Throw on an apron, some opera and a pair of rubber boots ... you're about to learn how to can tomatoes with a tomato press. Plan to set aside 22 mason jars and a day to do this unless you come from a large Italian family with plenty of helping hands.
So, you want to can your own tomatoes do you? You're feeling like an Italian pioneer are you? Good. Glad to hear it. Pressing and canning tomatoes is a bona fide "thing" and not something you can do without a bit of planning and a bit of know how. Luckily for you ... I'm here to show you how to do it.
I've always used the method passed down from my mother who had it passed down to her from someone else. I used that very method right up until the day I realized that method could kill me.
For the first decade of pressing tomatoes I just boiled the tomato juice, ladled it into a hot jar and put the lids on them. No processing at all. That's the way they did it in the olden days and I like to do most things the traditional way. The problem is ... things have changed since the olden days.
Does tomato sauce need to be pressure canned?
No, but they need to be water bath canned. Tomatoes aren't acidic enough to store without a) adding extra acid and b) processing them with a water bath. Newer hybrid tomatoes are even less acidic than heirloom varieties like San Marzano.
I don't know about you but if I'm going to die from self inflicted stupidity I'd rather it be something fun like inhaling too much laughing gas or some sort of Bouncy House mishap. Not from eating botulism infused pasta.
So process your tomato juice.
Table of Contents
Canning Refresher
Water bath canning means submerging the jars so they're covered with a couple of inches of water and boiling them for a certain amount of time. You can do this with a water canning pot or even a regular pot if you have one that's big enough.
Pressure canning means using a specialized piece of equipment - the pressure canner. Jars are put inside with a couple of inches of water in the bottom, the lid is locked and the pressure canner builds up pressure and steam inside. This build up changes the atmospheric pressure in the pot and the boiling point of the things inside it, which in turn kills pathogens.
That is your canning lesson for the day. What worked for gramma's heirloom tomatoes (or any other veg/fruit) may not work for today's Frankentomato. The basic canning methods haven't changed, but food has.
Don't eat bird poop
- Tomatoes need to be washed before you put them through the press. If you don't clean them thoroughly any dirt that's on them will end up in the sauce. Not only dirt but bird poop. You can either lay them on a tarp and spray them with the hose or do what I do - wash them in the bathtub.
- Cut any tomatoes that are too big in half. If they won't fit down the funnel and chute they're too big. It'll make your life easier later on when you're pressing.
How to Press Tomatoes
It may take a few tries to get your press set up the way you like it. The height of the table or bench you have the press on will be a matter of preference.
This old setup of mine looks horrific, but it does what it needs to do. The 2x4 gave me a solid place to clamp to, the upside down plastic pot raises up the stainless steel pot so the juice doesn't splash when it drops into the stainless pot and the garbage bag catches the seeds and skin to stop them from getting everywhere and/or falling into the pot.
Equipment
- Tomato press (manual or electric)
- Large stainless steel pot
- Garbage bag
Instructions
- Wash your tomatoes the day you are going to press them.
- Set up your press by putting it on a table. Clamp it to a table if it's a hand crank model.
- Place the stainless steel pot under the juice chute. Place a food safe plastic bag on the end where the seeds and skin come out to catch them so you can process them again.
4. Drop tomatoes into the top of the funnel, pushing them down with the tamper while you crank.
5. The tomato press automatically filters the tomato pulp and juice from the seeds and skin. Keep cranking.
If you're going to run the seeds and skins through the press again make sure you use a food safe plastic bag, not a green garbage bag.
6. Continue feeding tomatoes into the press until all your tomatoes have been pressed.
7. Now take the seeds and skin you saved in a second pot or plastic bag and put those through the tomato press again. You can press the discards 1-2 times to get as much product out as possible. The final time you run the pulp through it should be almost completely dry.
8. Bring your pot inside, put it on the stove and bring it to a boil. Gently boil for 15 minutes.
Once these steps are done you're ready to process them.
This whole event will be much easier if you have the proper tools.
You can buy an inexpensive kit that includes a funnel, a magnetic stick for picking up hot sealers and tongs for transferring jars into and out of the pot.
This is the exact electric tomato press I've owned for years. It's currently only available in the US.
This is a more affordable electric press that gets good reviews available in Canada & the US.
Check out this tomato press in Canada
Check out this tomato press in the US
How to preserve tomatoes in mason jars.
- Once your tomatoes have come to a boil for 15 minutes, you can start jarring your sauce.
- Add 1 teaspoon brown sugar, ½ teaspoon citric acid and ½ teaspoon salt per quart jar.
- Put a funnel over your jar and ladle in hot tomato sauce to ½" headspace* from the top of the jar.
- Wipe the rim of your mason jar with a wet paper towel or cloth to remove any drips that will interfere with the seal.
- Place the sealer on top and then the ring. Finger tighten only.
- Using tongs place the jar into the pot of hot water.
- Continue until the pot is full and then bring to a boil. Boil for 45 minutes.
*head space is VERY important. Too little headspace and your sauce will be sucked out of the jar and sealer while processing. Too much headspace and you might not get a proper seal.
