Boiling Water Canning Step-By-Step

I’m going to be putting up a number of recipes that can be preserved by boiling water canning in order to be stored on the pantry shelf, so I thought it would be best to have a step-by-step tutorial I can link to for those of you who have not done any canning.

I’m using some pictures from a previous post, Pickling and Canning Asparagus, and adding some general instructions that are the same for different foods.

Canning is not hard, it doesn’t take too much time, and it is safe if you follow USDA general guidelines. Especially if you have a garden or belong to a CSA, you’ll want to use your produce for all kinds of wonderful things that you can’t find in the stores or are expensive to buy (and you are in control of what goes in the jars!).

Fifteen years ago I had never canned before, but I had picked buckets of strawberries and decided to try to put them up in jars. I didn’t have anyone to show me how, so I bought the “gold standard” of canning books, Ball Blue Book of Preserving (found in the canning supplies at the grocery store and at Amazon in my sidebar) and followed the instructions. I was nervous about the timing and cleaning, but it all came out fine. And what a feeling when those jar lids start “pinging” to seal- success!

A little information:

There are basically two kinds of canning (approved by the USDA and tested as safest from spoilage):

1. Hot Water-Bath which involves submerging sealed jars in boiling water for a specified length of time in order to tightly seal the jars. Boiling jars to seal works for high-acid foods like fruit, tomatoes (though some, like paste tomatoes, are less acid than many years ago and it is recommended that lemon juice be added to each jar now), and any kind of pickled food.

2. Pressure Cooker where the jars are enclosed within the cooker for a certain time and at a certain level of pressure. This method MUST be used for low-acid foods like corn, beans, and any meats, stews, etc. This is the ONLY way to can these safely at home and it can be dangerous not to follow directions exactly. Some people use this method all the time and find it the best way to can.

I only tried pressure canning a couple of years ago, and only because I had a good friend to walk me through it. It’s way more nerve-wracking for me, so I don’t do much of it- I stick to freezing my corn, and just use it to can any beans we get (which ain’t gonna happen this year).

Supplies you need:

1. A big enamel canning pot with a metal rack in the bottom. They can be bought for about $10-$15 dollars, and I’m always seeing them at the thrift stores (just not during the canning season!), and you will have it for years, so it’s a worthwhile investment.
2. I’d also invest in a “canning kit” which has all the little things that make canning go smoothly: large mouth funnel, special jar tongs to lift the jars out of the hot water, and a lid lifter. There might be something else they throw in, but these are the essentials. Well, not the lid lifter, but the other two. Oh well, I’m sure you get the idea…
3. You’ll need jars, too, which can be bought by the case at the store. I’ve found it much more economical to look for them at thrift stores and garage sales. They are just pennies each this way. The key is to look the other part of the year and not just when it’s canning season. It’s much more difficult to find them in August, September, and October.
4. The lids and bands that are used with the jars come with the jars if they are bought new. It’s also possible to buy the lids and screw bands in a small box at the store, as well as just the lids alone. The screw bands can be used over and over until they get rusty, at which point they could make the jar not seal. The lids must be bought new each year if you are sealing in a canner to ensure a tight seal. Again, I’ve read where people reuse these, but here’s my take: I’m not going to all this work and time to save $1.50 and not have my food seal properly. Just not worth it to me.

Step 1: gather your produce and equipment.

Decide the size jar you’ll need (here I’m using pints and 12-oz quilted jars), and gather the amount the recipe calls for, or what your canner will hold.

Step 2: prepare your food according to the recipe.

Step 3: wash jars and keep them hot.

While the food or brine is cooking wash the jars using soap and hot water and scrub well. I use an old baby bottle brush which works well so I don’t have to get my hand in the jar. Some people run the jars through the dishwasher which is good, too. I have a hard time planning that well: to have the room in the dishwasher and be able to wait until it finishes the cycle. Do whatever works to get them clean.

Keep them hot so they won’t crack when the hot food gets poured in and they are put in the hot water. There are a couple of options:

• Fill with hot tap water and leave in the sink after washing (this is what I do and is pictured). Since I’m usually washing the jars just a few minutes before I need to fill them, the hot water keeps them hot enough. If it ever takes longer and the water has cooled some, I simply refill.
•  The Ball Blue Book of Canning instructs you to put the jars in the canner with the water simmering while you prepare the food. When ready to use the jars, use tongs to pull them out and carefully dump the water from the jar back into the canner.
• Keep the jars upside down on a towel-lined cookie sheet in a very low oven (100-150 degrees). I have a friend who does this and it’s nice that the jars are dry when you want to fill them. However, even at the low temperature, I’ve managed to scorch a couple of towels, so I usually just use the first option.

The main thing is to keep them warm/hot. I have had a jar of pickles crack in the canner before when the jar had cooled too much and it’s not fun seeing all those cukes and spices floating in the water. I also was trying to save money by using an old mayonnaise jar, which obviously I wouldn’t suggest. They are not made to withstand being used again in boiling water.

