How to Make Tomato Sauce Less Acidic | Cook's Illustrated (2024)

There’s nothing quite like a perfect ripe tomato. As many as 400 compounds come together to form the flavors and aromas we recognize as tomato-y, allowing it to taste sweet, tart, savory, and a little bitter all at once.

But peak tomato ripeness is elusive, and the flavors on either side of it tend to swing noticeably acidic as the fruit’s sugar content is still ramping up or beginning to drop off if left on the vine too long. It’s not always so noticeable when you’re piling sliced tomatoes on BLTs or dressing them in a salad, but you can really taste the tartness when you cook down a big pot of them for pasta or pizza sauce.

Luckily, there are numerous ways to tone down that sharpness. We tested two of the easiest and most common approaches (adding sugar or baking soda) to see if we liked one better than the other.

But before we get to those results, let’s take a closer look at tomato flavor and how some tomatoes wind up tasting more tart than others.

Fresh ripe tomatoes contain from 0.3 to 0.6 percent acid: primarily citric, malic, and ascorbic acid. While tomatoes can have more or less of these acids, most varieties (even those that are purportedly low acid) generally fall within the same relatively narrow range.

Another important factor in determining how tart a tomato tastes is its overall balance of flavors and aromas, particularly sweetness.

While some tomatoes have been bred to have more glucose and fructose, generally, the riper the tomato (up to a point) the sweeter it will taste, due to the development of sugar during the ripening process.

By the same token, underripe tomatoes taste more tart since they lack some of the sweetness that would otherwise offset their acidity. (And after a tomato is past its prime of ripeness, its sugar level drops.)

The lesson: For a tomato sauce that tastes less acidic from the get-go, use only ripe tomatoes from your backyard or the farmer’s market, or a canned brand that doesn’t include added citric acid, which can increase tartness. (Our favorite canned tomato, Cento San Marzano Certified Peeled Tomatoes, has no added citric acid and produced a sauce tasters described as “bright, fresh, and sweet.”)

TESTING SUGAR VS. BAKING SODA: WHICH DOES A BETTER JOB OF TONING DOWN TARTNESS?

To determine whether adding sugar or baking soda is more effective in reducing acidity in tomato sauce, we made a giant batch of our Quick Tomato Sauce, divided it into 3-cup samples, spiked some with either sugar or baking soda, and then tasted each side by side.

Both ingredients altered the tart taste of the sauce. But 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 a little flat in comparison, with a more one-dimensional sweetness, even when we scaled down the amount to ⅛ teaspoon.

OTHER WAYS TO TAME TARTNESS IN TOMATO SAUCE: ADD CREAM OR BUTTER

Cream and butter will also tone down acidity in tomato sauce, but like baking soda, they can have downsides.