Tag Archives: Canning

But my jars sealed…

Often when people ask if their canned food is safe even though they know or have been told they processed them unsafely, they end by saying “the jars sealed”.  Or, they are finding really old home canned jars of food they forgot about, or found, when cleaning out a relative’s home. “They’re sealed so shouldn’t they be safe?” Here is short posting to say that a sealed jar is not a sign of food being processed safely!

A vacuum seal that forms on a canning jar after processing only means that there is a sealed_lidvacuum holding the lid on. To create a vacuum requires enough heat produced in the contents and the lid and then a cooling process that draws the vacuum.  The heat required to form a vacuum seal with today’s canning lids is much less than the heat needed to sterilize most foods.  Killing of spores of C. botulinum bacterial spores in low-acid foods, for example takes much more thorough and severe heating throughout the food mass than the heat needed to sufficiently warm the lid and headspace for vacuum to form after cooling.

Even killing of harmful bacteria like E. coli or others of concern in acid foods would take more heating of the jars of food than that needed to cause a vacuum seal to form during cooling. Enough heat has to get distributed throughout all parts of the mass of food in the jar to get to wherever the bacteria might be.

If a food was processed safely, a vacuum seal then needs to be maintained during storage of canned foods on the shelf to keep the food safe. The vacuum seal prevents food from being re-contaminated (and drying out). But a vacuum seal by itself is not a sign that the food inside was processed correctly to make the food safe.

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It’s Peak Apple Time

Fall weather brings the best fresh apples in bushels.  While we are in a season of peak applechutneysmallapple production in many states, you might consider preserving some specialties that will add variety to menus throughout the year.  Apples can be dried, made into applesauce or apple butter, or even made into a delicious apple pear jam. Those who treasure the crispness of fresh apples will not be impressed by soft canned or frozen apple slices, but they can be preserved by those methods, also.

Whether you are buying apples by visiting the nearby orchard, the grocery store or market, or even picking apples from your own backyard, choose the preservation method that is best for your apple variety. Varieties that are good for freezing include: Golden Delicious, Rome Beauty, Stayman, Jonathan and Granny Smith. Varieties that are good for making applesauce and apple butter include: Golden Delicious, Rome Beauty, Stayman, Jonathan, Gravenstein and McIntosh. Red Delicious apples are best eaten fresh. They do not freeze or cook well in most opinions.  There are so many newer varieties in the last few years, it will take some time to get this list updated, but it is a starting place for your choices.

When selecting your apples for preserving, choose apples that are free of defects, such as bruises, skin breaks and decayed spots. Little brown spots appearing solely on the skin of the apple, called “russeting,” does not affect quality of the tissue underneath. Beware and on the lookout for browning or broken skins that are evidence of actual spoilage such as rotting or mold.

If making applesauce, apple butter or dried slices with your apples, use them as soon as possible after harvest. If any apples must be stored, keep them in a cool, dark place. They should not be tightly covered or wrapped up; a perforated plastic or open paper bag, basket or wooden crate are good choices. If kept in the refrigerator, apples should be placed in the humidifier compartment or in a plastic bag with several holes punched in it (or in a zipper-type vegetable bag). This prevents loss of moisture and crispness. Apples should not be placed close to foods with strong odors since the odor may be picked up by the apples.

Here are some options to prepare for and choose from in preserving your apples:

Making and canning a flavorful applesauce:
http://www.uga.edu/nchfp/how/can_02/applesauce.html

Making and canning a tasty, robust apple butter:
http://www.uga.edu/nchfp/how/can_02/apple_butter.html

For those who want a no-sugar added apple butter:
(ours was developed  for sucralose as a sweetener but no sweetener is necessary)
http://nchfp.uga.edu/how/can_02/apple_butter_reduced.html

Drying apple slices or rings:
http://www.uga.edu/nchfp/publications/uga/uga_dry_fruit.pdf

