Canning Roma Tomatoes: Why the Long Processing Time?

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Canning Roma Tomatoes

Today’s Canning Chat question has to do with canning Roma tomatoes. My name is Sharon Peterson, and I am with where you can find home canning tips, tutorials, and online canning classes. Come join me there, and I will help you get your pantry filled.

Video Transcript for Canning Roma Tomatoes – Edited for Clarity

So today’s Canning Chat question is from Kay, who is actually in Manitoba, Canada. Her question: “I’m going to attempt canning my Romas today.” (Romas, meaning a Roma tomato.) “This looks like an easy recipe that even I could do. Is it really 85 minutes to process in a water bath? Why so long? I was sure it was only 20 minutes when I did salsa.”

That is a really good question. Yes, it is the correct time for canning in a water bath. It does seem long, but those directions come from the National Center for Home Food Preservation. That’s the tested method. This is canning tomatoes with no added liquid. You just put the tomato in the jar and push it down so the juice comes out, and it just fills up with its own juice. I’m not adding anything to it.

Keep in mind that there is a difference in processing time. If you just put your tomatoes lightly in the jar and add water, it’s going to be a different time. This is canning tomatoes in their own juice. I will put a link to the recipe down below.

The reason the time seems long compared to canning a salsa, for example, is because salsa has added acid. It’s got tomatoes, usually onions and peppers, and it has added acid, usually in the form of vinegar. That’s what makes it safe for processing for a shorter time in a water bath.

Most of the safety is based on the acidity level of the food. It also has to do with the density and some things like that. But the acidity level is why salsa can be a shorter time and a plain tomato would be a longer time.

I cannot comment on the safety of your particular salsa recipe, because I don’t know what it is. I’m assuming that you’re using a tested recipe. You’ve got those ratios correct. You’ve got the correct acidity levels. So then, yes, salsa is going to be shorter than just canning a plain Roma tomato.

I hope that was helpful. You guys have a wonderful afternoon, and I will see you in the next Canning Chat video. We’ll talk to you later. Bye.

Related Pages:

Quart jars filled with tomatoes.
Wiping rims of jars filled with tomato pulp.
Fresh tomatoes floating in a sink of water.

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Page last updated: 7/9/2021

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