Most old-fashioned recipes for tomato soup from the United States do not feature turmeric, or indeed, many other spices. The flavor is created by cooking fresh, ripe tomatoes carefully with a minimum of other ingredients, generally including dairy produce at the latter stages of preparing the dish.
Ground black pepper is the only spice regularly used in traditional tomato soup recipes, though some recipes do call for a little fresh chopped parsley. Many recipes also call for a little baking soda to retain the color of the tomatoes. For those who would prefer more spice, a non-traditional but delicious recipe for turmeric and tomato soup can be found at InstinctiveHealth.co.uk.