At some point in your homemaking journey — whether you’re a cook, gardener, or full-blown homesteader — you’ve probably learned how to preserve food. And for many people, boiling water bath canning is the gateway to all other food preserving.
Maybe it speaks to our off-grid fantasies of being a self-sufficient mountain mama (or mountain man). Maybe it’s because the distinctive pop of the lids brings a sense of accomplishment and joy, or the fact that we end up giving some of those jars away as gifts that brings even greater joy.
I learned how to preserve food just a couple months into tending an edible garden (before I learned how much I actually needed to grow to feed my family). That first summer, I canned 24 jars of tomatoes and 40 jars of jams and jellies. (These feijoa-white peach preserves were one of my first batches in the kitchen, and the first canning recipe I ever posted on my blog. Wild, eh?)
Almost a decade later, I’ve learned some useful tips and tricks for modern-day home canning, and even picked up a few time-saving habits as an ambassador for Ball Canning, America’s favorite mason jars.
Learn from these little nuggets of information I’ve gleaned from their test kitchen, as well as from my own experiences (hundreds of jars later!).
1. You don’t need to warm your lids ahead of time.
I first heard this from the Ball Canning test kitchen a few years ago, and I was floored.
I’ve come across countless canning recipes that tell you to preheat the lids in simmering water before using (to soften the sealing compound for better adhesion), and even Ball’s previous product packaging and older editions of their canning book have recommended preheating lids.
However — straight from the source — this is no longer necessary for Ball or Kerr brand lids.
After comprehensive testing by our Quality Assurance Team, it was determined that it is completely safe to skip pre-warming lids in the canning process. While it is still safe to simmer your lids before use, you should never boil them. Our recommendation (for over 40 years) has always been to simmer (180°F) – but not boil (212°F) – the lids.
So, as far as lid prep goes, all that’s needed is a soapy wash in warm water. Done!
2. You don’t need to sterilize canning jars that will process for 10 minutes or more.
Again, mind blown when I learned this.
Many recipes call for jars to be sterilized before canning, a slightly annoying step that involves either submerging the jars in boiling water for 10 minutes (at altitudes of less than 1,000 feet) or remembering to sanitize them in the dishwasher right before you start.
But, good news! According to the National Center for Home Food Preservation, the go-to authority for all things canning, you do not need to sterilize jars if your processing time is 10 minutes or longer (at or below 1,000 feet elevation).
When the process time for canning a food is 10 minutes or more (at 0-1,000 feet elevation), the jars will be sterilized DURING processing in the canner. Therefore, when process times are 10 minutes or more at this altitude, pre-sterilization of jars is not needed. It doesn’t hurt your product to do it anyway, but it does require additional time and energy and is unnecessary.
Many canning recipes, with the exception of certain jams and jellies, already require at least 10 minutes in a boiling water bath, so there’s no need to sterilize these jars ahead of time.
For jellies that call for 5 minutes of processing time, there’s usually no harm in increasing that time to 10 minutes so you can skip the sterilization.
Note that the 10-minute rule applies to those living at or near sea level, so you will need to adjust that time accordingly if you live above 1,000 feet, per HFP.
If you are processing above 1,000 feet elevation, then you need to consider the altitude adjustments needed to sterilize jars so you use the equivalent to 10 minutes of boiling at 0-1,000 feet elevation.
Note that sterilizing is not the same as cleaning — you should always wash your jars thoroughly in soapy water before using. This was a fact that Ball emphasized when I toured their factory in Indiana, as the jars are made in an industrial environment that produces dust and other manufacturing residue.
3. Frozen fruits make excellent jams and preserves.
In the summer, there’s often a lot of pressure that comes with preserving large amounts of fresh, ripe fruits from your garden, especially if you think preserving always means canning “in season” and right now.
But here’s a secret: You can make delicious jams and preserves with frozen fruit, and no one will be the wiser!
Realizing this simple fact has since saved me from stressing over abundant harvests that I couldn’t keep up with in the kitchen. If I knew there was no way I’d be able to preserve my bounty of fruits within the week (including tomatoes, if their intended final use will be for tomato sauce), I spread them out across a baking sheet and put them in the freezer for a couple hours. (Doing this first keeps the fruits from clumping together in a bag.)
Once they’re solid, I collect them into freezer bags and come back to them when life is a little less chaotic and the weather turns cooler.
Another tip: You can make jam with store-bought frozen fruit as well! So if you’re craving homemade blueberry jam in the middle of winter, this is a great way to go.
4. Chopsticks make great bubbling tools.
Bubbling refers to releasing trapped air bubbles in a jar before sealing it with a lid and band. It’s an important step in boiling water bath canning, as not removing air bubbles can lead to seal failures.
You can bubble your jars with any narrow utensil, and in my canning recipes, I often recommend using a chopstick because it’s the perfect profile and material for the job: long, thin, and usually wood or plastic.
However, I’ve had readers in the past ask for alternatives because they didn’t have chopsticks, and in a pinch, I suggested a butter knife could work if they were very careful using it.
Knives and other metal utensils aren’t ideal because they could potentially etch the glass or cause hairline cracks, thus increasing the chances of jar breakage during processing.
But, if you don’t want to buy another kitchen utensil, look in your junk drawer. Are there any disposable chopsticks lingering in there from your last Chinese takeout?
