Canning your own tomato sauce is a great way to preserve tomatoes. Whether you grow your own tomatoes, found a great deal at the grocery store, or picked up tomatoes from a local farmers market, canning tomatoes is much easier than you might believe.
Discloser Note:
This post may contain affiliate links, which means I make a small commission at no extra cost to you. See my full disclosure here.
Table Of Contents
Tools You Need For Canning Tomatoes
- Large Stock Pot For Water Bath Canning
- Silicon Canning Trivet
- Canning Set With Funnel, Jar Lifter, Air Bubbles Popper/Measurer
- Pint Size Mason Jars
- Electric Strainer or Food Mill
- Lemon Juice Or Ball Citric Acid
- Paste Tomatoes
- Optional Seasonings (salt, pepper, oregano, basil)
- Ball Complete Book Of Home Preserving
Note: Please read the instructions in their entirety before beginning.
Step-By-Step Tutorial For Home-Canned Tomatoes
How To Prepare Your Tomatoes For Canning
To begin you will need to prepare your fresh tomatoes for the canning process.
You want to have selected firm, ripe tomatoes with no obvious signs of disease or spoilage.
Next, wash tomatoes under cool running water to remove dirt. You can gently rub them to ensure they are clean. For a more thorough cleaning, you can soak them in a solution of water and a small amount of vinegar for a few minutes, then rinse.
I suggest that you either quarter tomatoes or cut them in half depending on the size of your tomatoes.
How To Prepare Your Canning Jars
Glass canning jars are the only containers that are recommended to be used for safe home food preservation. Check to be sure that the top of your jars are smooth, free from chips, and flat to accommodate the sealing process.
Prepare your jars by washing them, along with the lids and bands, in hot, soapy water. You can do this by hand or in a dishwasher.
The jars will need to be heated before filling them with your tomato sauce. You can keep them warm using a setting on your dishwasher or by processing them in a water bath canner at a simmer. Heat processing destroys any microorganisms in both food, containers, and closures.
Beginning The Canning Recipe
Following the Basic Tomato Sauce recipe from Ball Complete Book Of Home Preserving (page 360) you will place your cut tomatoes into a large pot.
Bring the tomatoes to a boil over medium-high heat while stirring frequently to prevent the tomatoes at the bottom of your large pot from burning. You can use a potato masher, or large spatula to crush the tomatoes in order to release the tomato juice.
Continue to add tomatoes to your large pot while you work being sure to stir constantly to prevent burning. It is helpful to keep the mixture boiling while you are adding and continuing to crush the tomatoes.
Once all of your fresh tomatoes have been added to the large pot allow the tomatoes to boil for about 10 minutes until all of the tomatoes are soft and juicy.
Remove The Skins And Seeds
Removing the skins and seeds from tomatoes prior to canning is important for several reasons. Both the skins and seeds from the tomatoes will have an impact on the texture, flavor, and consistency of your tomato sauce. However, the most important consideration is safety.
A canning recipe is developed around very specific ph levels in order to keep the product shelf stable and safe for consumption. The skins of from your tomatoes, if left in the sauce, would alter the acidity levels and therefore compromise the safety of your finished product.
You can remove the skins and seeds by working in batches with an electric strainer or food mill. If you do not have an electric strainer or food mill, blanch, peel, core, seed, and chop tomatoes. Place in a colander and let stand for about 15 to 20 minutes. Discard any liquid and then use a food processor or blender to puree the tomatoes.
Completing Your Tomato Sauce
After removing the skins and seeds return your tomato mixture to your large pot or saucepan and bring to a boil while stirring frequently.
At this point you may add your seasonings if you choose to do so.
I recommend adding:
- 2 1/2 cups finely chopped onions
- 3 cloves garlic, finely chopped
- 1 1/2 tsp dried oregano
- 1 tsp salt
- 1 tsp freshly ground black pepper
- 1 tsp granulated sugar
- 1/2 tsp hot pepper flakes
This may not seem like much seasoning for such a large amount of tomato sauce. My reasoning for this is because I personally like to leave my jars of tomato sauce with room for versatility to be used in a variety of dishes. For example, I season a pasta sauce differently than I season a pizza sauce. So by keeping the amount of seasoning in my canned tomato sauce lighter I am better able to change up each jar and season it more thoroughly at the time that I am ready to use it.
Continue to allow your sauce to boil until the volume is reduced. You will need to boil the sauce longer if you prefer a thicker sauce. The thickness of your sauce is determined only by your personal preference and how you like to use your tomato sauce.
Before you move on to the canning process you will want to ensure that both your canning jars or mason jars as well as your sauce are hot. Do not try to can with tepid sauce or cold jars.
Water Bath Canning Your Tomato Sauce
We will be canning our tomato sauce using a water bath method. Tomatoes can be canned using a pressure canner if your prefer and instructions for that canning method can be found on page 376 of Ball Complete Book Of Home Preserving.
How To Fill Your Canning Jars
Work to fill your canning jars one jar at a time rather than trying to fill multiple jars at the same time in an assembly line method.
Place your hot jar on a heat protected surface such as a kitchen towel. If you place a hot jar onto your cold countertop the jar is likely to break as the drastic temperature difference causes a thermal shock to the glass.
