My tomato preservation approach is one that is forever evolving. I make a point of trying at least one new-to-me tomato recipe to each season, always hoping that I’ll discover something particularly delicious and worthy of my time, resources, and shelf space.
This year, there were two experimental recipes. The first was this barbecue sauce (which is quite delicious, but probably won’t be something I make every single year). The second is the tomato soup concentrate that I’m sharing today. I’m already hoping that when I get home from the trip I’m currently on (I’ve been away for a week, which accounts for the blog silence), I’ll be able to get enough tomatoes to make another batch.
Recipes for tomato soup concentrates that are safe for the boiling water bath canner aren’t always easy to find. I did a lot of reading and worked out more math problems than is typically required for a basic canning recipe in order to bring this to you today. I built my recipe upon the framework laid out in the National Center for Home Food Preservation’s water bath safe Tomato and Vegetable Juice recipe.
The thing in that recipe that made everyone here possible is the fact that it specifies that, “Not more than 3 cups of other vegetables may be added for each 22 pounds of tomatoes.” Taking my cue from there, I used 15 pounds of tomatoes, and a scant two cups of diced onions. I felt comfortable doing that, because I was keeping to their approach while reducing the batch size by one-third.
From there, it was a matter of chopping the tomatoes and cooking them down with the onion. Once they were soft, I pushed them through a food mill fitted with its finest screen. At that point, I had approximately 24 cups of flavorful tomato juice.
I added Italian seasoning and granulated garlic, and cooked it down until I had a thick, tasty 16 cups. Once I was finished cooking, I added salt to taste (it’s always best to wait until you’ve finished cooking something down before salting it. Otherwise, you can end up with something inedible).
Then I portioned 1/2 teaspoon of citric acid into five square sided 26 ounce jars from Fillmore Container and filled them up with my soup concentrate. I added five minutes to the processing time required by the NCHFP for the tomato and vegetable juice, to compensate for the increased thickness.
I love canning tomato products in these square sided jars because they give it a more professional look, and I find that the squared off sides make them easier to grab when I’m moving quickly. The 26 ounce size is also great from a portioning perspective. Reheated with a bit of milk, there’s just the right amount for two people to enjoy bigs bowls with a side of cheesy toast or garlic bread.
Disclosure: Fillmore Container is a Food in Jars sponsor. Their sponsorship helps keep the site afloat. They provided the jars you see here at no cost to me. All opinions expressed are entirely mine.
- 15 pounds of tomatoes
- 2 cups diced onion
- 2 tablespoons granulated garlic
- 1 tablespoon dried Italian seasoning
- 1 tablespoon salt, plus more to taste
- 2 1/2 teaspoons citric acid
- Wash the tomatoes and cut them into quarters. Heap the chopped tomatoes into a large pot and add the diced onion.
- Add about a cup of water to the bottom of the pot to prevent scorching. Place the pot on the stove and bring it to a boil.
- Cook, stirring occasionally for about an hour, until the tomatoes have lost their structural integrity and the pot contains nothing but super saucy tomatoes.
- Remove the pot from the stove. Fit a food mill with its finest screen and position it over a large heatproof bowl.
- Working in batches, start pushing the cooked tomatoes and onions through the food mill. You will probably need to stop three or four times to empty out the bowl into a clean pot.
- Once all the tomatoes are milled, add the granulated garlic and Italian seasoning. Set the pot on the stove and bring to a low boil.
- Cook for one to three hours, until the soup concentrate has reduced by at 1/3 and hopefully a bit more.
- When you're pleased with the consistency, stir in the salt. Start with a tablespoon. Taste and add more as needed.
- Divide the citric acid between five jars 26 ounce jars (the Ball brand 24 ounce Pint & Half jars are also a great choice for this one).
- Funnel the finished soup concentrate into the jars, leaving 1/2 inch headspace.
- Wipe the rims, apply the lids and rings, and process in a boiling water bath canner for 45 minutes (if you live above 1,000 feet in elevation, please adjust your processing times accordingly).
- When the time is up, remove the jars and set them on a folded kitchen towel to cool. When the jars have cooled enough that you can comfortable handle them, check the seals. Sealed jars can be stored at room temperature for up to a year. Any unsealed jars should be refrigerated and used promptly.