Abundant gardens may mean canning, freezing is in store
More consumers are gardening this year to save money on their grocery bills. If harvest is bountiful this summer, freezing and canning excess produce is an option, a University of Nebraska-Lincoln food safety specialist said.
However, certain guidelines need to be followed to assure that produce remains safe and of high quality, said Julie Albrecht, UNL food safety specialist in the Institute of Agriculture and Natural Resources.
Albrecht expects more people will be preserving food this summer. When it comes to preserving food, Albrecht said the easiest thing to try is freezing.
"If you have never canned before, I really recommend freezing if you have a stand alone freezer," Albrecht said. "It is safer."
The stand alone freezer is key. A freezer that is part of a refrigerator really isn't meant for long-term storage, she said.
"You really need to have a freezer that reaches zero degrees or less. A freezer with a refrigerator isn't going to get that cold," she said. "These freezers really can only keep food fresh for about three months or less. And if the freezer is inside the fridge up to 10 days."
Freezing also is less expensive because you don't have to purchase a pressure cooker. When canning vegetables, the only safe way to preserve them is with a pressure canner. This is the only way to destroy the deadly spores of the bacterium Clostridium botulinum. This is done by processing for the correct time at 10 pounds of pressure which forces water to boil at 240 degrees at sea level.
More detailed information about canning, including altitude adjustments and processing times, is available by consulting UNL Extension Circular 434, "Let's Preserve: Canning Basics," available at local UNL Extension offices or online at http://www.ianrpubs.unl.edu/sendIt/ec434.pdf.
"Using a hot water bath, the oven or anything else for canning vegetables is not safe," she said.
It is safe to can fruit, jams, jellies and pickles using a hot water bath because of the higher acid content of fruit and the pickled product.
Tomatoes can be canned in a hot water bath because of their acid content. However, more and more newer tomato varieties have lower acid content, so it is now recommended to add some lemon juice or citric acid to the jars. It only requires a small amount, about 1 tablespoon per pint, she said.
"Acid inhibits the spores from Clostridium botulinum growing out," she said.
Caution also should be given when canning salsas.
"Be sure to follow the recipe," Albrecht said. "Don't throw in more peppers because it will reduce the acid content. The safety of canning in a hot water bath really depends on the acid content. Use tested recipes as they are safe to process in a boiling water bath. If you don't follow the recipe, be sure to refrigerate the product."
When freezing vegetables, they first need to be blanched, Albrecht said.
This is because enzymes in the vegetables continue to break down even when frozen. If the vegetables are not blanched, corn will begin to taste like the cob and broccoli will smell awful, for example.
"Blanching inactivates those enzymes and also allows you to get more vegetables in a container," she said. When freezing vegetables, be sure to use freezer storage bags or containers that are freezer safe.
When blanching, bring water to a boil and then drop the vegetables in. Cook times for some vegetables include: green beans, 3 minutes; broccoli, 3 minutes; corn on the cob, 11 minutes; corn cut off the cob, 3 minutes; peas, 1.5 minutes and beets, cook until done. After cooking, plunge into ice cold water, drain, package and place containers one layer deep in the freezer to quickly freeze.
Albrecht said freezing also gives vegetables a "less cooked" taste and they are not as mushy.
Additional publications about food preservation are available at the UNL Extension publications website at http://extension.unl.edu/publications. Click on "Food & Nutrition", under "Browse Publications" then scroll down to "Preservation".
Additional Nebraska Extension resources to meet today's challenges are available at the UNL Managing Tough Times website at http://www.toughtimes.unl.edu.