YOU `CAN' DO IT TOO: AS HOME CANNING MAKES A COMEBACK, SAFETY ISSUES ARISE

Susan Mills gets questions year-round about canning everything from fish to green beans to homemade jams and jellies.

"June, July and August are our busiest seasons by far," she said. "We get 40-50 calls a day, asking questions from `How to?,' to `Can I do this?'"

Mills, a specialist in food nutrition at the University of Missouri Extension office in Jackson, answers the questions with a happy heart and a cheerful tone, hoping that the home-canners will follow her directions to the letter.

"You may think, `What's the big deal?'" Mills said. "The fact is, that people die every year from improperly processed, canned food.

"In other words, your green beans can be lethal if you don't preserve them properly," she said. "There are tons of people out there doing it the way their mothers used to can -- and those methods have been proven dangerous by modern standards."

Canning isn't so hard, it just takes attention to detail.

The process of canning is one of removing air from the jars through the application of pressure via a canner, creating a vacuum inside. The absence of fresh air keeps the food "fresh."

Storage in a cool, dry place adds to the longevity of the final product.

If too much or too little pressure is applied for too much or little time, the integrity of the finished product can be compromised.

The University of Missouri Extension office publishes a free canning information booklet, updated each year by the USDA. Mills turns to the booklet for answers more often than not.

"There hasn't been a question we couldn't answer yet," said Mills. "But tomorrow is a new day."

Teresa Meier works as a secretary at the extension office three days a week, but at home is a canning queen.

"I do mostly tomatoes, green beans, meat and tomato juice," said Meier. "As far as I'm concerned, canning is better than freezing. I run out of freezer space a lot quicker than I run out of shelf space."

Canning can be expensive, especially if the would-be canner doesn't have a garden.

"After you buy all the fruits or vegetables you need for a batch, that's already quite an investment," said Meier. "And that's not counting the time, effort and other resources like jars, lids and a canning pot."

If the tops of cans that have been sitting on the shelves are bulging or mold is visible, the entire jar should be discarded.

"That means something went wrong somewhere down the road," said Meier. "It's good when obvious evidence pops up. You can't see salmonella poisoning, but it is a very real threat to improperly canned food."

The threat of salmonella poisoning is one of the reasons the extension office suggests that canned food be used in less than a year's time.

"We get calls from people who say they have food that has been on the shelf for five, even 10 years, and claim that it is fine, but I wouldn't eat it," said Mills. "I wouldn't want to eat anything that is much more than two years old. You just don't know what could be incubating in there, or if it was properly canned five or 10 years ago."

When a can of food is opened, the extension recommends boiling the fruit or vegetable for at least 10 minutes before serving.

"That will kill just about anything," said Mills. "It's a safety precaution that is so simple."

The university extension office will, for a small fee, test the pressure gauges on people's canners. If the gauge is more than two pounds off, it is recommended that it be replaced.

Mills said that canning is coming back into style, especially with the middle-class crowd of first-time homeowners.

"Everyone thinks that by growing their own food, they'll save all kinds of money," said Mills. "But that first year that they do their canning will cost them in supplies.

"Canning allows people to have a creative outlet -- a way of harvesting and using it as a hobby," she said. "And people can also eat the food in the winter months or when it would otherwise be considered out-of-season, knowing where it came from and how it was packaged. People like that."

But the majority of the canning crowd comes from the older generation, where canning was a way of life.

"Young people just don't have time to do canning any longer," said Mills. "But a lot of older people will can fruits and vegetables and give them away to relatives, keeping the canning spirit alive, I suppose."

The number of people who canned fruits and vegetables in their homes began to decline in the 1980s, but is now on the rise again, Mills said.

"But if you were to compare the number of people today that can their own vegetables to the number 20 years ago, there would be a big difference," she said. "Maybe someday, home canning may become obsolete."

Stay clear of unsafe canning equipment and methods

-- Never process jars of food in conventional ovens, microwave ovens or dishwashers. These practices do not prevent spoilage.

-- Steam canners aren't recommended because safe processing times haven't been adequately researched. Using boiling-water canner processing times with steam canners may result in spoilage. So-called "canning powders" are useless as preservatives and do not replace the need for proper heat processing.

-- Jars with wire bails and glass caps make attractive storage containers for dry foods, but don't use them for canning. One-piece zinc, porcelain-lined caps are no longer recommended.

Keep your canned foods looking and tasting fresh

To make sure your canned foods keep the best possible color and flavor during processing and storage:

-- Use only high-quality foods at their proper maturity, free from diseases and bruises.

-- Use the hot-pack method, especially for acid foods to be processed in a boiling-water canner.

-- Prevent darkening of fruits by holding them in a Vitamin C solution.

-- Fill jars while food is still hot, and use the correct head space specified in recipes.

-- Tighten screw bands securely, but not as tightly as possible.

-- Process and cool jars.

-- Store the jars in a cool, dark place.

-- Can no more food than you will use in a year.