Canning Basics

I want to begin by stating that this post is long, but despite its length, it is not intended to explain everything there is to know about home canning.  It is only meant to provide information about the basics of canning.  There is much more information available in books and online than I have time (or energy) to put into words here (check out my resources page).  That being said, let's get started...

Methods of Canning

There are two basic methods of canning.  The first is canning using a boiling water bath.  This type of canning is successful with high acid foods only.  Think fruits, pickles, jams and jellies, and some tomato products.  When using the boiling water canning method, hot jars of food are submerged in a pot of boiling water and processed for a predetermined amount of time (found in your recipe).  Once the jars are removed, the lids create a seal making the jars shelf stable.

The second canning method is called pressure canning.  It is used primarily for low acid foods like vegetables that have not been acidified through pickling.  This type of canning employs a special pressure canner which allows the food in the jars to reach higher temperatures than they could otherwise reach in a boiling water canner (making them safe for storage). 

On this blog, I will primarily be using the boiling water method so the rest of this post will address that method only.   

Essential Canning Tools

Boiling water canner-  a pot large enough to hold several jars with room for 2 inches of water above  
    the jars (you can use a special pot made for canning or another large pot of your choice)
Canner rack-  a rack is useful to have in the bottom of the canner.  If you are not using a pot that came  
    with a canning rack, you can line the bottom of the pot with canning rings to get the same effect.
Canning jars, lids, and rings-  jars should be made specifically for home canning.  Jars come with two
    piece lid and ring sets.  The rings are reusable, but the lids should be new each time you can. 

Very Helpful Canning Tools

Jar lifter- helps remove hot jars from hot water
Magnetic wand-  helps remove canning lids from hot water
Canning funnel-  helps you put food into jars without making a mess (or burning yourself)
Chopstick or nonmetallic spatula-  helps you free air bubbles from inside jars before putting the lids on
Ruler or headspace measurer-  helps you measure precise headspace which is the space between the   
    top of your food and the top of the jar

Boiling Water Canning Steps

1.  The first thing you need to do is sterilize your jars.  This can be done in one of two ways.  You can  place your empty jars inside your canning pot, fill the pot with warm water, and bring it to a simmer.  Allow the jars to remain in the simmering water until you are ready to fill them.  Alternately, you can place your jars in a dishwasher, run them through a cleaning cycle, and then keep them on the heated setting until they are needed.  I usually use the dishwasher, but if I am only canning a small batch (or my dishwasher is full, as it so often is) I use the canning pot.

2.  Next you need to prepare your lids and rings.  Place the lids (the flat pieces) in a small pot with warm water and bring it to a simmer.  This sterilizes the lid, but it also softens the compound on the bottom of the lid which helps it seal to the jar.  The rings do not necessarily need to be boiled, but you do need to wash them before using.

3. While the above two steps are happening, you can prepare your recipe.   Obviously, you should take into account how long your recipe takes to determine when you will need your jars and lids.

4.  Ladle your food into hot, sterilized jars.  Make sure you leave the amount of headspace required in your recipe. Headspace is the area between the top of your food and the top of the jar.  You should use a ruler or headspace measurer and be as precise as possible.  Your recipe will tell you how much headspace to leave.  A general rule of thumb is that jams and jellies need 1/4 inch while pickles, fruits, tomatoes, and condiments need 1/2 inch.

5.  Free your bubbles.  Run a chopstick or small nonmetallic spatula between the side of the jar and your food to free any air bubbles that may have gotten trapped when you were filling the jars.  This is not just for looks.  Leaving air bubbles can interfere with the sealing of your jars.  After removing bubbles, check headspace again and add more food as necessary.

6.  Wipe the rims of your jars.  Leaving food residue on the rim can cause seal failure.

7.  Once your jars are filled, use a magnetic wand to remove a lid from the hot water.  It is now time to close the jar.  Center the lid on the jar.  Place a ring over the lid and tighten only until "fingertip-tight".    Tightening a jar too much will not allow the air to escape and will interfere with the jar's ability to seal properly.

8.  Place your hot, filled jars into the rack inside your boiling water canner.  Slowly lower the rack into the boiling water, replace the lid, and allow the jars to boil for the amount of time specified on your recipe.  The water should come 1-2 inches above your jars.  You should start timing at the point that your water returns to a boil.  If at some point, your water stops boiling, you should start the processing time over again.  When the time is up, turn the heat off and allow your jars to sit in the canner for 5 minutes.

9.  Carefully, using a jar lifter, remove your jars from the hot water onto a towel.  Allow them to sit, undisturbed, for 24 hours.  This gives the seal time to activate properly.  You will probably hear the "pinging" noise that the jar lids make as they pop down and seal.  After the 24 hour period, check the seals to make sure that middle of the lid does not flex when pressed gently, and store your jars (preferably with the rings off).

10.  Hoard your lovely jars until you just can't take it anymore and are either forced to open them yourself or give them as gifts.  You will be so surprised at how much joy you can get just by walking by a cabinet of colorful jars.  I know I sound weird just saying that, but just you wait and see!