First, add the lemon juice or citric acid to your hot jar. For a pint jar you will add either 1/4 tsp of Ball Citric Acid or 1 tbsp of bottled lemon juice. The lemon juice must be bottled and not squeezed fresh.
Second, using your canning funnel ladle the hot tomato sauce into the jar leaving 1/2 inch head space for pint jars.
Third, remove any air bubbles by running the air bubble popper/measurer down between the sauce and the inside of the jar. Not removing air bubbles can prevent the jars from sealing properly.
Next, check again to ensure that your headspace is still at 1/2 inch and adjust the headspace as needed by adding or removing sauce from the canning jar.
Finally, using a paper towel that has been damped with white vinegar or warm water, wipe the rim of the jar. This will remove any particles of food that may be on the rim of the jar which would prevent the jar from sealing properly.
Adding Lids And Rings To Your Canning Jars
Place the lid onto your jar followed by the band or ring. Using your fingers, screw bands down until the resistance is fingertip-tight. Do not use excessive force or any kind of tool to tighten the band. Overtight bands will prevent your canning jars from venting and can lead to seal failure.
Processing Your Jar Of Tomatoes
As you fill each of the hot jars place them into your canning pot making sure that the jars on sitting on a silicon canning trivet and not placed directly on the bottom of your canning pot.
When all of your jars are in the pot of water adjust the water level so that you have enough water to cover the jars by at least 1 inch.
Cover the canning pot with a lid and bring water to a full rolling boil over high heat.
Once the water is continuously boiling then set a timer for a processing time of 35 minutes for pint size jars. The rapid boil must continue for the entire duration of the processing time.
The last step to process pints, after your 35 minutes in boiling water, is to turn off the heat and remove the canner lid. Allow the canning pot to cool for 5 minutes before you remove the hot jars and set them on a heat protected surface, such as a kitchen towel.
Leave the jars undisturbed for 24 hours before checking the seal.
Checking The Seals And Storing Your Jar Of Tomatoes
After 24 hours has passed remove the bands from each jar of tomatoes.
Press down on the center of each lid to make sure there is no up and down movement and no popping sound. Properly sealed jars should be concave (curve downward) and will have no movement when pressed.
You can also place your fingertips around the edges of the lid and carefully lift the jar while supporting the jar with your other hand. A properly sealed lid will stay firmly attached to the jar whereas an improperly sealed lid will be loose.
Jars that have not sealed properly must either be immediately reprocessed using a new lid or refrigerated.
All of your sealed jars can be labeled and stored in a cool, dark place such as a pantry or cupboard. Ring or bands should be stored separately from the jars.
Frequently Asked Questions
Paste tomatoes are the best for canning due to their low water content. Roma tomatoes, San Marzano tomatoes, and Amish paste tomatoes are all excellent for canning because they have fewer seeds, less water content, and more flesh, which results in a thicker and richer sauce. However, other varieties like beefsteak or cherry tomatoes can also be canned, though they might require longer cooking times to reduce the water content.
Yes, adding lemon juice or citric acid is essential to ensure the acidity level is safe for canning. Tomatoes have a borderline pH, and adding acid helps prevent the growth of botulism bacteria.
Both methods can be used, but it depends on the recipe and the type of tomatoes. Whole, crushed, or juiced tomatoes with added acid can be processed in a water bath canner. However, if you’re canning low-acid tomatoes or not adding acid, a pressure canner is necessary to ensure safety.
Properly canned tomatoes can last up to 12-18 months when stored in a cool, dark place. After this period, they may still be safe to eat if the seal is intact, but the quality, flavor, and nutritional value might decline.
Signs of spoilage include bulging lids, leaks, off-smells, mold, or spurting liquid when the jar is opened. If any of these signs are present, discard the contents immediately.
Removing air bubbles ensures a better vacuum seal and reduces the risk of spoilage. Use a non-metallic spatula or bubble remover tool to release trapped air before sealing the jars.
You can reuse canning jars as long as they are not chipped or cracked. However, lids should not be reused as the sealing compound may not provide a reliable seal after the first use. Rings can be reused as long as they are not rusty or damaged.
Ensure the rim of the jar is clean and free of food particles before placing the lid. Apply the lid and ring fingertip-tight. After processing, let the jars cool undisturbed for 24 hours.
After processing, allow the jars to cool undisturbed for 12-24 hours. Do not press on the lids or move the jars during this time.
-The lids should be concave (curved downward) if sealed properly.
-Press the center of the lid. If it does not move or pop up and down, the jar is properly sealed. If the lid pops back up, the seal is not secure.
-Once the jars have cooled, remove the screw bands (rings) and try to lift the lid off with your fingertips. A properly sealed lid will remain firmly attached. If the lid comes off easily, the jar did not seal properly.
If a jar did not seal properly, you have a few options:
Reprocess: Reprocess the jars within 24 hours using new lids. Ensure that you follow the correct processing times and methods.
Refrigerate and Use Soon: If you do not wish to reprocess, refrigerate the unsealed jar and use its contents within a few days.
Freeze: Transfer the contents to a freezer-safe container and freeze.
Delicious Soup Recipes
INSTANT POT MINESTRONE SOUP RECIPE
Leave a Reply