Rinse your tomatoes. It is best to use a low-moisture tomato like romas.
21 lbs tomatoes
Using a paring knife, remove the stem/core from the tomatoes. Place in a large bowl. I like to core about 75% of them at all once.
Wash and sanitize your jars. You’ll want to keep them warm to avoid having them crack when placed in the canner. You can fill them with hot water, or place them on a tray in the oven at 170F.
Wash your lids with hot soapy water and place them in a clean bowl for now.
Fill a large saucepan with water and bring it to a boil.
Prepare a large bowl with ice water. Set aside.
Add the tomatoes to a pot of boiling water and parboil them until you see the skins start to come off the tomatoes (about 1-2 minutes).
Use a slotted spoon and remove the tomatoes and place in the ice water.
Working with the tomatoes one at a time, remove any skin that hasn’t already slipped off.
Once they are peeled you can slice the tomatoes in half (to remove all the seeds) or leave them whole.
If you are hot packing your tomatoes add them to a pot of boiling water and let them cook for 5 minutes.
Add 3 quarts of water to your pressure canner and put it on a burner set to high. Make sure there is a canning rack in the bottom of the canner.
Add lemon juice or citric acid to your canning jars. Quarts: 2 tbsp lemon juice OR 1/2 tsp citric acid. Salt (optional) 1 tspPints: 1 tbsp lemon juice OR 1/4 tsp citric acid. Salt (optional) 1/2 tsp
14 tbsp bottled lemon juice
Using a canning funnel, ladle hot tomatoes in the jars. Cover tomatoes with clean boiling water.
Leave 1/2 inch headspace. Headspace is the distance between the top of the food and the top of the jar.
Using a long utensil (I prefer a plastic chopstick), remove all the air bubbles from the jar.
Clean the rim of the jar very well with a hot damp rag.
Place a clean new lid on the jar. Add a ring, and tighten to fingertip tight.
Using canning tongs, gently place the jars in the canner. Lock the lid. Soon, steam will start coming through the vent pipe.
Allow the steam to pass through for about 10 minutes. Then put the pressure regulator on top. (see photos in post above to see this in action)
Pretty soon, the air vent will pop up. That is a sign that you’re starting to build pressure inside the canner. Whole tomatoes need to be pressure canned at 11 pounds of pressure for 10 minutes for both pints and quarts. (see time chart in post for adjusted times for elevation and water bath canning).
When the dial gauge reaches 11 pounds of pressure, reduce the burner temp to medium, and start your timer. The pressure must stay at 11 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 (Pro tip: I always use oven mitts when I take the lid off because the steam is crazy hot).
Let the jars sit for 5 minutes in the canner and then lift them out with canning tongs. Place 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.
Water Bath Canning Instructions
Follow steps 1-18 above in the Pressure Canning Instructions.
Prepare your water bath canner by filling it with water. You just need to have enough water to cover the jars by 2 inches once the water is boiling.
Set the canner fitted with the lid on the stove. Turn the burner to high. Once it reaches a boil, reduce it to simmer. You want to keep the water hot so that everything is ready when the tomatoes are.
Return the water in the canner to a rolling boil.
Using canning tongs, carefully lower the jars into the boiling water and place the lid on and set your timer.
Pints should process for 40 minutes and quarts for 45 minutes. Pro tip: the water must return to a full boil in the canner before you can start the timer.
Once the tomatoes have processed for the appropriate amount of time, remove the canner from the burner, carefully take off the lid, and allow it to sit for 5-10 minutes. Pro tip: I tend to just slide it into the middle of my stove, as it weighs a ton.
Carefully remove the jars using canning tongs, and place them on a thick towel in a place where they can be undisturbed for 12 hours. The lids should start to pop/ping within 20-30 minutes of being removed from the water.
Notes
Recipe cook times based instructions from the National Center for Home Food Preservation.22 lbs tomatoes per 7 quarts, or 14 lbs tomatoes per 9 pints. About 3 lbs tomatoes per quart.Store in a cool dark place for 9-12 months.