how can I reduce the acidity of a tomato vegetable soup?
the tomatoes were extremely acidic.
A tiny pinch of sugar should do the trick. And if one pinch isn't even, add a second, but taste carefully after each addition, as it is easy to overdo it. A touch of cream also will help smooth it out nicely.
Sorry, that should have been "isn't enough." Really must read my answers before submitting . . . . ;o)
I would go with the cream (or milk) answer but in proportion to the soup. Don't overwhelm it. Depending on where you live you might be able to buy Mexican crema cf. creme fraice, sour cream etc. That would work too.
Try some "sweet" veggies. . . .carrots always help take the acidic edge off tomatoes.
Sugar, wine, or a little cream should do the trick. Also, sometimes canned tomatoes just need to simmer for a while to get their natural sugars in action. Try simmering for a while (add some extra broth or water), and then try adding another ingredient.
A pinch of baking soda.