If you’re trying your hand at canning for the first time this year, you’re not alone. While it’s not quite as tricky as creating a sourdough starter, there are some important things to keep in mind for health and safety reasons—not to mention for simply streamlining the process—and tips for making everything taste better too.
Canning and preserving seem more appropriate for June Cleaver types than our current 30-minute-meal society. But if everyone’s curing meat and making moonshine, shouldn’t canning also be an urbanite hobby? …We actually wrote those two sentences in 2007, but replace curing meat with baking bread and making moonshine with tending vegetable gardens—or at least regrowing scallions—and it’s just as applicable today. (Of course, the impetus for much of the current wave of DIY kitchen projects is not just a faltering economy, but a global pandemic; it’s as much about staying safe and self-reliant as saving money—and perhaps about finding comfort in the kitchen too.)
While water bath canning in particular isn’t difficult, there are fundamental pointers that may not be obvious to first-timers. And since improperly preserving food can lead to big trouble (hello, botulism), or at the very least a lot of extra hassle, we collected some helpful hints below.
Related Reading: Essential Canning Supplies to Stock Before You Begin
Canning Tips for Beginners
See our Beginner’s Guide to Canning for a basic overview of the process, and our breakdown of Canning and Preserving for more info on various methods, as well as additional canning resources both online and in print. Then check out these tips and recipes:
1. Pick Ripe Produce
Although you’ll be adding sugar, salt, acid, and/or pickling spices to your fruits and veggies that will not only help prolong their life but complement or amplify their flavor, the star ingredient itself won’t get any tastier than when you start out. This may seem obvious, but be sure to pick ripe, great-tasting berries, stone fruit, vegetables, and other raw ingredients or you’ll likely be underwhelmed when you open your jars down the line. You can get away with using slightly overripe fruit for jams and jellies, but overripe produce won’t make good pickles.
Related Reading: 9 Produce Subscriptions You Should Know About
2. Know When to Get Creative
Normally, we’re all for tweaking recipes and treating them more like templates than rigid rules, but when it comes to canning, it’s important to follow the recipe exactly as written; even just adding fresh herbs can potentially throw off the delicate balance of acid, which can make your food spoil much more quickly. Luckily, you can find plenty of creative canning recipes online and in cookbooks dedicated to the subject. And if you just can’t help yourself, see when and how you can safely tweak canning recipes, and what you must never alter.
Not Your Mama's Canning Book: Modern Canned Goods and What to Make with Them, $18.79 from Amazon
This book by Rebecca Lindamood includes more inventive recipes, like cherries in red wine syrup, ginger peach butter, and curried pickled cauliflower.
3. Don’t Use Your Instant Pot for Pressure Canning
Along the same lines, while we usually love finding new ways to use all our kitchen appliances—and while some Instant Pot models actually have a canning setting—the USDA advises against using it for pressure canning recipes. It may be safe to use for water bath canning recipes, but a pressure cooker is not the same as a pressure canner, and it’s important you use the latter piece of equipment for pressure canning recipes.
4. You Don’t Need to Buy a Water Bath Canner
That is, if you already own a large stockpot and a steamer rack, and as long as the pot is large enough to give you proper room; per the National Center for Home Food Preservation, it “must be deep enough so that at least one inch of briskly boiling water will be over the tops of jars during processing.”
Water Bath Canner, $99.95 from Williams Sonoma
This model includes a double-sided rack, tempered glass lid with steam vent, and a built-in temperature indicator.
5. Always Use the Proper Canning Method
If a recipe calls for pressure canning, you must use that method; you can’t decide to use the boiling water bath instead, because the temperature won’t get hot enough to kill all the microorganisms and bacteria. The pressure canning method is used for low-acid food like vegetables (that have not been pickled first), beans, and meat. Water bath canning is appropriate for high-acid food like fruit and tomatoes, as well as veggies that have been pickled.
6. Be Sure to Sterilize Correctly (And Know When you Can Skip It)
Sterilizing your jars is critical—the whole point of preserving food is to kill or inhibit the growth of harmful bacteria, after all. Many resources say you can use your dishwasher to sterilize jars, but that isn’t actually considered adequate (at least not in all cases); to properly sterilize them, they need to be covered by boiling water for 10 minutes. That also means that if your recipe calls for processing the jarred food for at least 10 minutes or if you’re pressure canning, you don’t have to sterilize the jars first. It’s still recommended that you warm the jars, but you never need to warm the lids.
