Tomato Jam: Ketchup’s Classy Cousin

A simple homemade tomato jam recipe that transforms fresh summer tomatoes into a sweet and savory condiment

San Marzano Tomato Jam © 2026 TDWolsey

I have a confession to make. I’m a ketchup snob. I only put it on fries, burgers, and hot dogs — and even then, if there’s an alternative, I’ll usually take it. One of my favorite alternatives is homemade tomato jam.

Tomatoes are the star of many summer gardens. Like other fruits that masquerade as vegetables, they make a fantastic jam. In past articles, we’ve made onion jam and red pepper jam; you’ll find those links below.

Anything you can do with ketchup, you can do with tomato jam. It’s just that tomato jam does it so much better. Ketchup is typically made from tomato paste and relies heavily on vinegar, sugar, and salt for its characteristic flavor and long shelf life. That’s why restaurants can leave it out on tables for days at a time. On the other hand, tomato jam is made from fresh, diced tomatoes, and it gets its flavor from the combination of tomato with warm spices like cumin, ginger, and cinnamon.

Unlike ketchup, tomato jam belongs to the same family of preserves as peach jam, strawberry jam, and marmalade. That started me thinking about the jams my mother used to make when I was growing up.

Mom Always Added Pectin

When I was a kid, Mom made jams and jellies from all kinds of fruits. We always had strawberry jam in the freezer, apricot and peach jam in jars, and of course, grape jelly. All homemade. To every one of those preserves, we added pectin to thicken the final product.

Pectin is a natural, soluble polysaccharide found in the cell walls of fruit. It provides structure to the fruit, so you’ll find it concentrated in fruit cores and skins or peels. It’s this support aspect of pectin that makes it ideal to firm up many preserves.

You could add a tablespoon or two of liquid pectin if you want to speed up the process, but our tomato jam gets its pectin from citrus and from the tomatoes themselves. Tomatoes, like all fruit, contain some pectin, and we’ll simmer them slowly until we have the consistency we want. For red tomato jam, we’ll use meaty tomatoes like San Marzano, Roma, or other plum-type tomatoes to keep the jammy consistency we seek.

How To Make Homemade Tomato Jam (It’s Easy!)

While plum-type tomatoes are ideal for jam due to their meaty texture, other kinds of tomatoes also make excellent jam. While researching this article, I found several jam recipes for end-of-season unripe green tomatoes. I’ve never tried these, but if you do, post a note in the comments with your thoughts.

Some green tomatoes stay green even when fully ripe, and others come in beautiful colors that hint at their flavor. Those colors also give us a clue about the taste. Green Zebra tomatoes make a wonderfully tangy jam, so I’ll put the ingredients for my version of green tomato jam below. You can add a jalapeño to both versions for a slightly more picante version, or you can leave it out.

Ingredients for Red Tomato Jam

• 1 pound plum or Roma tomatoes, cored and cut into 1-inch pieces
• 3/4 cup granulated sugar
• 1 tablespoon apple cider vinegar
• 1 tablespoon fresh lemon juice
• 1 tablespoon grated peeled fresh ginger
• 1 teaspoon kosher salt
• ½ teaspoon ground cumin
• ½ teaspoon cinnamon
• ¼ teaspoon smoked paprika
• ½ teaspoon dried thyme
• ¼ teaspoon red pepper flakes
• 1 jalapeño (optional, pickled jalapeños also work)

Directions for Red or Green Tomato Jam

1. Place all of the ingredients in a heavy-bottomed saucepan. Bring it to a boil over medium-high heat, stirring frequently.
2. Once the mixture begins to boil, reduce the heat to low. Let the mixture simmer, stirring occasionally. Once the jam reaches the consistency you prefer, remove it from the heat, and let it cool. For a traditional jam consistency, many cooks aim for approximately 220°F (104°C), though texture ultimately matters more than the thermometer reading.
3. The recipe above made one cup. If you are going to store the jam in jars using a water bath, you can increase the ingredients to make more. Be sure to follow canning advice; botulism is no one’s friend.

The jam you see in the photo above simmered for an hour and fifteen minutes. Depending on the heat setting and the amount of water, the jam might take longer. Just keep an eye on it.

San Marzano Tomatoes © 2026 TDWolsey

Ingredients for Green Tomato Jam

Look for small to medium-sized green tomatoes; they will be less watery than larger tomatoes. In this recipe, I left out the vinegar and used more citrus juice to keep it tangy.

• 1-pound Green Zebra tomatoes, cored and cut into 1-inch pieces
• 3/4 cup granulated sugar
• 2 tablespoons fresh lime juice
• Zest of one lime
• Several sprigs of cilantro, chopped (about ¼ cup; you can use basil in place of cilantro)
• 1 tablespoon grated & peeled fresh ginger
• 1 teaspoon kosher salt
• ½ teaspoon ground cumin
• ¼ teaspoon red pepper flakes
• 1 jalapeño (optional)

Depending on temperature and water content, this jam could simmer for up to two hours.

Add your jam to cheese and crackers. Add it as a glaze to flank steak, roasted chicken, or grilled vegetables. Tomato jam accompanies turkey sandwiches beautifully. For any food where you might use ketchup, like a burger or fries, class it up with tomato jam instead. Try it in crepes for a sophisticated but easy breakfast.

Imagine toasted rustic-style bread with a thin layer of mayonnaise, a lettuce leaf and thin-sliced tomato, a couple of slices of turkey piled on, and another slice of toasted bread. Piled on that, crispy bacon and more turkey. On top of it all, just before placing that last slice of bread and securing it all with a cocktail skewer, spread elegantly at the last step is rich, tangy tomato jam.

I have to go to the kitchen now and make a sandwich. I’m hungry, but the ketchup bottle can stay exactly where it belongs: unopened.

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