Step 4: Fill the canner 3/4 full with water and set on high.

This might be the place to mention that if you have a smooth-top range, you will not be able to use a canner on it. I believe it would damage the top. (UPDATE: I’ve heard from a number of readers that they do can on a smooth-top range and it’s fine – but I check your manual to be sure).

Also, I had some damage to the area around the burner (scratches in the enamel) when I first started and found I could buy a special electric burner that’s a bit higher made for canning. I think it was about $20, but that was 10 years ago. It does work, though, and I haven’t had any problems since.

Step 5: Set the number of lids you’ll need in a small pan and heat in hot water, but NOT boiling.

If you have room on the stove, you can set it to a simmer, being careful not to boil. I usually heat a teapot and pour the water over when it boils.

How much time do they sit in the water? Years ago when I was learning the ropes the boxes the lids came in said three minutes, so that’s what I do and I’ve not had problems. I just noticed that the new boxes I have this year just say “until ready for use.” The Ball Blue Book says for 10 minutes. SO, anywhere from 3 to 10 minutes. Often my lids are in longer than 3 minutes waiting for all the other things to come together, I just use the 3 minutes as a minimum time.

Step 6: Pack the jars according to the recipe (here for pickling)

Use a ladle and the wide-mouth funnel to fill with the liquid. For other foods like salsa, use the ladle and funnel to fill the jars to the specified amount.

Step 7: Check the headspace, which is the amount of space left between the food and the top of the jar.

Each recipe will require a different size space, but usually 1/4″ or 1/2″ and it’s important to have this space to seal properly. And, no I don’t use a ruler every time, just as I was learning and to illustrate here. Once you’ve done it awhile, you’ll know where the 1/4″ or 1/2″ falls according to the threads of the jar.

Step 8 (optional with some foods): With food that has been packed in the jar like the asparagus here, or tomatoes, peaches, etc., run a thin spatula around the edge to get out any air bubbles.

This will sometimes cause the liquid to fall below the headspace requirement, so you may need to add a bit more liquid. This step does not need to be done with foods you ladle in like salsa, tomato sauce or jam.

Step 9: wipe rims.

Use a damp cloth (here an old t-shirt rag from the rag bucket I keep under the sink to use instead of paper towels) to wipe the rim and threads, making sure any food residue is removed.

Step 10: seal jars.

Use the magnetic lid lifter (or tongs) to center the lid on the jar. Screw the band on “finger-tip tight” and no more. Just screw on until there’s some resistance, don’t over-tighten.

Step 11: place jars in simmering water in canner.

Use the special jar lifter (see the rubber ends that hold the jar securely?) to lower each jar into the simmering water in the canner. Continue filling each jar and placing in the canner. When all the jars are added, make sure the water is at least 1″ above the jar lids, adding hot water as necessary.

Step 12: Process jars for specified time.

Turn the heat up to high, place the lid on the canner and bring to a roiling boil. When it boils, set the timer for the specified time in the recipe, and lower the heat to medium-high to keep at a steady roiling boil (with the lid on) for the entire time.

I usually lift the lid once in awhile to make sure the boil is roiling and adjust the heat as needed. Also, if processing a long time (some tomatoes take 50 minutes), the water may need to be refilled (with boiling water from a teakettle) to keep the water 1″ above the jars.

Step 13: Remove jars from canner.

The new Blue Ball Books now have you wait for 5 minutes after the timer goes off, removing the lid and turning off the heat, but leaving the jars in the canner. I guess it’s to pressurize the jars. (Update: I’ve read in one newspaper that this is actually not good, but it’s still recommended, I think – up to you). Because I did this for so many years without this step, I try to remember but sometimes I don’t.

You do want to remove them to a towel-lined space, though, to absorb any water and cushion the jars.

Step 14: Let them sit for 24 hours undisturbed.

The lids will start their “pinging” sound which indicates the lids have sealed. The sound of success!

Step 15: After 24 hours, remove the bands and check that the lids have sealed by pressing the center.

They should be concave and not spring back. Also, try to remove the lids with your fingertips. The Ball Book says “gently” but I use my regular strength because I want the seals to be strong enough that I need a bottle-top opener to get them off.

If some are not sealed, put them in the fridge to use within a couple of months. You can reprocess with a new lid, but I usually can’t be bothered and if it’s a pickled item that would be too much cooking for it anyway.

Even though it seems like a lot, once you get the hang of it, it moves fairly quickly and usually I can be done within an hour.

Ready to can? Start with just one or two things that sound good to get the routine down. I’m sure you’ll be doing more when you realize how easy it is and what a thrill you get from seeing the jars lined up on the pantry shelf. For all my favorite canning recipes, be sure to check out all our preserving recipes!

-Jami