How To Substitute Ketchup For Tomato Sauce

We've all been in an ingredient bind in the kitchen before. Maybe the stores are closed or you simply don't want to make another trip, but you need that one ingredient to ensure the recipe is a success. In baking, you can use pumpkin puree instead of applesauce or ground seeds instead of eggs, and whatever dish you're making should turn out just fine. In the savory department, tomato soup can be used as tomato sauce, as can — surprise — ketchup. 

Out of all the tomato-derived ingredients, ketchup is, admittedly, an unlikely replacement for tomato sauce — it's seemingly much too sweet and vinegary. Ketchup can take some adjusting to replace tomato sauce and it's not the perfect fit for every recipe, but it is a convenient ingredient that many of us happen to have in the fridge. Plus, many tomato-based recipes do call for sweet and savory components, such as pizza sauce, BBQ sauce, and Sloppy Joe's, to name a few. Although these are certainly considered to be savory recipes, something sweet, such as sugar or molasses, is called for to enhance the spices and other flavors present. In recipes with a little sweetness such as these, ketchup would work really well to replace tomato sauce.

To understand how to use ketchup as a replacement for tomato sauce, we need to break down what exactly ketchup is comprised of. The main ingredients of ketchup are typically tomato concentrate or tomato paste, with vinegar, some type of sugar, and a blend of salt and spices. The ratios and ingredients change slightly based on the brand, with one of the biggest changes from brand to brand being the sugar content; brands with less sugar are usually better. 

In general, ketchup can be used as a 1:1 replacement for tomato sauce, though you wouldn't want to serve a plate of spaghetti and just squirt ketchup on top. However, with a few adjustments, ketchup can certainly be used to make a pasta sauce. The sugar in ketchup can be balanced with other ingredients by adding herbs such as basil, oregano, and thyme, and aromatics such as onion and garlic. Olive oil is also a good addition for sauces, and vegetable or chicken stock is a good way to balance ketchup in a soup, stew, or chili recipe. For dishes that call for a small amount of tomato sauce, say a tablespoon or so, there isn't much need to greatly alter the sauce. Chances are there are plenty of other savory or salty components already present in the recipe to help balance the ketchup.