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.
First of all - my music selection would be the soundtracks from the Sopranos...enough said.
Secondly, the choices of tomato/food strainers must be awesome, because both are pretty much sold out! But I will keep checking, as I love this post and embrace a gizmo that would produce sauce like this. Hubby loves pasta/sauce so would be all over this purchase!
HI Karen, This is a fascinating post. I had no idea that tomatoes have actually changed. My mom does not water bath them, and we've not had any trouble, but nor do I want to invite any!
I'm interested in the addition of the sugar. Is it for taste, or for the pH? I get the salt and citric acid. Or something else? I recently canned some black current jam, so I'm interested in trying my hand at canning tomatoes.
Thank you for your useful blog.
Yes, I am interested in the "why" of adding brown sugar as well. This Sicilian does not like sweet red sauce. I have fond memories of summer days in the "basement kitchen" processing tomatoes with my mom and any given aunt. Good stuff. I have not canned my own since we never seem to get enough yield so I usually make a quick marinara but I would love to grab a bushel and do this - without the brown sugar if it's not a necessary ingredient ;-)
The brown sugar doesn't alter the taste. That amount isn't nearly enough to make the sauce sweet, it just cuts the acidity. You can leave it out and the canning instructions and recipe will still be safe. ~ karen!
Thanks Karen!
Please just send me a jar! xo
I used to do all this. Now I just vacuum pack the whole tomato’s. When I need some sauce then I take a bag out of the freezer and into the vitamix it goes. Seeds, skin, all of the nutrient rich stuff gets pulverized and into my sauce. So much easier, and leaves me time do do roasted red peppers instead.
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?
Using the tomato press is the very best thing I ever did when I had a big garden. It does work just like you said - mine was aluminum from the hardware store and cost around $40 about 40 years ago - oh, gosh that sounds like a long time ago - I just realized how long ago it was. I gave it away when I moved into town and have wished I had it ever since. I put up enough tomato sauce to last a year and used a big jar several times a week! Usually planted 100 plants. Great advice and exactly how I canned the sauce back then. You are so right, as usual?
One trick I learned to get thicker, less watery sauce -- rough chop tomatoes, throw them in a stock pot and cook for about 30 minutes. Put in the fridge overnight. The next day, there is tons of juice that can be strained off and saved for another use. Then run the tomatoes through the press and out comes yummy, thick sauce. I have a huge garden, but rarely enough to do massive batches, so I do it this way in batches, freezing it as I go. So handy to have on hand.
What is the brand name of the strainer you are using? I've been searching the web and don't see one that looks like it. All metal ones seem to be TSM or Squeezo. While Victorio seems to be a fave, it looks like it is plastic.
I hate to say it Linda but I don't know! It's now relegated to the back of my basement because 2 years ago I finally broke down and bought an electric one and it's great! It was on sale for around $180 at my local grocery store. I've found it on Amazon but it's almost $250 there. It's made in Italy and is much easier to use than the hand grinding one I have. If I find it in the basement I"ll let you know the brand of the hand operated unit. ~ karen!
Karen,
I think we found your hand crank model online. I believe it's a Tre Spade. They have two models. The smaller one is Model - BT. Not sure what the model # ofthe one like you have is but the hopper is available in stainless steel also. I thought I'd like to have the other screen attachments also - just in case :) but I'm not sure they are available with the BT model. I can't find any info on them. Are you interested in selling yours?
I have the KitchenAid attachments mentioned by one commenter, but the press is what I use to process tomatoes. Mine is about 30 years old now and still doing it's job well. Hand-cranked, but I only do a couple of canner loads at a time, from our garden.
I have a Victorio strainer with the tomato and salsa screen that I tried to use last year to make salsa, but I felt like I was just turning my tomatoes into juice. What tips do you have for using a press? That was my first time and I was intimidated, to say the least.
Hi Marek - I have to be honest with you here. I have no idea what the salsa screen is, LOL! I've never even heard of one of these tomato presses being used to make salsa. They're normally used to press the tomatoes, separating the juice and pulp from the seeds and the skin. So, sadly I can't help you with your salsa dilemma, but hopefully someone else can. ~ karen!
Karen: I grow my own tomatoes on our farm and have been canning for years. I put them whole into a food processor and then cook up batches of pasta sauce using Barbara Kingsolver's recipe (yes, the famous author). I follow it exactement. It's fabulous with all her other ingredients and I can't recommend her recipe enough. However, I want to can just plain tomatoes (for soup or other uses) but find that including the seeds and skins makes the plain sauce taste a bit harsh/acidy. (I'm not talking about ph canning levels, just taste). I assume that a tomato press removes the skin, and thus the remainder sauce is 'sweeter'. Is this why folks use presses? Also, what are your thoughts on an electric press. Thanks so much for a very helpful blog!
Hi IslandFarmer - I'll have to look up that recipe. I assume it's in Animal Vegetable Miracle? The reason I use a press is because it does indeed remove all the seeds and skin of the tomatoes. It makes a perfectly smooth, clear tomato sauce almost like tomato juice. I use it for everything I need to add a tomato based liquid like soups, chilis, pizza sauce, spaghetti sauce, etc. I also cook tomato sauce with whole tomatoes, but this pressed tomato sauce is my stape. I use a hand press, but if you can afford it the electric presses are supposed to be fantastic. And fast! ~ karen!
