The Proven Methods
The only two methods of canning that successfully preserve food and are recommended by the USDA—as well as every other authority on food safety, from major universities to non-profit organizations—are the boiling water method (using a water bath canner) and the pressure cooker method. This means that all other types of canners and methods of canning, which include solar, microwave, steam, oven, and even canning in the dishwasher, are unacceptable and should be avoided.
When placed in a water bath canner or a pressure cooker canner, the canning jar is exposed to extremely high temperatures that prevent the food from spoiling and kill microorganisms that cause food poisoning. This heating process also drives air from the jar, creating a vacuum seal as the food cools.
According to the National Center for Home Food Preservation, not all foods can be canned the same way. Naturally acidic foods, like most fruits, can be processed using the boiling water method. Foods that contain low or no acid must be processed in much higher temperatures, which can be achieved in a pressure cooker canner. Botulism-producing bacteria are more likely to be present in low or no acid foods, and produce spores that can survive in boiling water, but are destroyed at 240º F or higher. Or you can alter the acidity of your food by adding vinegar, lemon juice, or any other type of citric acid.
Another big question for canners is whether the food can be packed in raw. Most fruits can be packed into the canning jars raw, with the exception of apples, pears, melons, and rhubarb, which must be packed into the jars hot. All vegetables must be hot prior to packing, though tomatoes are the one exception (but then again, tomatoes aren’t really vegetables, are they?)
The Necessities
So, now that you are armed with a little bit of history and background on the approved methods of canning, where to begin?
In addition to buying a much needed “how to” guide, like the Complete Guide to Home Canning and Preserving, a novice canner will need to buy canning equipment. A quick search on Amazon.com shows that a full water bath canning kit (water bath canner, jars, lids, rack, lifter, wand, funnel, and instruction book) can cost under $50.00. A pressure cooker canner alone (no jars, lids, or rack) runs about $100. Canning jars, like the Ball Mason Jar, can be reused several times and cost approximately $10 for a dozen sixteen-ounce jars. You can also buy reusable rubber lined jar lids, which cost approximately $5 for twenty lids.
And if you’re like me, go to your local farmers market and buy that bushel of pears, eat half of it before the week is through, and can the rest … because you can!
