The New Guidelines for Canning

Preserving, or preparing foods to keep without spoiling, has been employed for centuries. One popular method is pickling with refrigeration: Fresh produce is covered with a mix of vinegar, herbs, and spices, then packaged and refrigerated. Another often-used method is canning, which hermetically seals food in a glass jar for pantry storage for up to a year. Though canning may seem daunting, it can be quite enjoyable, provided proper care is taken.

Canning is a fairly tried-and-true practice, but recently there's been big news in the canning world: Jarden Home Brands, the company that manufacturers Ball® Brand jars and lids, updated its guidelines for the sterilization process. While the old guidelines recommended dropping the lids in hot, simmering water before pulling them out and immediately sealing jars, Jarden now says it's not necessary to heat the lids in order to achieve a good seal. Instead, you can simply wash the lids and use them at room temperature.

The blog Living Homegrown got to the bottom of the situation, and it turns out the update is a result of Jarden testing the process and determining the extra step just wasn't necessary—not to mention that accidentally overheating the lids' rubber gaskets can cause the plastisol to thin out, resulting in a bad seal. While the USDA canning instructions have not changed, you might want to consider changing your process if you're going to be using Ball® Brand jars for canning this season, since this seemingly tiny change could potentially have implications for the safety and longevity of your canned goods.

Check out Theresa Loe's post on Living Homegrown for the full details on the update, and check out our primer for getting started with preserving your own foods below:

EQUIPMENT

There are only a few necessities for canning. The USDA recommends using tempered-glass jars free of cracks, nicks, or other defects that have a two-piece vacuum cap consisting of a flat, rubber-lined metal lid and a metal screw band. (Note: The flat metal lid is not reusable.) You will also need a boiling-water canner or a large pot that is at least 2 inches taller than the largest jar you plan on processing and is outfitted with a rack and lid. Use a jar lifter or tongs to safely lower and remove jars. Lastly, you will need a long, thin, nonmetallic skewer to insert into the length of the jar to remove trapped air bubbles. Home canning kits include everything you'll need.

INGREDIENTS

Quality counts! Using the freshest produce yields the freshest-tasting results. Always wash produce thoroughly to remove any microorganisms that may be present and that could contribute to spoilage. And always follow a recipe from a trusted source to the letter—these recipes have been tested to ensure that acid levels safely preserve the contents and that processing times are long enough to create a vacuum seal.

PROCESS

Your work area, produce, and all equipment must be meticulously clean and free of defects. Set up the boiling-water canner according to manufacturer's instructions. Any preserve that processes in a boiling-water canner for less than 10 minutes will require that jars be sterilized—submerge them in boiling water for 10 minutes and keep in hot water until ready to fill. Lids should not be sterilized but some say they must be hot: Submerge them in simmering water for 10 minutes (but feel free to skip this step if you're following the updated guidelines from Ball® Brand). Reduce the risk of bacterial growth by inserting the long skewer into filled jars to remove air bubbles and wiping each rim dry. Firmly secure lids and process all jars in the canner for the time specified. Test to see if jars have sealed properly by pressing on the center of the lid, which should be slightly depressed. Any jar that isn't sealed should be stored in the refrigerator and contents should be eaten in 2 to 3 days.