I don’t know how the conversation got started, but I was in my precious metals store, and I was speaking with a customer and an employee about canning. Go figure.
Neither of them had a clue about canning. What it is for, how you do it, and why the top of the lid “pings”. I’ve been home canning for so long, I figured everyone knew how it worked.
Here’s a quick overview of the process. For more information, please click the Member link above, go to the Independence Library section, and download the free Principles Of Home Canning put out by the USDA.
When we first started prepping back in the late 1990’s, I had visions of stockpiling food for an entire year with nothing but some mason jars and a pot of boiling water. Little did I know the adventures that lay ahead. If you’re about to embark on a home canning project, let me provide some hard-won guidance. There’s a lot of misinformation out there about canning and what can and can’t be canned. Let’s explore the topics a bit.
Two Types of Canning
There are two types of canning possible – the boiling water bath method and pressure canning. They’re not the same, and they’re not interchangeable. Some foods can be canned in a boiling water bath, but most of your garden’s bounty will need to be preserved using a pressure canner.
The boiling water method has been used for centuries – long before pressure canning was a possibility. However, don’t let that make you think it’s safe for all food types.
Boiling water in a lidded pot cannot reach a temperature high enough to kill botulism spores. Plus, foods that lack sufficient acidy can be a perfect environment for the spores to release their toxin. It’s a rare but deadly possibility.
What can be canned using the boiling water method? Pretty much all fruits can be canned this way, as can jams, jellies and other fruit-based products. Vegetables and animal protein (meat, fish, poultry) cannot, as they don’t contain enough acid to prevent botulism from flourishing.
Safe for Boiling Water Bath
- Fruit puree
Requires Pressure Canning
- Anything you home can that has meat, fish or poultry included in the jar
First Things First
The VERY first thing you want to do is to get a proven recipe from a trusted source. A home canning friend, a trusted Internet source, or one of the many local, state and federal agencies that have an interest in food safety.
Seriously, don’t just throw a bunch of food in a jar, and hope for the best.
In addition to a large stockpot or a pressure canner, you’ll need some additional equipment. Both methods require:
- Mason jars
- New lids and bands
- A funnel for adding food to the jars
- A pair of jar tongs/jar lifter
- A rack or trivet to place in the pot or pressure canner and keep the jar bottoms from direct contact
- Space to cool and store your canned food
Whether you’re using the boiling water method or you’re pressure canning, you’ll need to follow the pre-canning steps below.
- Make sure you start with new lids (always – don’t reuse lids. Bands can be cleaned and reused forever)
- Sterilize your bands, lids and jars in simmering water for about 10 minutes before beginning
- Heating your jars beforehand will also help prevent cracking when adding hot foods
- Blanch your vegetables just prior to canning
- Prepare your jelly/preserves/jam just prior to canning
Water Bath Canning
In water bath canning, all you need is a large stockpot, some mason jars, and new lids and bands. Fill your mason jars to the correct level (per the instructions in your recipe) with your fruit, jelly, jam or other appropriate food.
Next, wipe the rim of the jar, put the lid on and tighten the band finger tight (don’t over tighten). Place the jars into the boiling water (make sure the water covers the lids by about an inch or two), and let them process the proper amount of time.
Processing time is very important, and it varies from one type of food to another. As noted earlier, always use a verified safe canning recipe for the appropriate processing time.
Once processing is over, remove the jars from the water and allow them to cool on the counter. The lids should self-seal (ping!). Any that do not seal on their own should be reprocessed or eaten/refrigerated.
Pressure canning is similar, but is different from the boiling water bath method in some very important ways. It’s used for most vegetables AND ALL ANIMAL PROTEIN, and should be used for tomatoes as well (there’s a lot of contradictory information out there about canning tomatoes – be safe and use a pressure canner).
You’ll need a high quality pressure canner with a locking lid and a pressure regulator. You’ll find weight-based systems and gauge-based systems. Gauges are supposedly easier to use and more accurate. I personally use a weighted gauge canner, and love it.
Pressure canning is able to reach the temperatures necessary to kill off botulism and provide safely preserved foods. It’s ideal for low-acid foods like green beans, corn, peppers and the like.
You place approximately 1 or 2 inches of water at the bottom of the pressure canner (the manufacturer will tell you how much water to add) , prepare the jars exactly as you did with the water bath method, lock down the lid, turn on the heat and allow steam to vent for approximately 10 minutes, set your weight/gauge to the proper setting, and set your timer for the proper amount of time depending on what you’re canning, the size of your jars and your altitude.
This is important: When your time is up, DO NOT open up your pressure cooker. Aside from risking a nasty steam burn, you will likely introduce cool air too quickly, and you risk breaking your jars. Let the pressure and temperature slowly subside (per the manufacturers instructions), THEN open the lid (away from your face), remove the jars and allow them to them to cool.
Often times, the contents of you jars are still boiling when you remove them!
Time and Pressure
For Water Bath canning, high altitude canning requires additional processing time, which varies. In general, you add 5 minutes up to 3,000 feet above sea level, 10 minutes up to 6,000 feet and 15 minutes if you live higher than 6,000 feet above sea level.
For Pressure Canning, you have to add additional pressure pounds to ensure the internal temperature of your food reaches the proper levels necessary to kill the spores and microbes (remember, water boils at lower temperatures at higher elevations – that’s why more pressure pounds need to be added.)
Ball has an excellent altitude adjustment chart (click here – PDF).
Home canning can be an excellent way to preserve the food you’ve grown at home, providing you with healthy, organic fruits and vegetables throughout the entire year. It’s also a great way to take advantage of bulk sales at the store. Take advantage of the bounty, regardless of the source!