These wooden chopsticks are typically too flimsy for everyday meals and tend to gather dust in the back of my drawer, but they make great bubbling tools. Rather than throwing them out the next time you end up with a few pairs, set them aside for canning purposes.
5. An electric water bath canner can save space in the kitchen and save your glass cooktop, too.
Canning sessions at home used to mean taking over the kitchen for a whole afternoon, so no one else could be in there at the same time as me.
The kitchen counter would be crowded with jars and flavorings, dirty measuring cups and bowls would clutter the sink, and a behemoth of a canning pot would take up the entire stove, even though it only used one burner.
I never liked how the boiling water bath would steam up the kitchen on the hottest of days, and sometimes for multiple days if I had a lot of canning to do.
Then I discovered this electric water bath canner (while shooting a recipe demo in the Ball test kitchen) and it has changed my entire canning process for the better!
Now, I can move the cumbersome part of canning (the boiling water bath) to the dining table or even outside on the patio, as long as I can reach an outlet. It’s freed up space in my kitchen so my husband can get in there and fix a snack without feeling like he’s in my way, and it lets me relax a little, as I don’t have to rush to clear the stove in time for dinner-making.
Let me tell you that canning outdoors is so much more enjoyable on those beautiful summer days when you can take in some fresh air and sunshine and not feel stuck inside, hovering over your stove.
My electric water bath canner also functions as a massive pot for making soup stock (again, so helpful if you can move what’s sometimes an all-day endeavor away from the kitchen) and keeping party-sized beverages, such as mulled cider, nice and hot.
There’s a spigot on the side for dispensing liquid, which also means you don’t need to lift a heavy pot full of water to empty it.
An electric water bath canner is a great solution if you have a smooth (glass or ceramic) cooktop where you’re worried about scratching the surface, or the manufacturer advises against placing a canning pot on it.
As an alternative — especially if you like the idea of canning outside (or at least out of the kitchen) — you can get an induction burner and induction-compatible canning pot to use as a portable canning station.
The upside to going the induction route is how quickly you can get the water up to temperature for a boiling water bath (usually in half the time!). And, the technology itself won’t heat up your entire kitchen while you’re canning.
6. No canning pot? No problem! Use a stockpot with a cooling rack.
I originally started canning with one of those ubiquitous enamel canning pots, and while it wasn’t bad, it wasn’t great. The interior rack it came with was flimsy, the enamel was prone to denting, chipping, and rusting, and because of all these issues, the pot wasn’t really suitable for heavy-duty, general kitchen tasks.
I later found that using a large stainless steel stockpot with a round cooling rack that fits on the bottom was a much better option. I could use the stockpot for actual cooking (seafood boils, bone broth, and the like) and reuse the cooling rack for its intended purpose (as well as for steaming or holding hot items as a trivet).
This was before I got an electric water bath canner (see my previous tip), and while I primarily use that canner now, the stockpot still has a place in my kitchen because it’s so durable.
7. Don’t store your processed jars with the bands on.
The bands (canning rings) are meant to hold the lids in place during processing (and again when you open the jar). Once the jars have cooled and the lids are sealed, you should unscrew the bands, rinse, dry, and store them. (I corral all of mine in a basket near my other canning supplies.)
Doing so will not only keep the bands from corroding onto the lids and making them hard to get off (it happens, especially if you don’t get to the jars for a while), it’ll extend their useful life because they won’t rust as quickly.
You can reuse those same bands for the next round of canning without needing to buy more. Unlike the lids, which are one-time use only (as far as canning goes), the bands can be used over and over again until they rust or become damaged.
(If you find yourself canning frequently, you might want to consider replacement canning rings, which are made of thick stainless steel that should resist rusting and warping.)
Another reason I recommend removing the bands is to ensure you have a good seal on the jar. If there were problems during processing, you’ll know because gases from bacteria and spoilage will break the seal on the lid. If a band is holding that lid in place, you might not find out for weeks or months (when you’re looking for the jar).
As long as the boiling water bath created a good vacuum seal on the lids, unscrewing the bands after processing will not cause your jars to unseal.
8. Properly canned foods can actually last longer than a year on the shelf.
The general rule with home-canned goods is that a proper vacuum seal, along with storage in a dry, dark, and cool place (between 50°F and 70°F), will ensure a shelf life of at least one year.
The National Center for Home Food Preservation recommends that “for best quality, can no more food than you will use within a year.”
This ambiguous statement can be a little confusing, as many people take it to mean their home-canned goods will suddenly “expire” on day 366.
On the contrary, HFP’s recommendation is based on the quality of the food in terms of texture, color, and flavor, and not how well your jars are sealed.
If your jars have been stored under ideal conditions and the lids are still on tight, they can theoretically keep indefinitely. Those pickles may no longer be as crisp as the day they were canned, and certain nuances of the food (such as a subtle sweetness or spice) may be lost, but they’re indeed edible.
With good canning practices, there’s no reason the jam you made two or three years ago isn’t still safe to eat (and is probably still delicious). As with any food, inspect your canned goods before using and trust your instincts if the smell or appearance seems off.
The problem that some people do run into, however, is that the seals on the lids may fail for one reason or another after a year. This is why you should remove the bands (canning rings) from processed jars before putting them away, as you’ll be able to tell if any of the lids end up popping off in storage.