An Easy Guide to Canning Tomato Sauce
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Canning tomato sauce is such an easy thing to do. Don’t let a good home-grown tomato go to waste. Learn how to can tomato sauce with these detailed, step-by-step instructions. Using Roma tomatoes or other meatier tomatoes like San Marzano will give a thicker sauce. Juicier tomatoes will have to be cooked down more to thicken. Either will work.
Do you want to can tomato sauce with meat? Check out this recipe for spaghetti sauce instead.
Canning Tomato Sauce: Extended, Step-By-Step Directions
Wash tomatoes and remove stems and bruised portions. You’ll need to remove skins.
Removing seeds is optional. When I’m canning tomato sauce, seeds don’t bother me for things like spaghetti sauce or stews and chili. But I would not want seeds in something with a smoother consistency like ketchup or tomato soup. Depending on what your use is for the sauce, you may leave the seeds if you like.
I’ve described three ways to prepare your tomatoes for canning. The method you choose will depend on how you want to preserve it.
- Option one – Use a blancher to remove skins but not seeds.
- Option two – Use a food mill, which will remove both seeds and skins.
- Option three – Use a blender, which does not remove either skins or seeds. (actually not recommended)
I’ll explain the options for canning tomato sauce. Then you can continue at the bottom for ideas of how to use your tomato sauce. Or if you want to can it up just like it is without seasoning, I give full canning instructions below as well.
Blanching to Remove the Skins
This option will remove the skins but not the seeds.
This is easiest done in a blancher. If you don’t have one, you can just use a slotted spoon and a big pot of boiling water.
Blanch 4 to 6 (or more if small) tomatoes at a time. This will always depend on the size of the tomato. In the example pictures, I am doing Roma tomatoes. I like them for canning because they are meatier than other tomatoes. They are smaller too, so I can fit more in the blancher.
- Wash tomatoes and dip in boiling water for 30-60 seconds or until skins split. You will often see the skins separating.
- When you remove the tomatoes, drop them immediately into sink or bowl of cold water to stop the cooking.
- Slip off skins and quarter tomatoes. The skins should just slide off in your hands. (Occasionally, I’ll use a knife on some stubborn spots.)
Canning Tomato Sauce Tip
I like to have two pots set up in my double sink. The one on the left is for the cold water to cool the tomatoes as they come out of the blancher. The one on the right is to slide the skins off into. The pots are lower than if you set them on a counter, which is easier on the arms, while the sink makes for easy clean up.
As you skin the tomatoes, slice them into a pot where they will be simmered.
Skinning & Peeling Tomatoes with a Food Mill
Another way of preparing your tomatoes for canning tomato sauce is to use a food mill. This is my preferred method. The food mill removes both the skins and the seeds.
First, wash your tomatoes in cold water, and then slice in half. Simmer the tomatoes to make them softer for the food mill.
It is easier to do this if you have some juice in your pan to start, so try this: Place a single layer of tomatoes in a pot. As it heats, use a potato masher to crush tomatoes to draw out the juices. When you have a bit of juice in your pot, continue slicing tomatoes in half and adding to the pot.
When all tomatoes are sliced, simmer for 15 to 20 minutes or until tomatoes are juicy and heated through.
Note: There is a reason for heating the tomatoes up as you slice them. Read more about tomato separation, other tomato canning issues and how to avoid them.
I used two large pots to simmer 30 pounds of tomatoes. With the tomatoes split into 2 groups, it is less likely to scorch.
Put tomatoes through the food mill. This removes all skin and seeds.
Use a Blender to Liquefy the Tomatoes for Sauce
This canning tomato sauce option does not remove the skins or the seeds.
Keep in mind that all tested recipes do state to peel the tomato before canning.
In my opinion –and I’ll repeat that it is my opinion— this is a quality issue. The peels in the jars are unappealing. But some insist it is a safety issue since the peels may have a higher bacteria count.
I have an older Ball book that has the option to use a food processor to make your sauce. That method would not remove the peels. This book is dated 2009. The recommendation is that you use a current canning book no more than 10 years old. I guess my old friend is now out of date!
So… you get to decide.
Current recommendations for canning tomato sauce are now to remove those peels completely.
