How to Can Whole Tomatoes (2024)

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How to Peel and Prep Tomatoes for Canning

Prep the tomato by removing the stem, washing with water and cutting an X with a small knife on the end. Scoring with an X will make it easier to peel when it is blanched. Blanching is a cooking process in which you dip a fruit or vegetable is scalding hot water for a few seconds and then quickly removed and plunged into ice water to stop the cooking process. When this is done with tomatoes, the skins peel away easily from the meat of the tomatoes.

Start by prepping a large bowl of cold water and ice cubes and it set aside. Next, bring a tall pot of water to a boil. Place the scored tomatoes in the boiling water without overcrowding and blanch for 30 sec to 1 min, depending on the size of the tomatoes. The secret is to watch the skins, when they start to crack and get wrinkled, take them out and place in the ice water bath. This will stop the cooking process and cool them down so they can be easily handled. Remove the tomatoes from the ice bath using a slotted spoon and peel by hand. The skin should come off easily. This may take several batches to complete depending on how many tomatoes you are canning. Use a small paring knife to core the tomatoes after peeling.

Canning Tomatoes Step-By-Step

Prepare the jars – First, wash and sterilize each jar. It is best to use warm jars for canning as to not go directly from cold to hot as to not break the jars during the process. To accomplish this you can place them in clean, tap-hot water until ready to use.

Prepare the lids – In a small pan, over medium heat, place lids and rims to preheat for when we seal our cans. This makes the rubber a little malleable to help it stick to the jars. You must use brand new lids every time. Do not re-use old lids. However, you can re-use the rings that you screw on to keep the lids in place.

Add acidity to the jars – Add 2 tablespoons of lemon juice ½ teaspoon of citric acid (found in the canning section in the store) to each quart jar to keep the acidity high for canning. This will not affect the taste at all, it will just make it safe to can. This step CAN NOT be skipped or missed. If you happen to forget, you will need to go back and add the acidity, and re-process the jars. They cannot be safely canned without the lemon juice or citric acid.

Add tomatoes to the jars – Using a funnel, place and pack the tomatoes into each jar while getting rid of any air pockets during the process. This can get messy but try to pack them nice and tight. Use a knife or spoon and move it around the inside of the jar to remove any air bubbles you can see around the sides. Leave ½ to 1 inch of space at the top of the jar to allow for expansion and to prevent the juices from bubbling out or messing with your seal.

Place the lids and rings – Use paper towel dipped in white vinegar to clean around the edges of the jars. Wipe again with a dry paper towel to remove any moisture from the rim. If there is any moisture in the rim when you place the dip on the top, it won’t seal properly. Add lid and rings and twist until just tight.

Process the jars – Place the jars in the rack of a hot water bath and lower into the boiling water canner pot until completely submerged. Process 40-55 minutes depending on your elevation (see in the recipe below). Remove and allow to cool until the lids are all suctioned down. When you press the top of the lid it shouldn’t make a popping sound.

Pro Tips for Canning Tomatoes

• Always remember to date the jars on the lids so you know which month and year they were canned. This makes it easier to rotate through your jars for maximum freshness
• Want to canned diced tomatoes instead? Diced tomatoes are great for soups and easier to simmer down. Check out our guide for canning diced tomatoes.
• Add a little salt, garlic powder, or onion powder to each jar to add a little flavor to the tomatoes. You can also add a couple fresh basil leaves (rinsed well) to the bottom of the jar for an Italian flavor. When we went to the canned tomato factory in Italy, they added basil leaves to every jar which I thought was really cool.
• Core the tomatoes. This is also mentioned in the recipe. You can can them without coring, but then you have to deal with the tough little cores after canning. It’s just easier to do it before you can.
• You will probably find that the tomatoes and juices will separate after processing. This is totally normal. Just give the jars a little shake before opening to combine or give them a good stir after opening.
• To ensure safety before canning any type of food, review theUSDA Complete Guide to Home Canning.