A great way to preserve extra tomatoes for the winter months is to can them – and it’s easier that you think! Here’s how to can your own tomato sauce – step-by-step…
One of the easiest things to can – in my opinion – is tomato sauce. Tomatoes are plentiful in our garden every summer (sometimes a little too plentiful – right now we have already filled all of our canning jars plus numerous freezer bags, and tomatoes are still piled on the counter and rotting in the garden…), and their natural acidity means you don’t have to do too much to them to make them safe for water bath canning, which can be done in your own kitchen without a lot of specialized equipment.
All you need is a large kettle (we have a canning kettle, but you can also use a large stock pot – you’ll just have to do smaller batches), canning jars, some canning lids and rings (we like the reusable kind), and a few canning accessories (we got a cheap kit that included a canning funnel, jar lifter, and magnetic lid lifter for around $10).
Not only are they easy and affordable to make at home, but you can use canned tomatoes in so many different ways – pasta sauce, pizza sauce, soups, stews, chili, and so much more. Despite all these tasty ways that we we enjoy eating tomatoes, I am proud to say that we haven’t purchased canned tomatoes or tomato sauce for more than 3 years now, and hopefully, we will never have to again!
Below is a basic recipe for canned tomato sauce from Melissa Norris – we do basically the same process, though we usually just do them plain (without the basil), and “doctor” them up when we eat them.
We also peel ours, as my husband hates tomato peels, but that is totally optional. If you do want to add that step, you would blanch the washed and cored tomatoes in boiling water for about 1 minute, then drop into cold water and slip the skins off before chopping.
We can all sorts of tomatoes, but the bulk of them are paste tomatoes – either San Marzano or Nova – both wonderful varieties for canning.
What you’ll need (in addition to the equipment listed above):
Tomatoes (about 20 pounds makes 7 pints of sauce)
Bottled lemon juice
Sterilize your jars in boiling water for 15 minutes, or using the sterilize cycle of your dishwasher. We just put ours in the canner while the water is heating to boiling and we are working on the tomatoes, then remove to a towel to drain before filling.
Wash your tomatoes and core them + cut out any spots
Peel if desired (using the tips above). Then roughly chop about 6 tomatoes, and put in a large pot.
Cover the bottom of the stock pot in one layer of chopped tomatoes. Take a potato masher and squish them to get some juices running. Turn the pot on medium high. Wait until it begins to boil and then add 6 more chopped tomatoes. Stir frequently to prevent scorching, but also make sure the tomatoes continue to boil.
Continue adding chopped tomatoes one layer at a time until you’ve added all your tomatoes or you’re in danger of overflowing your pot. You can also use two pots if you’re doing a large batch – but make sure your canner is big enough to fit all your jars! After you’ve added all of your tomatoes and mashed them, continue to boil for about 10 minutes. You want all the tomatoes cooked and mooshy, with the glorious juice released.
Step 6 (Optional):
If you prefer a smooth sauce or juice, you can now put your cooked tomatoes through a food mill or puree them to your desired consistency, then cook them down over low heat until the sauce is thickened to your liking. Since we peel ours first anyway, we just jar them as is – we’re lazy like that!
To each scalded jar, add:
1 Tablespoon bottled lemon juice per pint (2 Tablespoons per quart jar)
1/4 teaspoon salt per pint (1/2 teaspoon per quart) (OPTIONAL)
1/2 teaspoon dried basil per pint (1 teaspoon per quart) (OPTIONAL)
These should be added to each jar, not the pot of tomato sauce.
NOTE: You must add the bottled lemon juice for safe shelf stability!
Fill jars with tomato sauce up to a 1/2 inch headspace for water bath canning and 1 inch headspace for pressure canning. Run a spatula around the jar circumference to remove air bubbles. Add more tomato sauce if needed to keep 1/2 inch or 1 inch headspace depending upon your method of canning.
With a damp clean cloth, wipe the rim of the jar clean. Place on lids and screw down the bands to fingertip-tight.
Water bath instructions: Place jars in waterbath canner, make sure rack is in place. Make sure at least 1 inch of water is covering the tops of the jars. Bring to a roiling boil and then process pint size jars for 35 minutes or quart jars for 40 minutes. Turn off heat and remove the lid from the canner. Allow jars to rest inside the waterbath for 5 minutes. If you remove them immediately you run the risk of cracking the jars or the siphoning of liquid, which can inhibit a proper seal. (For pressure canner instructions, see this article.)
(Oops! I just realized that must be why I’ve sometimes had problems with stuff leaking out and lids not sealing!)
Remove jars and place in a draft-free area on a drying mat or a towel folded in thirds. Never place hot jars on a cold counter top! Don’t touch jars for at least 12 hours, 24 hours if you have the counter space.
Remove rings, check seals, and move to the pantry for storage. (If you notice any stickiness on the outside of your jars, clean them well with a damp towel before storing to prevent any mold on the outside.) Check seals every month or so by gently pulling on each lid or pressing the center to make sure they are still suctioned down, and discard anything that loses its seal. Stored in a cool, dry place, canned tomatoes will easily keep for over a year.