This is an area where you need to make your own decision. I’ll give you the information I have, and you get to decide! :). I admit, I have just blended my tomatoes. I only did it once because I did NOT like those peels.
However now I know better so I do better. I peel the tomatoes.
It honestly does make your sauce or juice or whatever you are making better. The peels are terrible little rolled up things floating around the juice. The best option is to remove those skins.
Canning Tomato Sauce Recipe Instructions
Now you have sauce and are ready for canning. This sauce you just created can be used in recipes like stewed tomatoes or spaghetti sauce if you want. Canning tomato sauce unseasoned is a great idea. It is very easy to use for many recipes when you are ready to cook supper.
Try this time-saving canning tomato sauce tip. Another reason I love the food mill method.
First, bring the tomatoes to a boil. Use medium heat, stirring often to prevent burning. If you had especially meaty tomatoes and your sauce is thick, you may need to just stand there and stir.
It can be canned just as soon as it is hot and bubbly. IF you would like to have a thicker sauce, you can cook it down. Simmer, uncovered, to thicken. Cook until it reaches your desired consistency. Stir frequently to avoid burning! The amount of canned tomato sauce may be reduced by nearly one-half.
An easy way to do this is to place sauce in a slow cooker and leave the lid off. Let it cook until thickened.
Gather your canning supplies for canning tomato sauce:
- pressure canner
- canning jars
- canning lids and rings
- jar lifter and canning funnel
- blancher
- bowls
- large spoons
- sharp knife
- towels, dish cloths and pot holders
- food mill or strainer (optional)
Ingredients:
- 30 pounds tomatoes
- Bottled lemon juice
- Salt (if desired)
Do You Have to Add Lemon Juice When Canning Tomatoes?
For more information on why acidifying your tomatoes is important, please read: Canning Tomatoes Safely This article explains why you really do need lemon juice.
Processing tomato sauce
To process the sauce just as it is: Fill hot jars. Add 1 Tbsp. lemon juice to pint jars and 2 Tbsp. lemon juice to quart jars. Leave 1-inch headspace.
Follow pressure canning instructions. This is my preferred method and is what I’ve included below.
Be sure and adjust your processing to your altitude.
Processing Time
Be sure you are using the correct time with the correct method. Double-check…water bath? Or pressure canning? And be sure to use the instructions for your altitude.
For more information on why this is important, see this altitude adjustments page.
Pressure Canning Tomato Sauce
Process pints and quarts for 15 minutes, adjusting for altitude using the chart below.
Water Bath Canning Tomato Sauce
Process pints for 35 minutes, adjusting for altitude using the chart below.
Process quarts for 40 minutes, adjusting for altitude using the chart below.
Comments, Tips, & FAQs
Home-canned tomato sauce keeps at least 12 months in optimal storage conditions, but again, that’s just a quality issue. Canned food doesn’t automatically spoil when 12 months hit! However, quality begins to degrade at that point, so make a point to use it up sooner, that’s all.
If you open a jar of tomato sauce and aren’t going to use it all in a timely fashion, you can certainly freeze leftovers for later. But usually, I’ll use most of the jar at once! (That’s why it’s important to decide beforehand whether you’ll use pint or quart jars, depending on how much you’ll use at once.)
If you are wondering about freezing the tomato sauce instead of canning. Then again yes you can simply pack in freezer-safe containers and pop them in the freezer. I’ve got more on freezing tomatoes here
Romas are most commonly used for the sauce. You can use other tomatoes too, but know they’ll be juicer and thus will require more cooking to make a thick sauce.
Yes, absolutely. You can refrigerate the sauce as it is and then can it tomorrow. You will need to reheat the sauce, then jar it and process it as a hot pack as usual. Do not put the jars in the refrigerator. Store the sauce in a pot or container and fill hot jars with hot sauce tomorrow.
When I jarred my tomatoes and took them out of the water bath, I see they have a lot of air bubbles. Is that ok?
Sharon’s Answer: When you say ‘a lot’ that can be pretty subjective. There may be some air trapped between the tomatoes but it should not be a lot. As long as the bubbles are not actively moving, like the tomatoes are fermenting, the air bubbles won’t hurt. Be sure you canned them with the correct processing methods. Read more about canning tomatoes here.
