Canning,  Cooking

How To Can Tomatoes

When it comes to making messes in the kitchen, I am The Queen of Disarray. Sometimes the kitchen partner will come home to layers of dirty dishes and pans, flour in my hair and down the front of my apron, and vegetable peelings on the floor where I seemed to have missed the garbage can every time.

“Whatcha up to?” he’ll ask, trying not to laugh at my disaster. “Oh, just trying out this new thing I saw on Pinterest,” I’ll answer back and continue on my merry mess-making. He grabs a dish towel and starts trailing behind me. The guy is a saint for the number of times he’s cleaned up my chaos. He gets a good dinner. I get to be creative. Together we do okay.

The kitchen partner has cleaned up no greater messes than the ones during tomato canning season. Despite my best efforts, I end up with a grainy red film on everything. It just happens. I’d give it up if it wasn’t for how much we save over buying organic canned tomatoes at the co-op (see my broccoli economics post for an idea of how much home preserving can save), and for how good these tomatoes taste in chili and pasta sauces come February. In this case, the mess is totally worth it. 25 pounds of tomatoes and an afternoon sets us up for great local meals all winter long.

Read how easy canning tomatoes is below and get ready to make your own mess in the kitchen. A winter of local meals awaits you!

Canned Tomatoes – Whole or halves in Boiling Water Pack

1. Prep the boiling-water canner and quart jars. The recipe below is for tomatoes halves – raw packed with water. This means that extra acid is added to each jar to process them at a lower pressure/temperature and still maintain food safety guidelines. There are other ways to can tomatoes, but this seems to be the easiest. If you’d like other ideas or to read more about food safety, check out The Wisconsin Safe Food Preservation Series – Guide to canning tomatoes in Wisconsin. For this recipe, prep a boiling-water canning bath and sterilize quart jars – you will need roughly 1 quart jar for every 2 to 3 pounds of tomatoes.

2. Start with fresh, unblemished tomatoes. Bacteria, molds and all kinds of nasty things like to live in the cracks and bruises of tomatoes. It’s important to pick tomatoes that are evenly ripened and free of any damage or decay. It’s also not safe to use tomatoes from dead or frost-killed vines (they’re lower in acid and may not be safe to can). Besides, why who wants to spend all that time canning anything but the very best?

3.Wash the tomatoes and remove any debris. The easiest way we’ve found to wash all of our tomatoes is to fill up the sink with cold water and dump them in. Give them a good scrub to remove any soil and then take off the stems.

4.Peel the tomatoes. This may sound like a pain, but really saves in taste and time later. To peel each tomato, make an X-shaped slit on one end of the fruit. Dip the tomato in boiling water for 10-20 seconds and immediately place into ice-cold water. Allow to cool for a few seconds and the outer skin should peel away easily. Again, the way to do this is with the kitchen sink. Fill it up with ice water and drop each boiled tomato in.

5.  Slice the tomatoes. Depending on the size of your tomatoes and what your later plans are, leave the tomatoes whole or cut them in halves or quarters. I like a smaller size for soups, sauce, and chili as it seems to cut down on cooking time later. If you’re used to purchasing whole canned tomatoes though, stick with processing them that way.

6. Add in the Acid and Salt. The acid level of many garden tomatoes has been bred lower for easier raw eating. This means they may no longer be safe for canning without adding extra acid to each jar. As a precaution for low pH, add 2 tablespoons of bottled lemon juice to each quart jar (1 tablespoon to each pint). Add in 1 teaspoon of salt for flavor.

7. Pack the tomatoes. Fill each hot, sterile jar with tomatoes, leaving 1/2 inch headspace.

8. Add boiling water. Pour boiling water into the jar to cover the tomatoes, leaving 1/2 inch headspace. Gently tap the jar on the counter (careful to use a potholder as the jar will now be very hot!) or use a plastic spatula to release any air bubbles from between the tomatoes. Air bubbles = places for bacteria to grow. It’s best to have as much of the air replaced by liquid as possible. Check headspace again.

9. Wipe the jar rim & seal. Using a towel, gently wipe any excess liquid or tomatoes that may have spilled on the rim of the jar. If anything is on the rim, the lid may not tightly seal to the jar during processing. Place a warmed metal lid on the jar, adjust with a metal ring to tighten. Repeat for each jar to be placed in the canner.

10. Process the jars. Process each quart jar in the boiling water canner for 45 minutes (0-1000 feet above sea level). Make sure the water has returned to a boil before beginning the time. When the time has finished, remove from the canner and place on a flat surface away from any drafts to cool. Each jar will “pop” or seal when cooled to the proper temperature. If a jar does not seal, refrigerate/use immediately or reprocess within 24 hours.

For additional information on canning (and to support the content on Minnesota Locavore) check out these resources: Amazon Canning Guides


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