HOME & AG: Most vegetables need to be pressure canned
Mar. 22—Jarring revelations can help canners and jarrers can diseases while canning cans or jarring jars.
According to a fact sheet from Oklahoma State University Extension, spring vegetables planted in mid-February or early March will soon be ready for harvesting, including asparagus, beets, broccoli and cabbage.
Christi Evans, family and consumer sciences educator at the Cleveland County OSU Extension Office, said backyard garden enthusiasts can preserve the life of their produce by jarring fruit and vegetables, but she warned against doing it without a plan.
"Home canning can be fun and affordable, but it can also bring food safety risks if not done correctly," Evans said. "Botulism poisoning is a rare but serious foodborne illness caused by a toxin that attacks the body's nervous system. You cannot see, smell, or taste the toxin, but ingesting just a small amount can cause difficulty breathing, muscle paralysis, and even death."
She said to prevent botulism, it is important to follow the current recommended research-based guidelines, which can be found in the U.S. Department of Agriculture's Complete Guide to Home Canning, the National Center for Home Food Preservation website, or by connecting with OSU Extension.
Evans said it is important for home canners to update themselves on current best practices, even if they are using old recipes.
"Families may have recipes that were passed down, or they find recipes in older cookbooks, but these recipes and guides might not have the correct processing instructions," she said. "Foods prepared from these older recipes can pose a serious health risk to families, so it's important to use current reliable sources."
Canned foods don't need to be limited to fruits and vegetables, but it is important to know how to process each kind of individual food. Popular non-vegetable canned items include meat, poultry and seafood such as tuna.
Evans said there are two methods of canning: warm bath canning and pressure canning. Warm bath canning is great for foods that are high in acid, such as jam, jellies and picked foods.
"Low-acid foods are those with a pH greater than 4.6, including milk, meats, and vegetables," Evans said. "These foods need to be processed in a pressure canner. Do not use a boiling water canner for low-acid foods, and do not use an electric, multi-cooker appliance, even if it has a 'canning' option.
She said botulinum spores are hard to destroy at boiling-water temperatures, which is why pressure canning is the only recommended method for pressure cooking on low acid foods.
The USDA recommends selecting a canner large enough to hold at least four-quart jars standing upright on the rack, with the lid in place.
"Smaller pressure cookers are not recommended because they won't be able to deliver the appropriate heat that is required during the pressurizing and cooling stages of the canning process," Evans said.
She said it is important to check the condition of the canner before each use and make sure the rubber gasket is clean, strong, and flexible.
"It should not be brittle, sticky, or cracked," Evans said. "Dial gauges should also be inspected each year."
Those who need help inspecting their canner can visit the Cleveland County Extension office where an expert will test it for free.
It is also important to check for altitude when canning. Norman sits at an altitude of 1,171 feet, which means canners may want to add a little time to their canning. For warm bath canning, she recommends adding five minutes, and for pressure canning, she recommends following the instructions on the canner or recipe.
"If you live at an altitude of 1,000 feet or more, be aware of necessary adjustments. Water boils at 212 degrees at sea level, but boils at lower temperatures as altitude increases. The processing time or canner pressure may need to be adjusted to compensate for the lower boiling temperature."
She said if food has signs of leaking, bulging, swollen containers, discoloration, and unusual smells, users should throw it out.
