Are you canning food properly? Here’s what the experts say
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IDAHO FALLS — With all that has happened this year, many of us are spending more time inside. One activity that has grown in popularity is home canning and preserving.
While this is a great way to prepare and store food for long periods of time, doing it wrong can cause many safety issues – some of which are deadly.
Food poisoning and microorganism-related illnesses, including botulism, can thrive in non-oxygen environments. They can be tasteless and odorless and may not be found until symptoms like lock-jaw set in.
EastIdahoNews.com spoke with Leslee Blanch, a Registered Dietitian and Family Consumer Science Associate Extension Educator with the University of Idaho, for some tips and tricks for those trying to can at home.
High Acid Foods
High acid foods include things like fruits, tomatoes, pickles and jams/jellies.
These foods can be canned with a boiling water bath method. However, since Idaho is at a high altitude, Blanch says that you need to add 10 minutes of boiling time to any recipe that does not have an elevation guide.
Important piece of advice: be sure to follow evidence-based research recipes.
“I know in this area, people have canned for years and years and they tend to use grandma’s and great-grandma’s recipes, but research and food safety is always up and coming and (has) new information,” Blanch says.
Her recommendations to find research-based recipies include:
- USDA Home Guide to Canning
- Ball Blue Book Guide to Preserving (Can be purchased on Amazon)
- So Easy to Preserve (Book can be ordered from their website)
Once you find a recipe from reliable sources, make sure to follow it exactly.
Low Acid Foods
Low acid foods include things like vegetables, meats and seafoods. Any canning substance that is a mix of high acid and low acid foods should be canned as is if it was a low acid food.
They must be canned with a pressure canner – not to be confused with a pressure cooker, according to Blanch.
“(Pressure cookers) are great for cooking your meals fast, but the problem is that it doesn’t get up to the pounds of pressure that we need at this altitude,” she explained. “We need 13 pounds of pressure at this altitude.”
These foods have a higher risk of botulism, especially root vegetables, because botulism bacteria can be found in soil. High acid foods can also be canned in a pressure canner, but don’t have to be.
In order to be sure your pressure canner is safely preserving food, Blanch recommends getting the pressure gauge and the seal on the lid checked before each spring and fall. They can be taken to any extension office in the county for this check, which costs $2.
When canning anything, cool according to the direction. Do not rapidly cool down cans. You want to make sure there is a slight concave in the lid after cooling is done in order to know a proper seal is made.
Most canners know the three parts: the jar, the flat lid that sits on top, and the ring that screws around the lid. Once the lid is concave and sealed in, Blanch recommends taking off the ring and wiping off anything that may have oozed out during processing, and then storing the jars without the ring. This way, if you ever notice more ooze coming out from a jar, you know the seal has been broken and can discard that jar.
Rings and jars are reusable, but always get fresh lids. Currently, there is a shortage of lids for canning, but reusing lids can result in jars that are sealed for a short time, but then the seal breaks.
Always remember to rotate stock, putting your most recently canned items in the back, and bringing the oldest items to the front. Properly label each jar with the date they were canned, and know when to throw out food that is too old. Five years is generally a good guideline.
If those at home have more questions about canning and preserving food, or any other FCS related activity, they can call the Bonneville County Extension Service at (208) 529-1390. There are many staffers that know a lot about canning, and Blanch herself can also answer question on wellness, nutrition and fitness while at home.