How To: Canning Diced Tomatoes


We’ve had a plethora of tomatoes in our garden this year, so many in fact, that I decided I wanted to can them. We still had several cans of tomato sauce in our pantry from the last time I canned so I decided that was out of the question. I thought about what type of tomato products I use most during the winter and settled on diced tomatoes. I tend to use these in Chili and other hearty recipes throughout the winter so in order to save a little bit of money l decided this was what needed to be canned.

The first step to canning fresh tomatoes, no matter how you will be doing it, is to blanch and skin all the tomatoes. To do this you need to make an X at the bottom of the tomato, then blanch it. You will need to blanch it for about 60 seconds. After this immediately plunge it into ice cold water and the skins should just fall away. If you would like to read more in depth on the blanching process check out my previous post on How To: Blanching Veggies.

You will also need to begin prepping the canning jars and lids. Because of the acidity in tomatoes you can water bath can them. If you are new to the canning process read my post on How To: Water Bath Canning.

I chose to use the Hot Pack method of canning. This requires a pot of boiling water on the stove while you’re dicing. After you’re done dicing the tomatoes you are ready to pack the hot jars. Remove the jars from the boiling pot. Put in ¼ Teaspoon of Citric Acid in the bottom. Fill the jars with the diced tomatoes leaving a ½ inch headspace. Then cover the tomatoes with the boiling water. Place the lid on the jar and tighten the band to fingertip tight, then tighten again.

Place the prepared jars in the water bath canner. Process them for 45 minutes with the lid on. Then remove the lid and process them for another 5 minutes. Remove from the boiling liquid and place on the counter in a spot where they won’t have to be moved for 24 hours. Let them sit and cool. If you find that any jars did not seal you can actually process them again if you catch it within 24 hours. Otherwise put the unsealed jars in the fridge and use within a week. The sealed jars you can put in the pantry for storage.