Monday, August 22, 2011

Pressure Canning Tomatoes

Sense of Home Kitchen

I always pressure can my tomatoes, I realize not everyone does and it may not always be necessary. Heirloom tomatoes have more acidity and if you're not sure how much acid your tomatoes have, two tablespoons of lemon juice in the quart will supply the acid needed.  However, I choose to pressure can for a couple of reasons.  First, I use a variety of tomatoes, some heirloom, some not, all have varying degrees of acidity.  Second, pressure canning is so much quicker and puts far less steam into the air.  According to the instructions that came with my pressure canner, if you want to use the water bath method you have to boil the jars of tomatoes for 85 minutes.  We are trying to save electricity by not using our air conditioning accept on the unbearably hot and humid days, adding that much moisture and heat to our house would likely cause us to turn on the air conditioner.  When pressure canning there is only a little moisture added to the air at the beginning and they only need to be kept under pressure for 25 minutes.

I used to think pressure canning was a scary process, it's not.  Just follow the manufacture's instructions carefully and the process goes very smoothly.  You start by placing the freshly washed ripe tomatoes in boiling water for one minute, then plunging them in icy water to cool them so they do not continue to cook.  Take the tomatoes out of the cool water, peel off their skins, core them and place them into prepared jars.  "Prepared jars" means they have been washed in hot soapy water, filled with boiling water and let sit full of the hot water until just before tomatoes are placed in them.

Fill the jar with whole or cut tomatoes and press down to fill all the space with tomatoes and the juice that squeezes out of the tomatoes.  The directions that came with my pressure canner said to add 2 tablespoons of lemon juice to a quart or 1 tablespoon to a pint of tomatoes, whether you are pressure canning or processing in a water bath, not sure why it would be necessary if you are pressure canning, but there you are.  Fill the jars with tomatoes and the directed lemon juice, leaving 1/2-inch headspace, work out the air bubbles with a nonmetallic spatula.  Then wipe the sealing edge clean with a damp cloth and place a new lid (that has been prepared by placing it in simmering water for approximately one minute) on top and screw on a clean band.  Let the jars sit until you have enough jars to fill the canner or until you have used all your tomatoes, such as was the case above with my measly four quarts.

Once all the jars are ready, place them in the pressure canner, pour the amount of boiling water into the canner that the manufacture instructs (for my maximum 7 quart canner, 3 quarts of boiling water is required), add two tablespoons of white vinegar to keep the jars from getting a white film on them, hold the lid toward the light and look through the vent pipe to make sure it is open, and then secure the lid to the pot.  At this point you raise the temperature quite high until a free flow of steam comes out.  After 10 minutes with a steady flow of steam, place the pressure regulator on the vent pipe and watch the pressure gauge.  These are the instructions for my pressure canner, be sure to follow the specific instructions for your canner.

Once the pressure gauge reaches the number of pounds your manufacturer indicates (mine calls for 11 pounds for whole tomatoes) set your timer for the required amount of time (my manufacturer calls for 25 minutes), back off on the heat a little.  Then just watch the pressure gauge closely and increase or decrease your heat as needed to keep the gauge at the required number of pounds.  Don't panic if you see it rise above the number, just turn the heat down slightly and you will see the gauge stop rising and slowly fall.  You don't need to sit and stare at the the gauge, just keep looking back at it while you go about your work.  I use this time to clean up the kitchen and 25 minutes is about the right amount of time to wash the dishes and wipe down the counters, while still keeping a close eye on the gauge.  After the required amount of time under pressure turn off the heat and allow the pressure to drop on its own accord, do not try to cool it down quickly.  The pressure is completely reduced when the air vent / cover lock and overpressure plug have dropped and no steam escapes when the pressure regulator is tilted.  Attempting to speed the cooling of the canner may cause jar breakage or it may force liquid out of the jars.  Again, follow strictly the directions that come with your pressure canner, the directions I mention are just to give you a general idea of what is involved.

The finished product will be beautiful jars of tomatoes preserved for future sauces, chili, stews, you name it, it will be good.  Don't let a pressure canner intimidate you, they are really a simple and safe way to can.  I spent approximately $50 on my pressure canner, it holds up to 7 quarts at a time and throughout the years I have canned whole tomatoes, tomato sauce, marinara sauce, tomato soup, chicken broth, chicken soup, and green beans.  Most vegetables require pressure canning, or pickling if you want to stick with the water bath method.  I have had canned corn, but I prefer it frozen. For fruits, pickles, and jams I use the water bath method.  Plus the recipe I use for salsa has vinegar in it and specifically says not to pressure can, but to use the water bath method, so I do.  Getting comfortable with a pressure canner opens up the possibilities for more local products canned and on your pantry shelves for later use.

I had better be comfortable with my pressure canner I have a lot more tomatoes ripening in the garden,  those 4 quarts were just the beginning.  When we had all those high temperature and high humidity days in July the tomatoes really took off, some of the plants are 5 feet tall and loaded with tomatoes.

Sense of Home Kitchen / Homemade Living / Kitchen and Pantry