Do yourself a BIG favour and cover your work surface with a few tea towels. It's gonna get messy.
How many tomatoes do you need for canning?
1 bushel will get you 20-22 quarts of tomato juice.
2 bushels of tomatoes will get you 42-44 quarts.
These tomatoes will last me 2 years and I'll use them to make:
Gramma's Spaghetti & Meatballs
Canning Tomatoes
How to press and can tomatoes for sauce.
Ingredients
- 1 bushel Plum Tomatoes
- ½ cup Brown Sugar / 1 tsp. per quart jar
- ¼ cup Coarse Salt / ½ tsp. per quart jar
- ¼ cup Citric Acid / ½ tsp. per quart jar
Instructions
Notes
Tips for Canning
- Get everything washed, organized, laid out and ready to go the night before.
- If you don't have a canning pot, just use a large pot and place a metal trivet on the bottom. (the water needs to circulate around and under each jar)
- If your tomatoes are muddy and dirty wash them in the bathtub. If a few only have a bit of surface dirt, just wipe them with a dishtowel.
- Some people also add in a basil leaf to infuse basil flavour into the sauce. I do not.
- Play opera while you're spending the day pressing tomatoes. Even if you don't like opera.
I've done this so many times it's second nature so if you're unsure or think I've left something out let me know.
Now get out there, buy a bushel of tomatoes, turn on some opera and give it a shot.
Hi Karen, Thanks for the info! I've been pressing my blanched tomato through a sieve with the back of a spoon. Ugh!
I went to Amazon via your link and bought the Oxo food mill instead of the dedicated tomato press. Many years ago, I used a food mill to make baby foods, which worked well. I'd forgotten about it. The Oxo food mill is affordable at $80 Cdn, and it's stainless steel with an enameled exterior, so it's easy to clean and handsome. I can't wait to get it. I have a bumper crop of San Marzanos and lots of other tomatoes too. Have you ever grown Indigo Rose tomatoes? They're gorgeous little black tomatoes. Tasty too! This is the first year I've grown them but it won't be the last. Thanks again for prompting me to up my canning game. :)
Hi Hettie. Yes, food mills are fantastic! So many uses. And yes I have indeed grown Indigo Rose tomatoes. :) They have excellent flavour too. ~ karen!
I love your setup! I need to do something like that with the 2x4 and clamps because my countertops are too thick for the strainer. What clamps do you use to hold down the 2x4?
I've done this for many years and am so glad you mentioned the often forgotten 'change' that made water bath canning necessary - the change in the hybrid tomatoes being less acidic. I did see that you didn't cover the jars over with water and wondered what you know that I don't (plenty I'm sure). I thought you had to cover the tops to make the proper sealing happen or to insure the heat was reached.
Also, I've read that pressure canning is done to raise the temp of product to above boiling which is only done by pressure canning as boiling just boils the water which evaporates into steam but botulism can only be killed (in low acid food) from a higher than boiling temperature. Ergo - pressure canning. Which has nothing to do with canning tomatoes but I love learning and thought I'd mention that bit.
This is how my Italian grandma made tomato sauce:
She never used a water bath but she boiled the tomatoes for an hour to an hour and a half before putting it through the machine. Then boiling it again before putting sauce in hot jars. She also told me when she was growing up in Italy at the turn of the century (1900) they boiled down the sauce, laid it on grape leaves in the sauce and dried it so they could eat during the winter.
Personally, I prefer the officially sanctioned (NCHFP, USDA) method that Karen outlined. Anyway, who has a time to watch a boiling pot for hours? Drying is a good method, though. Did you know you can also dry the skins of tomatoes and grind it to make tomato powder to add to various dishes to intensify the tomato flavor?
The link to Amazon for the tomato press isn't working. I want to look at the electric version.
Thanks for letting me know Judy. I've updated it and included another link to a more recent and less expensive option that I think looks good. ~ karen!
What is the purpose of heating the tomatoes up before jarring them, when I made them with my parents we never heated the tomatoes up once we crushed we put them right in jars and then heated ups for sealing
I have a vegetable strainer attachment for my Kitchen Aid mixer that does this exactly!
You do have to cut the tomatoes up into maybe max 2" pieces. I bought a separate tray for it that is larger than the one it came with. The juice comes out the bottom and the seeds and skin come pooping out the side. I always put them through again to get all I can out of them. I grow heirloom tomatoes every year so I usually can two or three times over the course of the summer, and while this juicer would probably be less convenient to use than your dedicated tomato press if I were processing a whole bushel, I can easily do 10 lbs of tomatoes in short order. I have been doing this on my kitchen counter, but I think next time I will take it outside to my outdoor table so it will be at a better height for pushing the tomatoes down into the strainer, and I won't be wiping tomato seeds off my kitchen cabinets.
Yeah, I'm sure the mixer attachment works great! Same thing. You also have to cut the tomatoes to fit in the hopper of the electric tabletop model. Unless you want to mash them in, which inevitably ends up with exploding tomato everywhere. ~ karen!
Um, no.
I love you Karen, I truly do, and I do lots of the things you recommend, but not this.
