How to Can Crushed Tomatoes

My home has been filled with guests and tomatoes. Right now the dining table is fully extended to accommodate not our guests but 160lbs of Roma tomatoes while the other 40lbs are still in a couple boxes waiting to be laid out. The last of the 180lbs of round tomatoes are being proceed today as crushed tomatoes. A good portion of the round tomatoes (canned) went north with my sister and her husband a few days ago. So far I have put away 45 quarts of crushed tomatoes and 50 pints of basic spicy red salsa. Last year I preserved 72 quarts of stewed tomatoes, 44 quarts of tomato sauce, 41 pints of salsa and 8 pints of ketchup and from all that I only have a couple jars of tomato sauce and ketchup left. I won’t can as many stewed tomatoes this year but there is still plenty of work to be done.

How many tomatoes? 

To determine how many tomatoes you need, first estimate how many quarts (1 L jars) will be consumed each week in your home. If you don’t think you’ll eat a whole quart in a week then envision your monthly consumption. We go through one quart a week of crushed tomatoes, on average. There are 52 weeks in a year so that means we need about 52 quarts of tomatoes plus some extras for doubling recipes.

A quart jar fits an average of 2.75 lbs of tomatoes. If I want 52 quarts of tomatoes then I need about 145lbs of tomatoes.

Use the same steps that I shared on my How to Can Peaches post to calculate pound of tomatoes needed.

Equipment + Ingredients 

Quart sized jars (Tip: use regular, not wide mouth)
Lids + Rings
Jar lifter
Water bath canner
A large bowl (one or more)
Large pots (two or more)
Water bath canning pot + lifter OR Weighted-gauge pressure canner
Ladle, slotted spoon + wooden spoon
Funnel (that fits a regular mouth jar)
Old dish rags and dish clothes
Large propane burner + propane tank (optional but worth having)
Bottled lemon juice
Salt (optional)

Setting Up

Gather all the equipment listed above and set up your work space. It’s important to have an efficient workspace flow so think about the steps that need to happen and arrange the equipment accordingly. Look through the steps below and envision your work space.

Canning Crushed Tomatoes

The first step to canning stewed tomatoes is removing the tomato skins. Fill a large pot with enough to cover half a dozen tomatoes, and bring the water to a boil. Tip: Less water is better because it will take less time to boil.

Before adding the tomatoes to the boiling water take a serrated knife and make a cut through the skin starting from the top of the steam and circling to the other side. This allows the tomato skin to slip off very easily and works much better than making an “X” at the bottom of the tomato. I started skinning my tomatoes this way after reading The Best Way to Skin Tomatoes from Well Preserved.

Submerge the tomatoes in boiling water and boil for 30 to 60 seconds. Plunge the tomatoes into a sink or bowl filled with cool water to stop the tomatoes from cooking.

Remove the skin from the tomatoes and cut out the stem. Quarter the tomatoes into a large pot or several large pots depending on how many tomatoes you have.

When the pot is about a quarter full of tomatoes use your hands to crush them. This will force juice out of the tomatoes which will prevent the tomatoes from scorching when they are heated up later.

Once you’ve filled up the pot set it on the stove. Go ahead and use your hands to crush the tomatoes a little more if you like. Bring the pot to a simmer. As the tomatoes heat up more liquid will be released. Bring the tomatoes to a boil and simmer gently for 5 minutes.

Clean and rinse quart jars and prepare lids. In each quart add 2 Tbsp. of bottle lemon juice and 1 tsp. of pickling salt. The salt is optional but the lemon juice is not optional. Lemon juice ensures that the tomatoes are acidic enough to can safely (for more information read the NCHFP acidification instructions). Fill each jar with hot crushed tomatoes leaving 1/2 inch head space. Place lids according to the manufacturers instructions and tighten the metal rings to finger tip tight.

Process quart jars of crushed tomatoes in a water bath canner for 45 minutes (50 minutes if above 1000 ft elevation) OR for 15 minutes at 10 lbs of pressure (15 minutes at 15 pounds of pressure if above 1000 ft elevation) in a weighted-gauge pressure canner. If using a water bath canner please ensure that the water come to a rolling boil before timing. These processing times are the same as those recommended from the National Center for Food Preservation for crushed tomatoes.