Friday, September 14, 2012

Canning tomatoes in a water bath canner

Finished jars
There's something special about going to your pantry or cupboard in January and pulling out a home-canned jar of tomatoes for a recipe. You can taste the flavor of summer, and perhaps smell the scent of the hot sun on the tomatoes as you crack the lid open. The effort might be a bit more than you're used to, but the results are more than worth every moment of work.

For the recipe to the stewed tomatoes, please check out my Examiner article on cooking them.  Today we'll be dealing with how you can up the results of your tomato processing. It should be noted that, while it's possible to make stewed tomatoes and can them in the same day, it's often more comfortable to do them on two separate days. Especially at this time of year, the kitchen can get hot very quickly, and each stage of this process takes up a lot of room.

Jar lifter in metal bowl
First, you'll want to assemble all your tools. It's absolutely necessary to have your stewed tomatoes on hand and hot, your jars, lids and rings, a clean, moist cloth, and some hot pads. For the most comfortable canning experience, it's worthwhile picking up a canning kit, which includes a magnetic lid lifter,  funnel, jar lifter (pictured at right), and a plastic or wooden spatula. Some kits also include a lid sterilizer rack, which makes that part a breeze. I also like to have extra kitchen towels on hand, and a large metal or ceramic bowl to catch the drips.

Lids and rings, heating
Add two to three inches of water into your canner pot and put your clean jars in upside down to sterilize and heat them. Bring the water to a rolling boil then turn it down to just a simmer while you get everything else ready. Lids and rings should go into a small pot and be covered with water. Never boil the lids, as it can damage the rubber rings and cause your jars to not seal correctly. A light simmer is more than adequate.

Jars heating up
Have your pot of stewed tomatoes sitting beside the spot you'll fill them at, with the jars in the canner beside that.  This keeps you from spilling tomatoes into your pot of hot jars and keeps your mess and reach to a minimum. Beware; as you remove the jars from the canner, they will be hot! Use hot pads and your jar lifter to get them in and out of the pot. Never put your fingers or hands into the opening of the jar as you turn it right side up, because the hot steam coming out of the jar can and will scald your skin.

Jar with funnel and spatula
Pull out one jar with the lifter and put it right side up in your bowl. Slide the funnel into the mouth of the jar, and put the spatula into the jar itself. The spatula does a two things for you. First, it spreads the heat out a bit more evenly, which isn't as important today as it was in the past, but is still a good idea. Second, it helps keep bubbles from forming in the jar. Before removing the spatula from the jar, move it around a bit in circles then up and down, allowing all bubbles to rise to the surface. This helps create a good seal during the canning process.

Filling the jars
Slowly and carefully begin scooping the stewed tomatoes into the hot jar. The funnel will make this much easier and will keep the mess to a minimum. When you get near the top of the jar, fill slowly. The last quarter inch or so should be liquid, and the jar is considered full when it reaches the top of the rounded part of the glass. Do not fill the jar up into the neck, as it will be too full and may boil over while canning. Wipe the neck and rim of the jar with your cloth, making sure that there are no bits of tomato or spattered liquid there. A little extra vigilance here will mean a better seal later. Don't rush.

The magnetic lifter works well
Using tongs or your magnetic lifter, retrieve one of the lids from your other pot, and let it drip for a moment. Place it gently but firmly onto the rim of the jar, being sure to center it well. Get a ring from the water, and add that on top of the lid, securing it in place. You should only make the rings "finger tight". This means only use your fingers and not the palm of your hand while tightening, and don't try to screw it down very hard.

Ready to be canned
When the lid and ring are secure, give the jar a wipe with another cloth and return it to the canning pot. It should slide right back into the space it left, but this time it will be right side up. Repeat this procedure until all the jars are filled and returned to the pot. An average canning pot will hold seven quarts or nine pints comfortably. I used quart jars for my stewed tomatoes because that's the amount of tomatoes we generally go through in a meal. You may want to use smaller jars for yours. You should always can in jars that are the size you want to pull out of the cupboard to use, so there is no waste.

Jars in the canner
I use my pressure canner as a water bath canner, but there are water bath canners that are sold just for that purpose. There are different sizes of each of these. Mine is 21.5 quarts in size. As a water bath it holds the standard seven quarts or nine pints, but when I am pressure canning I have an option of adding a tray and stacking pints double high, allowing me to pressure can up to 18 pints at a time. The water in a water bath canner should be an inch to two inches above the lids of the jars. If you can, boil water in another pot to add to the canner, to speed up the heating process.

Don't click the lid shut!
When using the pressure canner for water bathing, be sure not to click the lid closed. You don't want to build up pressure when water bath canning! Bring your lidded canner to a boil, then slowly turn the heat down until it reaches a point of boiling without completely rattling the jars around inside. For stewed tomatoes at 1000 feet or less above sea level, you want to process the jars for 45 minutes. You can check processing times online, or pick up a book like the Blue Ball Book Guide to Preserving or Putting Food By for reference. I prefer the latter book, which has information about more than just canning.

When your processing time is over, turn off the heat and let your canner stop boiling. Avoid opening or moving it before the boil stops, as it can jostle the lids and rings, and cause sealing failure. Use your jar lifter to remove the jars as soon as you safely can, and set them carefully on a dry kitchen towel. Let them rest, undisturbed, at least overnight and preferably 24 hours.

There are some tricks to checking to see if the seals are right. Many books (including the ones I mentioned above) will tell you to visually inspect the lids, then press gently on the top of the lid to see if the "button" is popped down. If it is, then your food is properly sealed. However, the act of pressing down can actually cause the seal to break every once in a while, so it's better to use what I call the "ping ping bong" test.

Using a metal tea spoon, gently let the bowl of it fall onto the center of each lid. You should notice that your jars have a "ping" sound. If one or more has a distinctly deeper "bong" tone, it is likely not sealed fully and should be put into the refrigerator immediately. Use unsealed food as soon as possible to avoid spoilage.

Ready to be put away
Sealed jars can be labeled and put away as soon as they are completely cool to the touch. If there is any stuff on the outside of the jar, wipe it down before storing it away. Most people label the tops of their jars, but others have fancy labels they affix to the side of the jar. The choice is yours! Be certain to label them somewhere, though, because stewed tomatoes look a lot like salsa, spaghetti sauce, and even baked beans once they've been in the dark pantry for a couple of months.

No ring, Ma!
Sealed jars can be put away without the rings, if you need them for sealing up other jars. The lids stay on by themselves, held on by the pressure created during canning. Rings are handy to have on hand, though, even if you don't store your jars with them on. If you open a jar but don't use the entire contents, you'll want to put it in the fridge. A ring will hold the lid in place for you.

Rings can also be used in decorative fashion. Some people like to cut a scrap of quilting fabric and put it over the lid, then screw the ring in place. If you do this with in-season fabric, it can be a beautiful gift. Others will use raffia to tie home made labels to their jars. There are places online to print your own labels, either for the metal lids or for the side of the jars. You can also buy sticky labels at most grocery and hardware stores.

Check back next week for information on pressure canning and more. If you have questions or comments, please write to me below. I love to answer questions! You can follow the blog via Network Blogs and Google Friend Connect (see the left hand column for the button).

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