Introduction: Canning Tomatoes = Summertime All Year Long!

About: I am an artist, educator, tinkerer, and repurposer, err, recycler.
In late summer I try to set aside a Saturday morning to can a dozen or so pint jars of tomatoes. Canning tomatoes does not require a lot of fancy equipment and for one morning's worth of work, you'll have plenty of jars of this beautiful fruit all through the winter.

Step 1: The Tomatoes!

I am lucky to have a wonderful Farmer's Market in my neighborhood, and if you have one in your area, that is the best place to purchase the tomatoes. You can be sure that they'll be local, fresh, and often organic - and you can usually get them for a much better price than at the supermarket.

In my geographic area, tomatoes do not really come into their full bounty until mid August. And when they do, I connect with a local seller, place my order, work out a price and then plan to pick them up the following week. I usually buy a basket of tomatoes which I think is about a half bushel. Always look for fresh, unblemished, and fully ripe tomatoes.

The best canning tomatoes are Roma tomatoes. The are small, oblong and firm-fleshed. As a result, they hold up very well in the canning process.

Once you have picked them up you should plan to can them as soon as possible. My Farmer's Market is on a Friday and I always plan to can the tomatoes the next morning.  No need to refrigerate them - they'll be fine on your kitchen counter overnite.

No matter how many times I have done this I always follow the Ball Blue Book Canning Guide step by step. I encourage you to do the same thing.

Step 2: Gathering Your Equipment

To can tomatoes you'll need:

Ball Blue Book Canning Guide
Kerr or Mason or Ball Brand pint jars (I use wide-mouth jars, they are easier to fill)- for my basket of tomatoes I usually need about 15-16
Lids and rings/bands -  make sure you buy the right size for your jars
Large mixing bowls
Several pots for boiling water
A paring knife and a chef's knife
Measuring spoons and a cup
Tongs for grabbing those hot jars
Salt ( I used Kosher salt for this instructable - but any good table salt will work)
Bottled lemon juice
Clean kitchen towels
Canning equipment - in this case a hot water bath canner

Step 3: Boil Water!

You'll need a pot for the tomatoes and at least one more for the lids. I also have a tea kettle ready in case I need to add more hot water as I go along.

If you have room on your stove you should also start to heat the water in your canner. Be sure to wash it well and fill it only about half-way. Put the lid on and put it on medium to high heat. By the time your tomatoes are packed in the jars, the canner will be ready.

Step 4: Preparing the Tomatoes

Wash the tomatoes in plain water.
Transfer in batches into a boiling water bath for 30 seconds.
Remove and place in a bowl of cold water.
Peel the tomatoes - the skin should pull right off with a paring knife.
After they are peeled, cut them in half and remove the core.

Step 5: Preparing the Jars

Wash the jars in hot soapy water and rinse. Check the rims for nicks or cracks. If you feel a nick in the rim, do not use the jar. It will never be able to form a vacuum seal.

Wash the lid and rings in hot soapy water. Rinse and place in them in a pan of simmering water.

Leave the jars submerged in hot water in the sink. Add more hot water, from time to time, to make sure they stay nice and hot.

Step 6: Filling the Jars

My canner holds about 7 pints, or about half my basket of tomatoes. As a result, I usually repeat this the entire process twice. While the first batch is processing I can get the second one ready to go.

Filling the Jars:
The Ball Canning Guide calls for 1 tablespoon of bottled lemon juice in each pint jar. I add that first.
Then pack in as many tomatoes as you can. I usually pack them in layers - seed side down.
Leave about 1/2 inch of space at the top.
Add 1/2 teaspoon of salt to the top of the tomatoes.
Then add hot water to cover also leaving 1/2 inch of space at the top.
With a clean cloth, wipe around the top of the jar to remove any spillage.

Using tongs remove a lid from the hot water and place on the top of the jar. Grab a ring and tighten firmly.

Step 7: Canning Time!

Once the jars have been filled and lids tightened they are ready for water bath canning. Because tomatoes are acidic, it is perfectly safe to can them this way. I always follow the Blue Book canning guidelines which say to place the jars in hot but not boiling water. Make sure the water covers them by 1-2 inches. If you need to add water, use the hot water from your teakettle. If you have too much water, use a ladle to scoop it out and pour it into another container. Cover and bring to a boil. Once the water is boiling, start timing. Process pints for 35 minutes at a gentle boil. I always boil for 40 minutes for extra assurance.

Step 8: Tomato Goodness

Using tongs, remove the jars from the hot water. Careful because they are very, very hot!
I place the jars on a dry kitchen towel with plenty of space around them.
Let them cool for several hours. As they cool down, the lids start to shrink and that's what creates the vacuum seal. Take a look at the lids periodically and you'll see that the bump in the middle of the lid becomes almost  a little dimple. Then you know they are safe to store. If any jar doesn't seal, store it in the refrigerator and eat soon. The rest of the jars can be stored for many months in a dark cool place.

Yum! Yum! Yum!
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