It’s hard to say anything negative about America’s favorite condiment: ketchup. This simple combination of tomatoes, sugar, vinegar and spices creates a sweet-and-tangy sauce that’s perfect for dipping french fries, making barbecue sauce or glazing meatloaf. Unfortunately, store-bought ketchup is a hidden source of sugar. Every tablespoon serving of Heinz ketchup may contain only 20 calories, but it has 7% of your daily sodium and 4 grams of sugar. What if we could change all that by making a low-carb, sugar-free ketchup at home?
It’s easier than you think. You’ll only need an onion, a handful of fresh or canned tomatoes, a bunch of spices and some vinegar. Of course, there are some great sugar-free options out there if you don’t have time to make ketchup from scratch. Heinz makes a fantastic “no sugar added” version of their classic ketchup, but we also like the ones made by Primal Kitchen and G Hughes.
How to Make Sugar-Free Ketchup
- 1 tablespoon olive oil
- 1 medium onion, chopped
- 3 pounds tomatoes (or, a drained 28-ounce can plum tomatoes), coarsely chopped
- 1 cinnamon stick (3 inches)
- 3/4 teaspoon celery seed
- 1/2 teaspoon mustard seed
- 1/4 teaspoon whole allspice
- 3/4 teaspoon kosher salt
- 1/4 cup red wine vinegar
- 1-1/2 teaspoons smoked paprika
Yield: 1 cup
Editor’s Tip: If tomatoes are in season, this recipe is a great way to preserve the harvest! Otherwise, we’d recommend using canned tomatoes, which are packed at the peak of freshness.
Step 1: Cook the ketchup base
Since we’re not adding any sugar, you’ll want to add natural sweetness to the ketchup by caramelizing the onion. In a large saucepan, heat the oil over medium-high heat. Add the onion and cook until it’s golden brown and softened, about 10 to 15 minutes.
If you’re using canned tomatoes, add them to the onion and cook for a minute until they’re warmed through. For fresh tomatoes, cook the mixture, uncovered, for about 25 minutes, until the tomatoes are tender and soft.
Step 2: Press out the solids
One of the defining characteristics of ketchup is its smooth texture. You don’t need any special equipment to get there—a fine mesh strainer works just fine! Press the tomato mixture through the strainer and discard the solids. Return the mixture to the pot and bring it to a boil. Reduce the heat to a simmer and cook, uncovered and stirring frequently, until the liquid is reduced to about 1-1/2 cups, about 10 minutes.
Editor’s Tip: Fresh tomatoes tend to clog up the strainer faster than canned ones. Consider pressing the sauce in batches, which gives you a chance to clean out the seeds and skins that cause clogs. If you’re short on time, use a food mill like this instead.
Step 3: Infuse and reduce
Now that your tomato mixture is thickened and oh-so-smooth, it’s time to infuse some flavor into your homemade ketchup. We recommend wrapping the cinnamon, celery seed, mustard seed and allspice in cheesecloth to prevent them from ending up in the finished product. Place the spices on a double thickness of cheesecloth, gather the corners of the cloth to enclose them and tie the pouch securely with a piece of kitchen twine.
Add the spice pouch to the tomatoes along with the salt and return the mixture to a boil. Reduce the heat to a simmer and cook, uncovered, for 20 to 25 minutes.
Editor’s Tip: Be sure to stir the ketchup frequently during any simmering steps. Although we haven’t added any sugar, the tomatoes have plenty of natural sugars that can burn.
Step 4: Finish it up
By this point, the ketchup should be nice and thick. Stir in the vinegar and smoked paprika, and simmer the ketchup until it reaches the desired consistency. Discard the spice bag and transfer the ketchup to a storage container. Let it cool slightly before covering it and storing it in the refrigerator.
The ketchup lasts about a week in the fridge, so don’t double the recipe unless you plan to eat a lot of ketchup this week!
Honestly, I didn’t miss the sugar at all. This ketchup had plenty of sweetness on its own from the caramelized onions and reduced tomatoes. The vinegar gave it the right amount of acidic tang, and the smoked paprika provided a real depth of flavor. Plus, the whole thing was so easy to make, I may never buy store-bought ketchup again!
This sauce isn’t just for dipping french fries and chicken tenders. Give your sugar-free ketchup recipe a whirl with these recipes to make with ketchup.