Published on 07/02/09

Preserve your summer bounty

By April Sorrow
University of Georgia

More and more, people are planting gardens and preserving its bounty. For some, the draw is self-sufficiency and quality control.

“I have an organic garden, and I want to keep my organic produce,” said Ken Davis. “I know I could buy organic at the store, but I know exactly what I used to grow and can my food.”

Some people can food to preserve family traditions.

“Growing up, my mom always had a jar of something around the kitchen,” said Stephen Crae. “I want to keep up what she started.”

Crae and Davis recently attended class, offered by University of Georgia Cooperative Extension in Oconee County, on the proper way to can food to preserve it.

Canning fresh food isn’t easy. You can’t just put it in a jar and stick the lid on. And it isn’t fast. It takes several hours to can foods safely. It’s a scientific process that requires following instructions, said Denise Everson, the UGA Extension agent in Oconee County who taught the class.

“Food preservation does not allow for personal variations,” she said. “Creativity happens after you open the jar.”

You can’t leave ingredients out, add extras or double recipes. Recipes must be followed exactly, one batch at a time.

Process and cooking times are exact. Use recipes tested and approved by the United States Department of Agriculture or other food preservation specialists such as with Cooperative Extension, she said. Recipes tested and approved by the University of Georgia are available in the book, So Easy to Preserve or online at the National Center for Home Food Preservation Web site.


Canned foods need to be processed or cooked to a temperature high enough to destroy dangerous bacteria like Clostridium botulinum. Botulism is a potentially deadly illness caused by consuming the nerve toxin produced by bacteria found in dirt. According to Everson, nearly 80 percent of botulism cases occur from food preserved at home.

Numbness in fingers and toes, upset stomach, blurred vision and difficultly speaking, swallowing and breathing are signs of botulism that usually occur within 12 hours to 72 hours of eating tainted food. Once it starts, the nerve damage is permanent.

Processing jars also stops enzymes that can cause changes in color, flavor and texture.

There are two methods for processing jars: in a boiling water bath or pressure canner.

“The food you choose determines which method you use,” Everson said.

High-acid foods like fruits, pickles and tested salsas can be processed in a boiling water bath. Boiling water should completely cover the jars and sit at least one inch on top. Add jars when water is simmering, and start timing once the water boils.

“Table salt can make foods cloudy,” Everson said. “Acid levels are important in canning, so don’t use homemade vinegar or fresh lemons in canning recipes.”

Most vegetables, soups and meats are low-acid foods that need to be processed in a pressure canner. Start timing a pressure canning process once the correct pressure is reached. Dial gauges on pressure canners must be accurate and operated correctly to prevent injury or illness. Dial gauges should be tested each year. Many local UGA Extension agents can do this.

Canning 1-2-3

Use mason-style canning jars, lids and bands. Canning jars and rust-free bands can be used for several years. Lids, however, only create one safe seal and must be tossed once used.

To can properly, follow these steps:

• Prepare food as directed in recipe.

• If required, sterilize canning jars in a hot water bath.

• Fill hot jars with hot food. Leave correct amount of headspace listed in recipe.

• Remove air bubbles in jars using a plastic knife. Readjust the liquid and headspace if needed.

• Use clean, damp paper towels to clean jar rims before adding lids.

• Center lid over the jar. Screw bands down just enough to close finger-tip tight. (Do not overtighten.)

• Process in a boiling water bath or pressure canner for the required time listed for each food.

• When the process time is over in a boiling water canner, turn off the heat, carefully remove the canner lid, and let the jars sit for 5 minutes before taking them out. At the end of the process in a pressure canner, turn off the heat, let the canner cool naturally to 0 pounds of pressure. Remove the weight, let the canner cool another 10 minutes, then remove the lid carefully.

• Remove jars by lifting them straight up and placing them on a towel. Don’t move the jars for 24 hours.

• After they cool and seal, remove bands and wash jars with soapy water to remove any food residue.

• Store in a cool, dry, dark place.

• Enjoy canned foods within a year for best quality.

April R. Sorrow is a science writer with the University of Georgia Public Affairs Office.