Water Bath Canning
Boiling water bath canning is a method of preservation used for high acid foods like preserves and pickles. For foods to be safely water bath canned, they must have a pH level below 4.6. At this level of acidity, botulism toxin cannot grow; the boiling water kills other bacteria that might be present, sterilizing the jars in the process.
In general, it is best to follow tested recipes when canning, playing around only with ingredients that will not affect acidity (like switching out ingredients with the same pH level) or that will increase acidity (like adding lemon/lime juice or vinegar). Luckily, most fruits are fairly high acid and can be safely canned with a fair amount of flexibility in preparation. The website Pick Your Own has an excellent chart listing pH levels of most foods that people may want to can at home. To give yourself some leeway with varying acidity levels, most experts recommend adding acid if the product being canned has acidity level above 4.0
Canning pot: 10 quarts is ideal if you will only be canning 8 oz. jelly jars — larger if you plan on canning pints.
Canning rack: Many people use a metal rack. I prefer a silicone trivet, which was recommended by Marisa McClellan of Food in Jars.
Stockpot: This is where you’ll actually make the preserves. I typically use a 6 quart stockpot. You won’t generally fill it up to the top, but jams bubble up a lot as they cook and you do not want overflow.
Jar lifter: You’ll need something to get those jars in and out of the water bath without scorching yourself. They’re not expensive, but super important. This is pretty standard.
Funnel: The best way to get your jam into jars without spilling it everywhere. You’ll want something fairly wide, like this one.
Until recently, lid lifter would have been included on this list. The most recent directions, at least with two part lids, do not require the lids to be heated up before use anymore, making lid lifters unnecessary.
Two piece vs. one piece closures
Standard canning procedure calls for the use of two piece lids — caps with separate rings where the rings are reusable, but the caps are not. This past summer, after reading Marisa McClellan’s post on one-piece lids, I tried them out for myself and found that I really liked them. The process is fairly similar to using two-piece lids, the primary difference being that jars processed with one-piece lids should be left in the hot water for five minutes after processing is complete. They also generally take a bit longer to seal, but I’ve never had any failures and so far every jar I’ve processed with a one-piece lid has sealed within half an hour of being removed from the water bath.
Along with smooth-sided jars, one-piece lids are especially appealing when canning preserves that will be gifted to friends and family.
When I first learned water bath canning, a number of websites and books were indispensable to me. This is by no means an exhaustive list, but it’s a great place to start.
Food in Jars: Written by Marisa McClellan, Food in Jars includes recipes, giveaways, and excellent information for beginners to water bath canning.
Fillmore Container: Jardin brands (Ball and Kerr labels) has a near monopoly on canning jars in the United States. They’re great jars, but they are usually textured, making creative labeling difficult. Fillmore carries smooth sided canning jars of all sizes at reasonable prices. They also carry one piece lids for low and high heat canning.
Pick Your Own: This may not be the prettiest website, but it is a wealth of information, not just for canning (both types), but also as a resource for finding where to pick fresh fruit and vegetables locally.
Saving the Season: This site is updated less frequently than others, but the recipes are creative and interesting — definitely worth checking out.
Canning for a New Generation: A clever book aimed at those of us who may not have grown up with canning as a family tradition (hello!), the chapters are organized by season, giving you the opportunity to can produce when it’s at its freshest.
Food in Jars: An excellent book with recipes that haven’t all appeared on Marisa’s site.
Preserving by the Pint: Also by Marisa McClellan, this book focuses on small and micro batch canning, which is perfect for those of us with small kitchens and little storage space.