Making and canning tomato paste: A step-by-step guide
Updated: Sep 27
Making and canning your own tomato paste at home might seem like a daunting task, but it’s a rewarding process that not only gives you a product that’s free of preservatives and additives but also allows you to fully control the flavors. In this post, I’ll show you exactly how I make it, step by step ;)
Why make your own tomato paste?
Tomato paste is a pantry staple used in a variety of recipes, from soups and sauces to marinades and stews. Making your own paste means you can use garden-fresh tomatoes at their peak and avoid the metallic taste that some store-bought cans have. Plus, it’s a great way to reduce waste and save money in the long run!
What you’ll need
Ingredients
12 pounds ripe Roma or other paste tomatoes (mine are mostly Roma from the garden)
1 tablespoon salt (optional)
4 tablespoons bottled lemon juice (or 1 teaspoon citric acid)
Makes about 4 four-ounce jars.
This is the tested Roasted Tomato Paste recipe from The All New Ball Book of Canning and Preserving.
Equipment
Large baking sheets
Food processor
Large bowl and a large spoon
4-ounce mason jars with new two-piece lids and bands
Water bath canner with a rack
Jar lifter
How I make and can tomato paste
1. Prepare the tomatoes
Start by washing your tomatoes thoroughly. Core them, cut them in half and scoop out the seeds.
2. Roast the tomatoes
Lay the tomato halves cut side down on baking sheets in a single layer and roast them in a 175°C (350°F) oven until the skins are wrinkly and just starting to char. Let them cool until you can handle them, then pinch off the skins.
3. Purée the tomatoes and add the acid
Purée the tomatoes in a food processor until smooth. Pour the purée into a bowl and stir in the salt, if you’re using it, and the bottled lemon juice (or citric acid). The acid goes into the purée now, before it goes back in the oven, so it mixes in evenly.
4. Cook it down in the oven
Spread the purée on one baking sheet and put it back in the oven at 175°C (350°F). Stir it every 20 to 30 minutes (and re-flatten it on the sheet), paying extra attention to the edges. You really don’t want the paste to start to stick to the sheet. It’s ready when it’s very thick and dark red.
5. Get the jars ready
While the paste is in the oven, wash your 4-ounce jars and keep them hot until you fill them. Get your new lids and bands ready, too.
6. Fill the jars
Spoon the hot tomato paste into the hot jars, leaving ¼ inch of headspace. Remove any air bubbles with a non-metallic utensil, add more paste if needed, and wipe the rims with a clean, damp cloth. Place the lids on and screw the bands on fingertip-tight.
7. Process in a water bath
Place the filled jars on a rack in your water bath canner with at least 1 inch of water over the tops. Bring it to a rolling boil and then start the timer: 45 minutes if you’re between 1,001 and 3,000 feet (I’m at 2,273 feet, so 45 minutes it is). Below 1,000 feet it’s 40 minutes, and above 3,000 feet it’s longer, so check my altitude chart.
8. Cool and store
Turn off the heat, take the lid off the canner and let the jars sit in the water for 5 minutes. Then lift them out with a jar lifter onto a towel on the counter and let them cool undisturbed for 12–24 hours, then check the seals. Take the bands off, then store the jars in a cool, dark place. For the best flavor, use them within a year. Any jar that didn’t seal goes in the fridge, and so does an open jar.
Label your jars with the date, too.
Happy canning!
Making and canning your own tomato paste is a satisfying project that can help you get the most out of your tomato harvest. The result is a versatile and delicious product that’s ready to be used in your favorite recipes throughout the year.
More from my tomato harvest: my Italian passata and homemade pizza sauce ;)
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