- ½ bushel (about 25 pounds) ripe plum tomatoes
- 1 pound onions, finely diced
- 4 cloves garlic, peeled and minced
- FOR EACH PINT JAR
- ½ teaspoon salt
- ¼ teaspoon citric acid
- FOR EACH QUART JAR
- 1 teaspoon salt
- ½ teaspoon citric acid
A note on equipment to make tomato sauce in quantity: I use the fruit strainer attachment with my KitchenAid stand mixer, but you could use a hand-crank version, as I did for many years. If you use a hand-crank model, recruit a strong young helper, and bribe him/her with jars of finished sauce.
Look for paste tomatoes; it’s important that you find tomatoes as meaty as possible. Wash the tomatoes to get dirt and debris off the outside, and checking each one for blemishes or moldy spots. Soft or split tomatoes are fine to use, but cut out any black or spoiled spots. Cut the tomatoes lengthwise in quarters, as they’ll fit through the strainer better.
squeeze and strain tomatoes
Follow the directions for your specific strainer. You’ll want the squeezings (the remains) to be as dry as possible. I put them back through the strainer once or even twice, to extract the most pulp that I possibly can. At my house the seeds and skins go into the compost pile, though Joel MacCharles at wellpreserved.ca likes to dehydrate them and use the resulting tomato powder as a seasoning.
Put all the tomato pulp with the onions and garlic in a wide pot, and begin cooking it. Bring it to a full boil, and then reduce the heat to a simmer, stirring occasionally, until the sauce is reduced by at least half. This can take hours, depending on the size of your pot. A wide pan is much much better for this – greater surface area will reduce the sauce more quickly. You’ll get better flavor from a slow simmer than from a violent boil.
In the summer of 2014, we cooked the tomatoes outside, only using the stove in the kitchen to seal the jars. We used a Browning stove with 2 30,000 BTU burners, and were able to keep two big 20-quart pots bubbling at once. It kept the mess (wash, cut, squish, AND cook) in one place, where the crew could switch jobs, chat, share jokes and stories, and laugh at the confused squirrels who hoped for handouts.
prepare jars and lids
As always, have your jars clean and hot. If you’re going to put hot sauce in jars, then the jars in hot water, you need hot jars! Thermal shock can crack glass, and your work is wasted. If you are using the new “made in USA” lids, do not heat them. Add the appropriate amount of salt and citric acid to each jar.
fill and seal jars
Ladle the sauce into the prepared jars, leaving ½ inch headspace. Release any air bubbles trapped by sauce. Wipe rims clean, cap and screw on jar bands. Process in a boiling water bath: 35 minutes for PINT jars, and 45 minutes for QUART jars.
When the time is up, turn off the heat, remove the canner lid, and let the jars rest, still in the water, for 5 minutes. Remove jars, place on a towel-lined counter, and set them aside for 24 hours. After that time, remove the bands, check the seals, label, and store the jars in a cool dark place for up to a year.
about safe canning
It’s critically important to balance the quantity of low-acid vegetables with added acid, in this case powdered citric acid, which is easily available where you can buy canning jars and other equipment. The tomato sauce must be acidic enough to be safely processed in a boiling-water canning method. Do not increase the onions and garlic; do not add other vegetables; do not add oil. Feel free to seek out reputable sites for more information and recipes – I have a list you might like to start with on my Canning Information page.