Over the last few decades, the art of canning produce has changed some, but the age group taking part has changed quite a bit.
Judy Fankhanel, who teaches family and consumer science at Detroit Lakes School, has also been teaching classes through the Extension Office in Wisconsin and now community education class in Detroit Lakes.
In the beginning, she said, it was people in their 50s and 60s. Now, it's everyone down to teenagers with an interest.
While canning used to be a cost-savings measure, "now it's preserving their stuff," she said. "You're getting quality (items) by doing it yourself."
Plus, for people with different health concerns, it's easier to can their own food and not have to worry about buying certain foods and reading labels at the grocery store.
Debbie Botzek-Linn, a food safety educator with the University of Minnesota Extension office, agrees that she has seen a change in ages, types of foods preserved and even gender of food preservationists.
"More men got involved in home food preservation in the last four or five years," she said. "I say salsa brought men back into the canning kitchen."
She said she's seen more people in their 20s and 30s getting interested -- and some who haven't canned in years are returning to it, either for themselves or because their daughters or daughters-in-law want to learn from them.
"They're coming back because they want to help teach them," she said. Fankhanel started canning with her mother when she was in middle school. When she got married and had four children, the family had a garden the size of a football field.
She made everything from jams and jellies to salsa and marinara sauce, and that's what her kids still look forward to when they come home now that they're grown.
And of course she's passed along her canning skills to her children.
Her daughter and her family brought 80 pounds of tomatoes home for a "canning lesson."
Fankhanel said she's had many people in their 50s and 60s take her classes because they haven't canned for years and have forgotten how. Now, the younger generation is getting interested in canning and drying foods.
"You can process food that is high quality and then put a personal touch to it," she said.
Five years or so ago, Botzek-Linn said she saw a definite influx in those starting to preserve foods because of the dip in the economy. It was a cost-saving effort.
"First of all, gardening increased. So, when gardening increased, it led to 'now what do we do with this?' Other factors are interest in local foods, interest in organic, interest in quality and knowing where your food is from," she said as contributing to the increased interest in food preservation.
Now that the economy has either continued as is or even picked up, there is still an interest in canning and freezing foods.
There is a science and art to canning foods, Fankhanel said. While you need to know the science behind what baking soda does, for example, it's the spices and seasonings that each person adds that makes it their own creation.
She said that if you have an old Ball Brothers canning cookbook, update it, because the acidity and such in produce has changed over the years, and therefore recipes need to be adjusted.
Botzek-Linn said she emphasizes the safety aspect through her extension classes. Several years ago, her main focus was helping vendors who wanted to sell their products at farmers markets and such.
"We emphasize learn how to do it properly, safely, the right methods, use reliable research-based resources, have someone who knows how to do it teach you," she said. "But make sure they are using the right methods," she added with a laugh.
She said that over the years there have been some changes to the methods and safety measures for preserving foods. Low acid foods, like vegetables and meats, need to be pressure canned. The water-bath process for pickles and jams and jellies has also changed, she said.
"Years prior, you just filled the jar, put the brine on, put the lid on and set it on the cupboard," she said. "Now there's usually a 5-10 minute water bath process on those."
Tomatoes need to have additional acid added to the jars, which just means adding lemon juice with the tomatoes.
"It's just to make sure our tomatoes are acid enough to safely (use the) water bath process," she said.
Not properly preserving food can result in deadly botulism -- a rare but serious illness caused by bacteria and most common in home-canned vegetables, cured pork and ham, smoked or raw fish, and honey or corn syrup, according to PubMed Health.
Improper canning techniques can also cause lesser problems, including a poor quality product and molding of the food.
While it can be an expensive investment to begin with, Fankhanel said she's known people to share equipment and have canning parties -- that shares the cost, cuts the work, and can be more fun than going it alone.
Botzek-Linn said she sees the biggest interest in canning salsa and pickled products.
Fruit -- "because it's so easy to freeze" -- sweet corn and tomatoes are the most popular items to freeze.
While her children have moved out and her garden has shrunk to a "postage stamp size," Fankhanel said she still enjoys growing her own produce -- or going to the farmers market for what she doesn't grow -- and canning some foods to enjoy all winter and spring.
"You just have to adjust things," she said of the smaller garden.
Botzek-Linn said family heritage has been a big reason for people preserving food, or coming back to it.
"I had one woman came and wanted to learn pickled okra and that's it, because that's what her grandma used to make," she said. "There's that flair to it, too."
Follow Pippi Mayfield on Twitter at @PippiMayfield.