By: Deb
I have been canning sauce in quart jars for a very long time. Now with an empty nest, I only need pints. My problem is I have tons of quart jars and only a few pints. My question is, can I process half-filled quart jars of sauce?
Sharon’s Answer: No, you need the headspace to be correct in the jars, so half-filled jars would not work. You are better off going with pint size jars.
Hello, I read your answer regarding Botulism and how we should use a canner to process tomato sauce. Last year I followed my husband and his grandfather’s lead and they neither added lemon nor processed with a canner. I hadn’t done my research last year – now I add 2 tablespoons of lemon juice to a litre of sauce therefore the pH enters the safe zone preventing the spore – found in soil – to produce the bacteria.
This said, how would contaminates from air or utensils change this? From my understanding, the spores may be present and boiling does not kill them – but changing the pH prevents this from producing bacteria. Did you mean that the contamination with air and utensils provide problems other than botulism?
Also, would heating the sauce to 185F for 5min before consumption kill botulism if ever the spores were to produce bacteria?
Thank you so much, Signed-my husband is Italian and thinks it’s overkill since his family has been doing this for generations-and I’m a concerned doctor.
Sharon’s Answer:
You really need to use tested methods for canning. Adding lemon juice if you are using a water bath is what is recommended. Don’t rely on the boiling after the fact.
As far as the debate with your husband…no advice here. 🙂 Just wishes for good luck.
Sure, The directions are included above in the recipe card.
Related Pages
Tips for Home Canning Tomatoes
It’s tomato season, and you’ve got a counter full of tomatoes beckoning you. Before you start canning, here are 3 things you should know about home canning tomatoes.
Freezing Tomatoes
Freezing tomatoes can be as straightforward or as complicated as you want it to be. With or without skin, cut or whole, with a ‘how to’ video included.
Source: The National Center for Home Food Preservation
Page Last Updated: 6/24/2021
I made a large pot of sauce, refrigerated it overnight and then canned it the next day without first reheating the sauce. Is that ok? I now see that most recipes recommend reheating the sauce before you process it in the water bath. The process went well and the jars sealed, but I’m worried. Thoughts?
You do need to start with hot jars. So you should have reheated it first. I would not consider this safely preserved.
I water bathed 14 pints of tomatoe sauce, using a tbsp of lemon juice in each jar, but at the end of the process when i removed the jars, I noticed about an inch of liquid (tomatoe water) in the bottom of almost every jar, and the solid portion of the sauce was floating above it. Is this ok?
Hi Gail, That separation is just a cosmetic thing. It is still perfectly safe as long as you used a safe recipe.
hi I used a canning packet for tomato sauce and it had citric acid in it so we did not add lemon juice to our jars will they the jars be ok?
Yes as long as you follow the directions on the packet you are fine. :).
In the latest Ball Blue Book page 33 for the recipe “Basil-Garlic Tomato Sauce” they call for 40 minutes of water bath for quarts. What if one wanted to use a pressure canner instead, what would be the processing time? Why doesn’t Ball list the time for both water bath and pressure canner? Everyone may not have both processes available.
Purchase a pressure canning book and it will tell how to can tomato sauce and the processing time!
I use 25 lbs tomatoes, put in hot water, peeled and quartered and used a food mill. All I got was juice and about a pint of meat. What did I do wrong.
It is likely that you just had extra juicy tomatoes. Using a paste tomato variety gives better results for a thicker consistency.
Sharon, thanks for your information! I added carrots to my tomatoes and forgot to add lemon juice before canning. Are the carrots enough to lower ph and prevent botulism or do I have to start over? Or can I just use the jars within a short time? Thanks!
Hi, Linda,
Unfortunately, carrots are a low-acid food (like other plain veggies), and thus they are at a higher risk of botulism. With tomatoes in particular, it’s important to use a tested recipe when combining tomatoes and vegetables, such as in this stewed tomatoes recipe: https://www.simplycanning.com/canning-stewed-tomatoes/ The ratios are very precise. If it’s just been 24 hours, you may store the jars in your fridge for immediate use, but they shouldn’t be stored on the shelf. I hope this helps!
-Rachel (Sharon’s assistant)