We've encountered recipes which finish tomato sauce with a pinch of baking soda. Will this mellow out a sauce that is too acidic?
An important factor in achieving great tomato flavor is balancing acidity and sweetness. Too much of either can leave you with a tomato sauce that tastes one-dimensional. Adding baking soda will change the pH of tomato sauce, making it less acidic. Generally, we balance tomato sauce acidity by adding a bit of sugar. While sugar can’t neutralize acidity in the same way that baking soda can, it does change our perception of other tastes.
We made a giant batch of our Quick Tomato Sauce recipe, divided it into 3-cup samples, and spiked some with either sugar or baking soda. The sample enhanced with just ¼ teaspoon of sugar tasted bright, balanced, and more intense in tomato flavor, while the sample with an equal amount of baking soda was deemed flat and solely sweet. When we scaled back the baking soda to 1/8 teaspoon, tasters found it closer to the sugar-adjusted sauce but still not as complex.
Bottom Line: We will continue to reach for sugar (add ¼ teaspoon at a time until the desired flavor is reached) to balance our sauces and enhance their complexity.