Feature Articles: Food, Fitness and Cooking and Produce
Summer garden produce brings bounty of food preservation questions, concerns
When backyard gardens are overflowing with cucumbers, Grandma’s
home-canned pickles are not far behind. Before you take the first
bite of that crisp, tangy pickled cucumber, it might be wise to ask,
“Is her recipe safe?”
No offense to Grandma, but it’s probably not safe. Many of the
old family favorites use methods that have been deemed unsafe, said
Sarah Janicek, who answers food safety questions for University
of Missouri Extension’s nutrition education programs.
“People are still using really old recipes that are not reliable
or safe,” Janicek said. For Janicek and other extension nutrition
specialists, home canning questions are as much of a summer tradition
as Grandma’s pickles. Answers to those questions focus first and
foremost on ensuring that home canners know the current recommendations
to prevent the possibility of food-borne illnesses and spoilage.
Common mistakes include failing to heat pickles in a boiling-water
bath, and under-processing tomatoes and other items produced using
recipes based on trial and error rather than good food science.
Though the U.S. Department of Agriculture — the definitive source
on home food preservation — completely revamped canning recommendations
in 1989, old methods still persist.
“Sometimes they (home canners) don’t realize the risk they take
because up to this point they’ve managed to escape the most serious
consequences, or have not understood why jars come unsealed or spoiled
on the shelf,” said Cynthia Fauser, an MU extension nutrition specialist
in St. Louis.
For years “cold packing” — treating vegetable-packed jars in
a hot-water bath — was the favored method for green beans and tomatoes,
vegetables still popular among home canners. The technique was based
on pre-World War II science when microbiology was still in its infancy,
Food scientists now know that water-bath canning is not safe for low-acid foods, which includes vegetables, meats and vegetable-meat combinations, she said.
“CI Botulinum goes active when it’s canned,” Fauser said. “It
particularly likes low-acid, air-free environments, as in canning
jars with low-acid vegetables. It’s undetected by taste or smell,
but one taste can produce potentially deadly stroke-like symptoms,”
Janicek said, “Low-acid foods need to be pressure canned to kill
the botulism spores.”
Tomatoes are borderline acidic, so safeguards include added lemon
juice and increased processing times for many tomato products, Fauser
Tested recipes use processing times based on the specific recipe’s
pH, the size of the jar, thickness of the product and even altitude.
“That’s why home canners need to stick to tested recipes and follow
procedures precisely,” Fauser said.
“Just because the recipe has been published in a book doesn’t
mean it’s been tested. There’s no requirement for recipes to be
safety tested,” Fauser said.
Fauser and Janicek advise getting the latest processing recommendations
from the National Center for
Home Food Preservation, the home of USDA’s and Extension’s research
for home canning.
They recommend using only tested recipes from current MU Extension
publications, the “USDA Complete Guide to Home Canning,” or the
“Ball Blue Book.”
“I only recommend recipes from these three sources because they
are based on the recommendations from the National Center for Home
Food Preservation,” Fauser said.
Fauser added: “The bottom line is that you have to take the safety
into your own hands when you want to be a food processor.”
Missouri residents with questions about home canning can
contact the MU Extension’s Show-Me Nutrition line at
Residents can also call their county Extension office and ask for
the nutrition specialist.
MU Extension Quality for Keeps food preservation publications
provide additional information. They may be viewed or ordered online
or purchased at local Extension offices.
Sources: Sarah Janicek & Cynthia Fauser, former Nutrition and Health Education Specialists, University of Missouri Extension
Last update: Monday, July 28, 2014