A Comprehensive Guide to Hot Water–Canning
Canning is one of those old-world skills that feels a little unnecessary until you’re left with an end-of-the-season bumper crop of tomatoes, beans, or other garden produce that you can’t stand to throw away—then, it’s something you really wish you knew how to do. The good news is, it’s really not that hard to learn.
Once you do, you’ll have healthy, safe food for your family that you can store up for the winter, allowing you to enjoy the fruits of your garden all year long.
There are two home canning methods: hot water–canning and pressure canning. Hot water–canning can only be used on highly acidic foods because the acid prevents the growth of dangerous bacteria, including botulinum, which causes botulism. Many fruits contain high levels of acid, and pickled veggies and tomato sauces can be safely hot water canned. As a rule, don’t use the hot water method for anything with a pH higher than 4.6, and always do research before hot water–canning.
We highly recommend visiting the New London Cannery in Forest to jump in on a canning session. They offer their knowledge to the public starting in mid-summer, while guiding you through the canning process with the produce you bring in. They do charge a small fee of $1 per 28 oz. can, and $0.75 per 14 oz. can, but at the end of the class, you walk out with your very own properly preserved produce. It’s well worth it.
In the meantime, here’s a jump-start guide to hot water–canning:
Two Large Pots: To start, you’ll need a big, deep pot with a tight-fitting lid. You don’t have to have an official canning pot, but you’ll need an aluminum pot that’s deep enough to completely submerge your jars with at least an inch of water above the lids. You will also need a second large pot (no lid necessary) to boil your empty jars before the canning process begins.
Rack: The rack keeps the cans in place when boiling and holds the bottoms of the glass jars above the bottom of the pan. If they sit on the bottom, the jars will overheat and crack.
Jars & Lids: Glass jars like the ones made by Mason and Ball come in all shapes and sizes, and you can reuse the jars again and again! That said, you should never reuse the lids; always start with a clean, new lid. You should also never recycle antique jars, store-bought pickle jars, or other collected glass vessels for canning.
Tongs: The jars will be extremely hot when lifted out of the pot, so get yourself a set of canning tongs, which are specially designed to hold onto those jars.
1. Boil your empty jars in the large pot that you aren’t using for canning. The lids and bands don’t need to be boiled, but the jars will need to be fully submerged in boiling water for about ten minutes.
2. While the empty jars boil in the other pot, place the rack inside the canning pot. Then, fill the canning pot with water and bring to a simmer. Keep the simmer going as you complete the next steps.
3. Pull your boiled jars out of their bath and dry them. While they are still hot, fill them with your recipe! Leave about a half inch of empty space above the product.
4. Give the product a little swirl with a spoon or spatula to release any air bubbles.
5. Thoroughly wipe down the rims of the jars so that no food residue remains.
6. Place the lids and bands, screwing them snugly but not too tightly.
7. Place the jars into the rack in the canning pot. The jars should be fully submerged and covered by at least an inch of water. Put the lid on the pot.
8. Bring the pot to a boil and allow the jars to bathe in the bubbling water for at least ten minutes.
9. Remove the pot lid and allow the jars to rest in the hot water for another ten minutes.
10. Pull the jars out of the pot and place them on a towel or rack to cool. Do not open or adjust the lids; they’ll need to sit for about a day.
11. Once the jars have cooled after about 24 hours, check to see if they were sealed properly by unscrewing the bands and pressing down gently on the lids. If the lid is taut and doesn’t spring back up when you remove your finger, it has sealed correctly! If the lid does pop back up, the jar didn’t seal. In that case, you’ll want to place the jar in the fridge and eat the contents within a week or two.
Properly sealed jars can be placed in a closet and stored for up to a year! Remember, food safety should always be your Number One concern when preserving your harvests. Do your research to find safe recipes when using the hot water canning method, and always check for signs of botulism. If you see the jar lid bulging, if the jar is under pressure when you open it, or if the food smells or looks bad, it’s best to toss it.
Happy canning! Let us know if you come up with any delicious ways to preserve those bountiful harvests this season.