How To Use A Pressure Canner

If you want to learn to can your own food, but have no idea how to use a pressure canner, never fear!

Pressure canners are actually quite simple and, contrary to what you may have heard, safe. 

A few weeks ago, in the article canning 101, I gave a list of things you might need to get started canning, and a pressure canner is definitely on that list. 

This is a really detailed tutorial on how to use a pressure canner with fifteen different steps to the process. Don’t worry, though! It’s not that complicated. Imagine if you wrote step-by-step instructions on how to make spaghetti. Pretty lengthy, eh? And yet, I bet you don’t really give the process a second. 

• Body
• Inner rack
• Lid
• Rubber gasket (there are gasketless models which are highly recommended, but quite expensive)
• Weight or “jiggler”
• Rubber safety valve

I find that a 16-quart canner is a really nice size to work with. It holds 7-quart jars, or 10-pint jars, which is a large enough number that you can get a fair amount of food put up with each batch, but not so large that it’s difficult to move around when you need to.

The rack will fit into the bottom of your canner to protect your jars from direct heat, which could cause them to crack or even shatter. 

With most pressure canners, the lid is fitted with a rubber gasket to seal in the steam. These gaskets can go bad, but with proper care, rarely do. 

Your lid will lock into the bottom portion of your canner. The alignment of the base and lid should be clearly marked, which makes it very easy to lock.

The safety valve listed above is what makes the canner – you guessed it – safe. See, the fear with pressure canners is that the pressure will build up to the point that the canner will explode. Well, with a rubber safety valve, that’s just not going to happen. In the event of excessive pressure build-up, the valve pops and lets all the pressure out. So you’ll have a mess as all the steam escapes and quickly turns back into water all over your stove and floor, which is inconvenient, but it’s not any worse than having a pot of spaghetti boil over.

I’ve only experienced a pressure overload once. my mom was actually canning something, and the valve that the jiggler sits on got clogged. The safety valve popped, and water spewed everywhere. Fortunately, we were able to find it when we were cleaning up the mess and put it back in.

This vent allows steam to escape during the first part of the canning process allowing the contents of your canner to heat evenly. Otherwise, you could be building up pressure in the canner while the food in the middle of your jars is still cold, which increases your risk of bad bacteria surviving the canning process.

Most canners have a weight that can be adjusted from 5-15 pounds of pressure. As you can see with this little Presto canner, each weight is a separate piece that you stack on. On some canners, the weight is all one piece and is balanced in such a way that the amount of pressure depends on which way it’s turned. They’re clearly marked, so if you get one, you’ll know exactly what I’m talking about.
The weight will be placed over the steam vent.

Now that we’ve covered the various parts of the canner, here’s how you go about using it to can food. Remember, these are instructions for the average canner. There are unique canners out there with unique requirements, so be sure to consult your owner’s manual before proceeding.

1. First, fit the rack into your canner.
2. The next step is to add water. Water is necessary to create steam pressure. How much you’ll need depends on how large your canner is. The 21-quart canner shown here uses 2 quarts. Taller canners with the same circumference also use 2 quarts. If your canner has a larger circumference (which is unlikely),  you’ll need more water, smaller canners will need less.
3. Next, add your jars. Try to them in so that they aren’t touching. This lessens the chance of breakage.
4. Remember to make sure all your lids are on properly!
5. After your jars are in place, it’s time to lock on the lid. First, you need to make sure the rubber gasket is fitted correctly, lying flat in its bed, and not bubbling up anywhere. 
6. Also, make sure your safety valve is fitted correctly.
7. Line up the arrows, and lock in place. 
8. Now it’s time to heat that puppy up!
9. Turn the heat up to medium-high, and heat it up so that steam begins to escape through the vent.
10. Let it steam for 10 minutes.
11. Now place the weight over the steam vent. You’ll find that most recipes use 10 pounds of pressure. Occasionally, you’ll see pickle or jam recipes using 5 pounds and meat or corn recipes that use 15.
12. Keep an eye on your canner as it comes up to pressure, and start your timer as soon as it begins to jiggle.
    Ideally, you should get 3-6 jiggles per minute. If you’re getting more, turn the heat down, just a smidgen at a time, until you get it right. Don’t get too drastic with your temperature adjustments, or your canner may lose pressure and cease to jiggle at all, at which point, the safest thing to do is start your timing over. 
13. After the required time under pressure is up, turn the heat off, or remove your pressure canner. DON’T open the lid! Opening the lid while your canner is under pressure is probably the most dangerous thing you can do. We’re talking steam burns and exploding jars. Don’t do it!
14. Let the canner cool until the pressure indicator, if your canner has one, releases. This is simply a little piece of metal that sticks up when there’s pressure in the canner. Ideally, you can let the canner cool a lot longer than that, but if you’re in a hurry, now you can carefully open the lid.
15. ALWAYS REMOVE THE JIGGLER BEFORE REMOVING THE LID. This is to make doubly sure that there’s no pressure inside the canner. 

Now, just because the pressure has gone down doesn’t mean that your jars aren’t extremely hot, and this is why you still need to be very careful about opening the lid. Extremely hot jars meeting cool air can shatter, so make sure the area is draft free, and cover the jars with a towel as they come out.

Let your jars cool for 24 hours. After this period, you can take the rings off if so desired, and store them.

To wash your canner. 

Take everything apart and wash it in warm soapy water. Pay attention to the rubber gasket so that you don’t stretch it, and make sure to dry it well before you put it away to keep the gasket from dry rotting.

Boom. That’s all there is to it. Different from most modern-day housework for sure, but honestly not difficult to master. It just takes a little practice to get the process down.