Sue bought an attachment for her Kitchen Aid that we used for the first time this year and it works great! If you have a KA, for fifty bucks this is a must have.
https://www.kitchenaid.com/countertop-appliances/stand-mixers/attachments/p.fruit-and-vegetable-strainer.ksmfvsp.html
Yup! I have to agree. Bought my Kitchenaid mixer just so u could get this attachment. It is a thing of wonder!
First- you are HILARIOUSLY awesome. I think I spent about 2 hours last night perusing your website and just laughing- thank you! I needed a good laugh! i actually found you on a search for canning chicken stock- i used your method! Made so much more sense to me than others. You mentioned ( I think ) in that post that you can diced tomatoes also? Do you have a post on that on your site? I haven't come across it yet, if you do. I started canning last year and attempted diced tomatoes and I was less than thrilled, to say the least, at my results. They taste fine, but they are too soft and not the chunk that I was hoping for. How do you do yours? Thanks so much!!!!!
I'm glad to know that someone else thinks that canning their own tomatoes is totally worth it!! Only mine don't make it 2 years cause I give them away as gifts!!
I didn't see this addressed but for people who don't regularly think of quantities in bushels that's a bit over 50#s of tomatoes. I just wanted to throw that out there for perspective on the total awesome insanity of Karen.
and I have bushel envy. Don't think I've ever seen them sold that way around here.
We have owned both a Victorio and a Sqeezo and liked both. If you don't like the squirts you sometimes get from the strainer, fashion a shield from a plastic bottle so that it fits right over the strainer cone. Mine was made from an empty coffee creamer container.
Don't be afraid of canning. The canner isn't going to explode since it has a pressure relief valve. Your canned jars of tomatoes are safe from power outages, unlike frozen packages that will mush if your freezer is off for too long. The sight of the jars of canned produce is also very satisfying.
We actually have two canners so while the first one is cooling, the second is on the stove building pressure. The whole process is a team effort and a good way to build relationships. Find someone with a canner and get together for a session.
I attempted to use a Victorio last year but I felt like I was making more juice than getting strained tomatoes. I have both the tomato and the salsa screen and I was trying to make salsa. Does it make an insane amount of juice? I felt like I was doing it incorrectly and I'd like to try it again this year, successfully this time.
Thank you Evalyn! I'm off to buy another rack or separator. I do have several books on canning but none of them addressed the problem of keeping jars upright.
I decided to skip canning this year as I still have a good stock of everything but looking at pictures of filled bottles makes me wish I had something to stack on my counter.
Eva - Don't be too jealous. I'm still looking for spots to store it all! ~ karen
Jo: put another wire rack or seperator on top of your jars, then put a larger jar, filled with water, but without a lid, on top to hold it down. Whatever you use as a weight needs to be heavy enough to hold the jars under the water yet let the water circulate. I use a jar with a ring to protect the edges, but no sealer. I also use water filled jars to take up spaces in the canner so the full jars don't rattle against each other or move around in the canner.
I would like to make a recommendation: Everyone who is interested in canning, please by a good canning book. My bible is the Kerr/Ball blue book, which I found next to the lids at my local Whatever Mart. It has everything about canning, freezing, preserving and even receipes. The new edition is actually yellow, but never mind that. Also, if you have access (in the US) to County Extention Service, they have people there who are just waiting to help you out. Call them, make them feel appreciated. Canning is not difficult, but it requires attention to certain details.
Evalyn, thanks for your post. It is a great idea for holding down little jars, and your recommendation to process from the Ball book or the USDA approved So Easy To Preserve, and to check with the local county extension service is right on target.
Just an FYI. Don't forget to update your Ball book every few years or so. The recipes DO change, as well as the timing, etc.
OMG I love you so much right now!! I have had a doohickey sitting in my basement for over 12 years. My mom gave me all her old canning stuff, but didn't tell me what any of it was. Since I didn't can at the time, I didn't care. I just kept moving it. I've been canning for the last few years and have used most of her stuff, but there was one thing I didn't know the use for. I thought it was a sausage grinder, which seemed odd because my mom never made sausage. Oh, I should mention, that my mom died a few years before I started canning, so I couldn't just ask her.(she was selfish that way. She also died before my daughter became a teenager that drives me crazy~stupid cancer!!) I HAVE A TOMATO PRESS!!! It's old and looking a little sad, but I'm going to clean it up today! I REALLY, really, really wish I'd know this when I did tomatoes last week! I am SO glad I didn't sell this at a garage sale! Thank you, thank you!!
Jonalynn - I love you too. ~ karen
I was delighted to see a segment on canning because I was hoping that someone would bring up a problem that I have. I usually make chutney, red pepper jelly, pickled grapes, etc. in small jars -- 250 ml, sometimes even 125 ml. When I put them in the canner they float! No matter if I cram them into the wire lifter basket and lower them in or put a folded towel in the bottom of the pot and stand them on that. No matter if I cover the tops with 1 inch of water or 2 inches or 5 inches or fill it right up to the top. The jars all turn over on their sides and float! They are slippery and its difficult to lift them out with the jar tongs.
Doesn't this happen to anyone else? Is it just me? It's just me, isn't it?