Canning Tomato Soup Base

Follow this step-by-step tutorial to learn how easy canning tomato soup base can be. The ultimate comfort food, this homemade canned tomato soup base recipe can be pressure canned or preserved via water bath canning. 

Homemade tomato soup is amazing and tastes so fresh, but peeling and pureeing tomatoes each time you want soup is super time-consuming. Not to mention that tomato season is only about six weeks long in most climates.

So what is a soup-obsessed girl to do? Can her own tomato soup base, of course. Let’s do this!

How to Pressure Can Tomato Soup – Step by Step

I’ll walk you through the process here in photos because it really helps, especially if you’re new to canning. At the bottom of the post, you’ll also find a printable and detailed recipe card.

Rinse all your awesome tomatoes and cut them in half. If you have big ol’ tomato chonkers, then cut them into smaller chunks. Add a strainer/colander to a large bowl.

Wash and clean your jars. For canning soup, I recommend quart-sized regular-mouth jars. It is no longer necessary to sterilize jars before canning (hurray!), but you should make sure they are preheated enough to not crack when placed in hot water.

You can put them in a clean dishwasher and run them through a quick wash cycle, or place them in a large pan with some water in a low-heat oven (my lowest temp is 170˚F) until you need them. I’ve even just put super-hot tap water in them before and left them on the counter.

Wash your lids with hot soapy water and place them in a clean bowl for now.

I save canning tomato soup for the end of the season when all that is left are the random tomatoes. Random tomatoes make the best soup because you get all the complex, amazing tomatoey flavor in one delicious bowl.

You need about 45 pounds of tomatoes for 14 pints or 7 quarts. Since I never have that many at once, I do small batch canning and might produce 1-4 quarts at a time. It all adds up, and it all eats the same.

Add the tomatoes to a pot of boiling water and parboil them until you see the skins start to come off one of the tomatoes (about 1-2 minutes).

Use a slotted spoon and remove the tomatoes and place them in the strainer.

Run the tomatoes through a food mill to remove the seeds and skins. If my tomatoes are particularly watery, I will strain them a bit through a mesh strainer. 

Transfer the tomato puree to a pot over low heat or a crockpot set to low. Keep warm until ready to can.

Add 3 quarts of water to your canner and put it on a burner set to high. Make sure there is a canning rack in the bottom of the canner. (Reminder: these are pressure canning instructions. See the instructions below and in the recipe card for water bath canning details).

Place a funnel on a canning jar, add the lemon juice or citric acid, and ladle in the warm tomato puree, leaving 1 inch of headspace. Remove any bubbles from the jar (I use a plastic chopstick).

The lemon juice is needed to regulate the acidity of the tomatoes to keep the pH level consistent. Store-bought lemon juice generally has the same level of acidity (5%) from bottle to bottle.

Use a wet, clean rag and wipe the rim of the jars to make sure they are free of any food.

Place a clean lid and then a ring on the jar and tighten the ring to fingertip tight (tight enough that it won’t come off, but not so tight that the Hulk couldn’t budge it).

Using canning tongs, place the jars in the canner. Lock the lid. Soon, steam will start coming through the vent pipe (I call it the steam chimney). Allow the steam to pass through for about 10 minutes. Then put the pressure regulator (I call it the chimney cap) on top.

Pretty soon, the air vent will pop up. That is a sign that you’re starting to build pressure inside the canner. Get excited, nerd!

Under normal conditions, tomato soup needs to be pressure canned at 11 pounds of pressure for 15 minutes for both pints and quarts. See the chart below for any changes to processing times.

When the dial gauge reaches the appropriate PSI, reduce the burner temp to medium, and start your timer. The pressure must stay at the PSA or (a little bit) above for the duration of the cooking time.  You’ll likely need to adjust the temp on the burner a few times, depending on your stove.

When the time is up, remove the canner from the burner and allow it to sit until you hear a distinctive “click” of the air vent dropping. Remove the pressure regulator and carefully remove the lid of the canner (Pro tip: I always use oven mitts when I take the lid off because the steam is super hot). Let the jars sit in the canner with the lid off for 5 minutes.

Place hot jars on a towel where they can sit undisturbed for 12 hours.

After a few hours, to check for sealing, gently press down in the middle of the lid. If the lid has no give, it’s sealed. If you can press the lid in and it pops a bit, your jars are not sealed.

How to Can Tomato Soup {Water Bath Canning}

Follow all the steps above for blanching, making, and jarring the tomato soup base.

Prepare your water bath canner by filling it with water. You need to have enough water to cover the jars by 1 inch once the water is boiling.

Set the canner on the stove. Turn the burner to high.

Using canning tongs, carefully place your jars in the canner. Put the lid on. Processing times will vary based on altitude. See the chart below. Pro tip: the water must return to a boil in the canner before you can start the timer.

Once the jars have been processed for the appropriate amount of time, remove the canner from the burner, wearing oven mitts, carefully take off the lid of the canner, and allow it to sit for 5 minutes. Pro tip: I tend to just slide the canner into the middle of my stove, as it weighs a ton.

Carefully remove the jars with canning tongs, and place them on a thick towel in a place where they can be undisturbed for 12 hours.