Roma tomatoes are also known as Italian or plum tomatoes. With their prolific yields of meaty, sweet fruit, they make the ideal tomato for sauces, canning and freezing. And unlike many vegetables, tomatoes are actually more nutritious cooked than raw. If you’ve never preserved tomatoes before, you’ll find the process quick and surprisingly simple. Read on to learn everything you need to know to can or freeze Roma tomatoes.
Canning Roma Tomatoes
Because Roma tomatoes are slightly acidic, they may be safely processed in a water bath canner, rather than a pressure canner. You’ll need about 3 pounds of tomatoes per quart jar or 1 ½ pounds for each pint. Don’t forget to peel the tomatoes. Any bits of peel remaining on the fruit become tough and stringy in the jar. Here are the step-by-step directions for canning tomatoes:
- Wash fresh, ripe tomatoes. Avoid those with cracks, spots or soft spots.
- Place the tomatoes in a pot of boiling water for 30 to 60 seconds, or until the peels start to crack. If you have a metal colander basket, place the tomatoes in the basket and drop them in the pot so you can easily drain them.
- Use a paring knife to slip off the loosened skins. Cut out the green stems and the cores. Leave tomatoes whole, quarter or dice them.
- Warm jars in a pot of hot (but not boiling) water until they are ready to be filled (this will prevent them from breaking when they are immersed in boiling water later).
- Place the prepared tomatoes in the hot quart or pint jars. Add 2 tablespoons bottled lemon juice or ½ teaspoon citric acid to quart jars. For pint jars, use 1 tablespoon bottled lemon juice or ¼ teaspoon citric acid. The lemon juice or citric acid serve two purposes. First, they keep the fruit fresh and preserve its bright color. More importantly, though, they slightly acidify the tomatoes, ensuring a safe canning product. Citric acid is a fine white powder available in bulk at natural food stores, where it is very inexpensive. You can also find packaged citric acid in the canning supply section of most grocery stores. In general, citric acid is more convenient and less expensive than bottled lemon juice.
- Press down on the tomatoes so that the juice fills the jars, leaving ½ inch headspace. Add 1 teaspoon salt to each quart jar or ½ teaspoon salt to each pint. If you prefer, you can omit the salt.
- Remove any air bubbles by stirring with a plastic spoon or spatula. Wipe the rims with a damp cloth and place the seals and rings on the jars, tightening the rings securely.
- Set the jars in a water bath canner filled with water. Place the lid on the canner and bring the water to a boil. Continue boiling pint jars for 40 minutes, quart jars for 45 minutes.
- Remove the jars from the canner with a jar lifter and place them on a towel on the counter top. Don’t touch the jars or rings. Allow them to cool overnight. Press on the lids to make sure the jars have sealed. Wipe the jars clean and store them in a cool, dark place.
Freezing Roma Tomatoes
Freezing Roma tomatoes is even simpler than canning them because you don’t have to remove the skins. Instead, you’ll puree the tomatoes for use in soups, marinara sauce or fresh-tasting salsas. Here’s how:
- Choose firm, ripe Roma tomatoes without blemishes or cracks.
- Cut out the green tops and the cores. Quarter the tomatoes or leave them whole.
- Cook the tomatoes in a pot of simmering water until soft, approximately 15 minutes.
- Drain the tomatoes and process them through a food mill or food processor until pureed. You can leave them slightly chunky or puree them until completely smooth. Add salt to taste if you like, or leave the tomatoes unsalted.
- Ladle the tomato puree into quart or gallon zip-top freezer bags.
- Remove as much air as possible from the bags and lay them flat in the freezer. Once frozen, you’ll have a thin, flat product that takes up much less room than freezer boxes. Stack the bags one on top of each other for convenience.
- To use frozen tomatoes, thaw them in the refrigerator overnight or set them on the countertop for an hour.
Want to know more? Here are a few resources on preserving Roma tomatoes:
Canning and Freezing Tomatoes from the Iowa State University Extension.