Combining the best of fall fruits in tasty pear-apple jam:
http://www.uga.edu/nchfp/how/can_07/pear_apple_jam.html

Making old-fashioned, pretty crabapple jelly:
http://www.uga.edu/nchfp/how/can_07/crabapple_jelly.html

Canning a special, spicy gift-quality apple chutney: apple chutney
http://www.uga.edu/nchfp/how/can_06/apple_chutney.html

And if you like the option of a spicy pickled profile, also check out this apple relish:
http://nchfp.uga.edu/how/can_06/harvest_apple_relish.htm

And, for all those extra apple slices to save for pies and desserts later in the year, freezing:
http://www.uga.edu/nchfp/how/freeze/apple.html

For more information on canning and freezing methods, including packaging choices and headspace for freezer containers, see general sections on these topics available from the National Center for Home Food Preservation at the University of Georgia, https://nchfp.uga.edu.

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Canning Dry Beans: It Matters How They Go in the Jar

As a low-acid food, all beans require the use of a pressure canner for preservation by home canning, unless they are sufficiently pickled (acidified) to bring them out of the low-acid food category. But pressure canning isn’t a magic bullet if you don’t know the safe way to prepare food and carry out the right process for each food type and style. If you are new to pressure canning or could use a refresher of the basic how-to, then please read Using Pressure Canners before beginning. If this is your first time canning, then also read Principles of Home Canning from the USDA Complete Guide to Home Canning. 

The USDA recommended processes in the Complete Guide to Home Canning for home canning dried beans require a hydration step prior to filling jars:   https://nchfp.uga.edu/how/can_04/beans_peas_shelled.html

The options are to (1) place sorted (for stones or other contaminants) dried beans or peas in a large pot and cover with water. Soak the beans 12 to 18 hours in a cool place. Then drain off the soaking water and do not use it in canning the beans. The other option is, to more quickly hydrate the beans (2) cover the sorted and washed beans with boiling water in a saucepan. Boil them 2 minutes, remove them from the heat, soak them 1 hour and then drain. That cooking water is also not used in canning the beans.

The procedure then calls for covering drained beans hydrated by either method with fresh water and boil 30 minutes. The USDA canning process recommendation is for a hot pack prepared this way only: hot beans boiled 30 minutes then filled quickly into jars while still hot. (But of course being careful not to burn yourself, as with all canning steps.) Optional salt can be added to the beans in the jars if desired (½ teaspoon of salt per pint or 1 teaspoon per quart jar). The jars with cooked beans (and salt if added) then get filled with the hot cooking water, leaving 1-inch headspace. As with all jars packed this way, water should cover the food pieces for expected heat distribution during processing and best quality in storage of the canned beans.  See the link above for full instructions and the processing times and temperatures (pressures) for pints vs quarts, and for various altitudes.

According to inquiries I get, and what I read elsewhere on the Internet, it is popular practice to put dry beans in the jars, cover them with water and put them into the pressure canner that way. Unfortunately, I have never found or been shown research for home canning that has determined what the process time should be for dry beans filled into jars in this manner.  A safe process time is partially dependent on jar size and type of food, yes, but it is also partially dependent on the texture of the food, the temperature of the food and liquid, and the weight of the food filled into jars.  Dry beans sitting in water at the start of the process time will not heat up at the same rate as beans prepared as described in the research-based method described above and in the USDA materials. The final sterilization of the jar contents achieved by the end of the process will not be the same as when the process is applied to jars filled as described in the recommended methods.  People canning their dry beans by other methods, and especially by starting with dry beans in the jars, are taking a big risk on food spoilage and possibly botulism food poisoning.  Those doing this and getting away with it have just been lucky – so far.

I guess part of my message is do not expect me to endorse or support this method of filling jars for home canning of dry beans.  If you choose to do it, you are taking a chance by your own decision.

