Disappearing Vitamin C

How can you have a soup whose first ingredient (after water) is potatoes, but it has no vitamin C? How can you have spaghetti and meatballs with no vitamins? How can you have something with the ingredients mango pulp, sugar, and ascorbic acid and still have no vitamin C?

In America, we process all the vitamins out of the food and then put them into pills. When I notice that I am eating one of these vitamin-free foods, I eat a vitamin pill with it, but I'm going to try not to buy those anymore.

Protein seems immune to processing. That's something at least.