Canning Tomatoes

September 1, 2010

Many a summer growing up my dad would plant a large number of tomato plants in the garden. When the first frost was upon us, we would pull the family together, gather our harvest, and can! I remember one year dad pulled me out of bed because there were large snowflakes coming down and the plants were heavy with fruit.  That day we lost a microwave and gained 105 quarts of tomatoes. Needless to say, he plant many tomatoes the next year!

Now that I'm all grown up and still canning, I get a lot of requests for how to do it. Rarely a time goes by that we don't have someone in the neighborhood or from church there helping us with the task so they can learn the process too.  These are wonderful memories and the experience always brings us closer.

Here's the process:

First you need to own this book, or one like it.  You can usually find it at the grocery store along with the canning supplies. It runs about $5.00.  It is your canning bible and will take you through the process step by step.

At our house, you need this stool.  Both Derek and I came from parents who got their kids involved in canning. Derek remembers his mom using his little hands for reaching down in the jars and turning the peach halves the right direction. We can truthfully say that nearly every jar of applesauce we have ever canned has been filled with apples smashed by Tanner. Canning is a great way to instill hard work!

Each fruit is a little different to can.  Some you blanch, some you don't.  Some cooks longer than others.  The canning book will tell you what you need to do.  Tomatoes are a good example of the process though.  Start with washing the fruit.  I do this by putting the tomatoes in a bath in the sink.  I don't use any soap or scrubbing, just rinse them here.

While you are rinsing, get a large pot on the stove one third, to half full with water and bring to a boil.  Once the water is good and hot/boiling, transfer some of the tomatoes into the hot water.  you want the tomatoes to be submersed in the water.  That will tell you how many to put in your pot at a time. 

Leave them in the hot water for 30 to 60 seconds or until the skins start to crack on the tomato. (Often you'll not see so many cracks as the skin just swells a little and gets lighter in color. Don't worry, you'll do enough batches of these, that you'll get good at recognizing when they're ready to skin!)

The purpose of this step is not to cook the tomatoes, but rather prepare them for skinning.

Once they start cracking, pull them out and place them in a bowl.  Quickly start peeling the skins off and coring the tomato.  If you want your tomatoes cut into pieces, now would be the time to do this. 

Once they are skinned, place them in jars. We usually get the jars pretty full, then use our knuckles to shove them down deeper. you want more tomatoes and less dead space in the jars. You can fill the remaining portion of the jar with some warm water if you like, though we usually get the jar full enough that we don't need to. The canning book will tell you how much lemon juice and salt to put in.

Use a long slender knife, or spatula to run down the inside of the jar.  (See next picture.) While in there, tilt the jar in different directions to help get out any air bubbles that might be trapped inside.

Speaking of jars, my first recommendation if you are going to invest in jars is to purchase wide-mouth ones. They just make life delightful.  Narrow mouth jars make it tough to get your hands or your cooking instruments  down inside.  (You see narrow mouth below.) Also, in preparation for canning, fill your dishwasher with your jars and run them through a cycle.  then when you are ready to use them, pull them out while they are nice and hot and ready to use. Keeping everything hot makes a difference in the canning process.

While you are preparing your tomatoes, you should have a small saucepan on the stove running on low.  Put your clean, new lids in this and bring them to an almost boiling temp. You can see two of the canning tools you should own here. You can buy these at the store in the canning section.  The blue stick in the picture has a magnet on the end used for pulling the lids out of the hot water.  The clear stick is for getting air bubbles out of the jars.

Once your bottles are full of tomatoes and you've added your lemon juice and salt, take a clean, dry cloth to the rims of the jars and place a metal lid and ring. Screw on snug, but not overly tight.

Once you have 7 or 8 jars filled, you can put them in a large canning pot for processing.  If you have a flat top kitchen stove, I hear you can ruin it canning, so be careful if you decide to process your jars on them.

We use our camp stove and do the process outside as you can see here. It works out fine and keeps the heat out of the house. For tomatoes, you don't need a pressure canner, which is the pot you see on the left, but it certainly comes in handy to have two pots going at once!  You'll want to fill the pots about half full and have them at a full rolling boil before you place the tomatoes in them. Start the processing time once you arrive at the full rolling boil again.

Check your book for process times, then use this handy tool to pull them out of the boiling water bath. We like to use a "breakfast-in-bed" tray lined with a towel to carry the bottles.  Be careful as the bottles are very hot!

After pulling the bottles out, you may be tempted to touch the lids. (Especially the kids!)  Don't!  As the temperature decreases, the lid will pop down on it's own and seal the bottle.  It is rewarding to hear the frequent pop of the lids while you are cleaning up or still in the thick of canning! Check the lids 12 to 24 hours later.  Any lids that haven't sealed at that time you can either put in your fridge and enjoy soon, or try to reprocess.

Keep in mind when you are handling the jars that they can easily crack and break. It is not uncommon to have this happen, so don't get discouraged.  I would, however, try not to process jars unless the pot is full or nearly full. The boiling water will otherwise throw the jar around too much. Sometimes you may end up with a half batch to process.  I'll fill a few jars with water and place them in the boiling water bath along with the last few tomato jars just so I can keep things from jostling around too much.

A day or so after your canning is done, unscrew the ring and carefully wash each bottle before storing it away.  You can store your bottles with or without the rims.  Be sure to take a permanent marker and write the contents and year on the lid.  You'll be glad you did! 

Enjoy all your hard work!

ps: Salsa is another fun way to can your tomatoes!  Look up some recipes online, or make up your own.