7. Fresh Lemon Juice Isn’t Best
This is another instance where we go against our usual ethos; fresh-squeezed citrus juice always tastes best, but the reason that bottled lemon juice is preferable in canning is that it’s been pasteurized and the pH is consistent. There are some exceptions where you can use fresh lemon juice with no worries, but when in doubt, defer to your recipe instructions.
8. Pay Extra Attention to Pickles
When pickling produce before canning, there are a few extra things to be aware of: you should buy pickling salt (or know which brand of kosher salt and what amount can be substituted in its place); you need a vinegar that is at least 5 percent acid and should never alter the total amount (though you can add sugar to correct a brine that is too sharp). If you’re using cucumbers, skip the waxy grocery store specimens, as the brine won’t penetrate properly.
Related Reading: 11 Pickle Recipes to Punch Up Your Plate
9. Practice Proper Mise en Place
Since canning usually happens in big batches and involves a significant amount of equipment and prep, it’s even more beneficial than usual to get everything ready before you begin. Be sure to read your recipe all the way through, make sure you have the right amount of each ingredient on hand—but also check your supplies. Examine the canning jars for nicks, cracks, uneven rims, or sharp edges that may prevent sealing or cause breakage; check that the lids have no dents and that the sealing compound is even and complete; and check that the bands fit properly. Do this at least a few days ahead of time so if you do find issues, you can fix them before you have a mountain of fresh fruit in front of you.
10. Don’t Overfill Your Jars
Overfilling jars can cause leaks and interfere with a proper seal, so be sure to leave enough headspace at the top—that is, some empty space at the top of the jar between the bottom of the lid and the contents. Each recipe will indicate the proper amount of headspace, so pay attention to that. If you underfill jars, that can sometimes cause sealing issues too, or may cause the top layer of the contents to discolor (which isn’t dangerous, but isn’t ideal). Read more about headspace here.
11. Don’t Forget to Burst Your Bubbles
Similar to the above, when packing your jams and jellies into jars, you’ll want to force out any air bubbles to help ensure the lids tightly seal. You can buy a special tool for this job, but a clean, sterilized chopstick is just as good for banishing bubbles, and a small, flexible spatula also works. Just don’t use a metal knife.
12. Always Check Your Seals
After canning, whether you use the water bath or pressure canning method, check every single jar to make sure it sealed. Allow the jars to cool completely before removing the bands and pressing on each lid; if it has no give and you can’t easily lift it off with your fingertips, it’s good to go to the pantry or in the cupboard. Any jars that didn’t seal properly aren’t safe to store unrefrigerated. You’ll need to empty the contents into a new, sterilized jar and repeat the canning process, or you can simply store the improperly sealed jars in the fridge (and eat the contents within a month or two).
13. Place a Barrier on Your Countertop for Cooling
Placing hot jars on a cool kitchen counter can cause breaks, so be sure to lay down kitchen towels or hot pads wherever you plan to cool your processed jars. (If you hear pinging sounds as they cool, don’t be alarmed; that’s probably just the seals forming and is a good sign.)
14. Don’t Store Jars with the Bands On
Those rings that screw the lid in place aren’t actually necessary once the canning process is complete and the jars have sealed. In fact, leaving them on can make them corrode, which will make them hard to remove later. Taking the rings off also lets you see that you have a proper seal, and that it’s not broken by any expansion of the contents during storage, which could be a sign of bacterial growth; if any lids do come off during storage, throw the contents of those jars away. (You will need the bands for holding the lids in place once you break the seal yourself, but in the meanwhile, you can also reuse the bands for other canning projects. Just toss them once they begin to show any signs of rust or other damage.)
If you’re canning with Weck jars that use rubber sealing rings, glass lids, and metal clips, you can remove those clips once cooled too.
Weck 19.6-Ounce Jars, 6 for $39.95 from Williams Sonoma
An alternative to the usual mason jars.
Related Reading: 12 Clever Ways to Use Mason Jars Beyond Canning
15. You Don’t Have to Can ASAP
If you have perfectly ripe fruit that’s about to tip over the line into spoiled territory but you don’t have time to undertake the whole canning process right now, stash them in the freezer until you do. You can still make them into jam, jelly, or preserves and can them after without losing any of the nutrients or flavor. While this is true of produce in general, veggies with high water content like cucumbers will be negatively affected by freezing so you won’t get crisp pickles later.
Check out the additional resources section of our canning vs preserving guide for plenty more pointers. Then it’s just a matter of picking a recipe to try.
An earlier version of this story was written in 2007.
Header image courtesy of RonBailey / E+ / Getty Images