bismillah and eat haram food, it is an act of disbelief. Is this true? Do I have to make tawbah for kufr? And is it kufr if by ignorance I call haram halal and vice versa?