Canning: Modern practices matter more than experience

RUSSELLVILLE Canning season is underway with pressure canners whistling on stovetops and fresh vegetables filling jars across kitchen counters.

Whether someone is a first-timer or has been canning for decades, food safety experts say up-todate practices matter more than experience.

“There’s a lot of people that get sick from their home-canned green beans,” said Susan Hill, a regional Extension agent with the Alabama Cooperative Extension System’s Food Safety and Quality team. “Or worse, you have the potential of growing botulism.”

Botulism is a rare but serious illness caused by a toxin produced by Clostridium botulinum

bacteria. According to the Centers for Disease Control and Prevention, the toxin attacks the body’s nerves and can cause difficulty breathing, muscle paralysis and death. It is most often linked to improperly processed home-canned foods.

Hill said low-acid foods like green beans, corn, vegetable soup and other garden vegetables must be pressure canned, not water bathed, because of their risk for botulism. A pressure canner reaches 240 degrees, the temperature necessary to kill harmful bacteria. In contrast, a water bath canner boils at 212 degrees, which is only safe for high-acid foods like fruits, jams, jellies and pickled items.

“Even the hottest pepper, if it’s not pickled, has to be pressure canned,” Hill said. “I get a lot of calls from people saying, ‘Well, I boiled my green beans for two or three hours.’ You can’t do that. It’s not safe.”

To help determine which method is appropriate, Hill recommends using tested recipes from reputable sources like the National Center for Home Food Preservation, a partnership between the USDA and the University of Georgia. Many Extension offices, including Alabama’s, also share vetted guidance.

One of the most important rules? Never rely on memory.

“Every recipe is going to be different,” Hill said. “Do not memorize your processing times for anything.”

That advice holds true for tomatoes too, which Hill said are no longer acidic enough on their own to be safely canned without added bottled lemon juice. Fresh lemons are too inconsistent in acidity.

Ida Elliott of Tharptown, a longtime home canner, emphasized the same point.

“Tomatoes have changed over the years,” she said. “People think they’re still acidic, but they’re not like they used to be. That’s why the lemon juice matters.”

Elliott also noted another common mistake: Reusing jars that aren’t made for canning.

“You see those sauce jars that look like Mason jars. They even have measurements on the side. But they’re not made to seal properly. You can’t trust them.”

Canning lids should only be used once. Bands can be reused, but only if they are free of rust. Jars should be Ball, Kerr, Mason or Golden Harvest brands, cleaned and inspected for cracks before each use.

Hill offered detailed instructions for safe canning practices: 1) Wash jars in hot soapy water or run them through a sterilizing dishwasher cycle with no other dishes. Keep them warm before filling to avoid thermal shock.

2) Place hot food into warm jars, top with warmed (but not boiled) lids, and secure the rings “fingertip tight.” Overtightening can cause buckling or breakage.

After processing, Hill said, jars should be placed on a towel or mat on the counter and left undisturbed for 12 to 24 hours. Only after that should the seal be tested.

“If you press it too soon, it might fake seal. That’s dangerous.”

Even correctly canned food has a shelf life. Hill recommends using canned goods within two years for both quality and safety.

And don’t try to save time by doubling a jelly recipe.

“It won’t gel,” she said. “And don’t switch liquid and powdered pectin. They’re not interchangeable.”

Hill said she often receives questions about freezing food and then canning it later, but she advises against it.

“You want to use fresh produce and can it as quickly as possible after harvesting, ideally within two hours,” she said For Hill, some of her favorite foods to can are apple butter and vegetable soup. She also carries fond memories of learning to can from her grandparents.

“I’d hide behind my papa’s chair to watch,” she said with a laugh. “My grandmother didn’t want us underfoot, but I learned so much.”

While home canning can connect families with old traditions, food safety experts stress that newer methods and recipes reflect updated research. Past generations may have made foods one way, but that doesn’t mean it’s still safe today.