There are also different processes for different types of beans and dry bean recipes for home canning. For canning dry beans, there are research-based processes in the USDA database for Baked Beans, prepared as described in the process directions, and Dry Beans with Tomato or Molasses Sauce versions provided.

If you have fresh beans of the Lima variety, then follow these directions for Fresh, Shelled, Lima Beans. Follow these similar procedures, but slightly different directions for Snap and Italian Green and Wax Beans. As you’re deciding whether to prepare a hot pack or raw pack, remember that hot packs are often considered to produce the highest quality final product, and you can often fit more beans into one jar, even though raw packs do cut down on the prep time.

The home canning processes which we can recommend for these various bean products can be found at the National Center for Home Food Preservation website at this menu: https://nchfp.uga.edu/how/can4_vegetable.html .

Please be safe in your home canning choices. The research-based processes available may seem very limiting and traditional but there has been little public funding for researching new recommendations in a long time and there are few labs set up and staffed to do home canning research. You can flavor or combine your home canned vegetables with other ingredients after opening them, at the time of serving, rather than risk botulism or losing money from spoiled food from making up a process for your own recipes. This solution doesn’t address choosing an easier way to fill jars than has been tested such as with dry beans, but is something to consider for other food choices.

Even though this has been about dry beans, I hope you all are looking forward to another season of local, fresh vegetables coming in like I am!

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Learn Before Canning Vegetables

Another tragic story has been told about botulism poisoning resulting from improperly home-canned peas. Three women arrived at a New York hospital on morning last summer with acute nausea, dizziness, blurred vision, slurred speech, droopy eyelid, thick-feeling tongue, and shortness of breath. This was about 14 hours after they shared a homemade potato salad containing home-canned peas. (Of course, not the most common type of potato salad to many!) CDC released botulinum antitoxin that was administered to all patients about 12 hours after arrival at the hospital. All three patients survived, BUT, two developed respiratory failure requiring intubation and mechanical ventilation in the emergency room and the third was intubated that evening.  All three did require prolonged intensive care, with a range of 34-54 days, and rehabilitation.

Because a family freezer malfunctioned, one of the patients home-canned commercially frozen peas to “save them”. This was done 1-2 weeks before consumption. It turns out this person used directions for preserving a peach preserve in a boiling water canner, unaware that low-acid vegetables needed pressure canning to eliminate spores of C. botulinum. This is a good reminder that frozen vegetables may contain these spores as well as fresh ones. After processing, one of the jars did not seal so she refrigerated it. These are the peas consumed in the potato salad.

Yes, our USDA guidelines say that foods in jars not sealing after processing could be refrigerated and consumed within several days. HOWEVER, this is for jars correctly processed in the first place that did not pull a vacuum to seal the jar. Toxin was recovered from the jar and leftover food in the potato salad bowl. And that toxin matched that in stool specimens from two of the patients. Yes, it was those peas.

The closed jar of peas containing spores of C. botulinum held in the refrigerator for 1-2 weeks did indeed produce toxin. These spores like a low-acid, moist, oxygen-free environment. I wonder what the refrigerator temperature was, also.

dial=gauge pressure cannerPlease use recommended, science-based processing methods for home canned foods, especially low-acid ones. And if processing errors occur, discard the food or reprocess according to recommended guidelines within 24 hours. And, this is a reminder that even foods made with commercially processed ingredients can lead to serious consequences including death, if canned incorrectly.

See www.homefoodpreservation.net, the 2015 USDA Complete Guide to Home Canning (https://nchfp.uga.edu/publications/publications_usda.html) and So Easy to Preserve, 6th ed. (https://setp.uga.edu/).

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Reference:  Morbidity and Mortality Weekly Report, 68(1):251-252. March 15, 2019. Notes from the Field: Botulism Outbreak Associated with Home-Canned Peas — New York City, 2018.  https://www.cdc.gov/mmwr/volumes/68/wr/mm6810a5.htm