I buy canned tomatoes from a local Italian market. Buy em by the case, and have been happy with them. They taste good, and there’s no mess.
I think the point of this is using up the tomatoes from your garden. I have 40 tomato plants that are loaded and found this to be extremely helpful. It's not about keeping the kitchen clean, it's about being self sufficient and not relying on commercial companies for your food.
Evalyn,
I just recently moved from Scottsdale, Arizona to my home country of Portugal, but in an area I am not at all familiar with. HOWEVER, I already see that my choice of residence, that is in Vale de Santarem, in the region of Ribatejo, where they grow ad infinitum tomatoes, produce some of the best wines - for the country and other parts of the world, and the list goes on. Anyway, just as I was getting ready to move to Portugal I came across one of your stories. Since then I have subscribed and always look forward to your emails/newletters/class-like lesson, but filled with a great sense of humour, and an intense passion for all that is food, especially where my interests are. Thank you for taking such time. Now that I live surrounded by tomato farms, I will have to give this a try. Made my first tomato sauce for my famous bolognese, well, even I found it out of this world. It will be hard to buy canned store tomato sauces now I say.
I so appreciate your stories, your sense of humour, your exquisite skill in story telling and yet directions for recipes. I always write my a bit like you, and some find it tedious...they never make it onto the next email. Others impatiently wait for the next one. I have shared your link many times now and know that they all enjoy your posts as much as I do.
Onto my new very very large veggie garden, never had one before, and ALL bio, sitting beautifully near my bio certified orange grove and many other citruses along with pine trees. So much to learn but I truly am living in a peaceful surrounding appreciating Mother Nature's love and hard work. Might have to invite you over for a few days!
Keep it up! Laughter is one my my best life ingredients.
Obrigada!
De nada Simone! I love Portugal, it's beautiful! And the Galâo!!❤️ ~ karen!
This sounds like so many people get so much joy out of canning. That makes me happy to hear. I grew up canning out on the farm, and have done only a very small amount of it as an adult. My favorite was the apple butter we made from apples we picked ourselves. I just don't think I want that mess, or to work that hard, but that was the most delicious apple butter, ever! Sweet apples, so no sugar, and cinnamon, cloves, and nutmeg, to taste. Delicious!!
This brings back memories of the jars down in the cellar on the back porch. I hated going down there - spiders galore!
I have an old workhorse Champion Juicer. Will it work ok? Someone asked the same question but I don't see a reply:
Do you think you could use a juicer instead of a tomato press? Doesn’t it do the same thing-separate the juice from the pulp?
Thanks so much!
Hi Marie. I don't have a juicer, so I can't respond with any authority. All I can suggest is that you make tomato juice with it and see how it acts. Does it remove all the skin? (if not you may have to boil the tomatoes and remove the skin yourself) And will it remove the seeds? You probably don't want juice full of seeds. Give those things a shot and see how it goes. I hope it works for you! ~ karen
Were my tomatoes supposed to separate? I have a bunch of tomato foam at the top of the jars, and a bunch of tomato water at the bottom. :( I forgot to boil them for 15 minutes before canning- is that why?
That's odd. When tomato juice separates the water would normally go to the top. I assume you gave them a boiling water bath? ~ karen
No, I used the pressure canner with the rocker weight to make sure it was working correctly. I found my answer after I asked you- my tomatoes look like the picture.
https://www.healthycanning.com/tomatoes-separating-jars/
I am still struggling with this. I heated all the tomatoes before processing them. I didn't boil them. More juice did come out, but I wonder how much was water? Because now both batches are extremely runny, even after heating them at the end. I am not sure what I am doing wrong?
Hi Jennifer. It doesn't sound like you're doing anything wrong. What you're making is basically a tomato juice. You then cook it to a proper thickness afterwards when you crack open a jar and are making a sauce. Does that help? ~ karen!
I didn't read every comment, but incase no one else mentioned this, if you have a kitchenaid stand mixer you can get the fruit/veggie strainer with food grinder attachment for around 100 USD. It fits in a shoebox for easy storage.
Because my tomatoes don't seem to ripen at the same time, I pop them into a freezer bag and keep them frozen until I have enough to can. I've never used a press because I don't care about seeds and the skins from the frozen tomatoes just slip off. Is there anything else you can use the tomato press for? Other than my canning equipment I really don't like to have a lot of single use gadgets.
I found that a tomato press works amazingly well for taking the seeds out of saskatoons or grapes. Saskatoons grow wild in our area of the country and are great tasting, but are very mealy for sauce - running them through the press removes the seeds and gives you a great sauce for canning and then using in all kinds of desserts, on pancakes, with yoghurt, etc. The same story is true with grapes - to make a smooth juice you can jar, just run it through the press, add a little sugar and citric acid, waterbath, and enjoy all winter.
One tip is instead of tea towels, splurge on a plastic picnic table cover at the dollar store. When the job is done and the mess has been made you can simply throw it out and no cleaning necessary.
I feel like if you're already doing the Laura Ingalls Wilder thing and making your own tomato sauce, just go whole hog and use tea towels so as to send less waste to the dump.
Valid point.