Complete Guide to Canning from the National Center for Food Preservation.
By Julie Christensen
When she’s not writing about gardening, food and canning, Julie Christensen enjoys spending time in her gardens, which includes perennials, vegetables and fruit trees. She’s written hundreds of gardening articles for the Gardening Channel, Garden Guides and San Francisco Gate, as well as several e-books.
You don’t mention semi-drying which enhances the flavour far more than freezing. Cut into eighths then dehydrated overnight gives a far more intense flavour. Either refrigerated packed into jars or otherwise in oil with salt and a big clove of garlic, can be kept in the larder. The oil is outstanding in salad dressings and pasta dishes.
Marion Whitaker says
Do you peel – core – remove seeds?
I want to do this now?
Josh C says
I’m new to canning and freezing and going to start this spring summer.
What is the shelf life of canned and frozen items like this?
When I have an abundance of tomatoes in my garden, I just bring them in , give them a rinse, dry them and place into containers or ziplock bags and freeze them whole. To use them, I just thaw them out. What I will change from now though is that I will core them first and then freeze.
Do you have a video on canning vegetables
You can look up how to videos on YouTube.
Rhea Garcia-Creekmore says
I will be canning tomatoes for the first time. I notice a lot of recipe/instructions say to seed the tomatoes. Do I need to seed Romas? I will most likely be canning sauce, and salsa. Thank you!
Denis Maillet says
I leave the seeds
Valerie Stevens says
Should tomatoes stem side up or down on the counter?
Scott Shelley says
When I take my tomatoes from the boiling water the bottom inch of the jar looks like water. Is that normal?
Garret VanDeWeert says
No problem with water in the bottom. Some of mine have, some not. Enjoy your tomatoes!!! If you are making a sauce or need to thicken, you can drain it off. For soup or such, just dump it in the pot and use it. I sometimes drain or collect water from tomatoes before I can them, save the tomato water and can that separate if I have space in the canner. Good drink in the middle of winter and you want to be reminded of what a good tomato tastes like.
Can I use a pressure canner for Roma tomatoes or do I have to use a water bath or freeze them?
Garret VanDeWeert says
Either works fine if your tomatoes are acid enough. The cutoff point is 4.6 pH. If they are higher (lower acidity), add lemon juice or acetic acid per instructions or pressure can. If lower, you can safely water bath. Most directions don’t assume you know how to use pH test strips and just recommend adding lemon juice and pressure can as a catch-all solution. I test, then I know what I’m doing.
Aileen Vaughan says
You suggested 1 lb tomatoes for canning a Quart and 1 1/2 lbs for pint. Does that make sense? Isn’t the pint less? Do you 4 pint jars?
It says above to use 3lbs per quart and 1.5 per pint.
Pat mills says
Will i put the jars completely submerged when canning in pot of water, also how tight to tighten lids before you put in water.
Thanks for any advise
I just finished water canning 25 LBS of vine ripe garden roma tomatoes. I boil water and submerge clean tomatoes for 30 seconds. Remove to bowl. Peel and slice in half. I poke my finger into the seed/ juice sack of the tomatoes. Do this over a mesh strainer with a bowl underneath to catch the tomato juice. Place halved, seeded tomato on cutting board and destem. Keep in half or cut slightly. Push down and heavy pack the tomato meat in clean canning jars with fresh basil, citric acid and salt. Push down on the tomatoes with a spoon and get as much meat in as possible. Leave no air pockets. I top off the jars with some of the juice from the bowl (under the strainer, throw out the seeds).
I do a separate few jars with just the juice. Don’t waste the juice and your sauce will not be filled with seeds.
Fully submerge jars with at least 1 inch of water over the top of the jars. Tighten, but not fully the tops. Boil 45 minutes for quart jars.
I’m new at this. Canning tomatoes that is. So you can use spices as well. When your cannig them ? Does the Basil have to be fresh?