Having a jar on the shelf that loses its seal happens to everyone once in a while. If it happens frequently, there is a problem.
What are the most common reasons?
Generally some experts say, your recipe was bad or your processing method was bad. A “bad” processing method could involve using a water bath when you should have pressure canned, or using an unsafe canning method, such as Open Kettle Canning or Oven Canning.
Jessica Piper, Ball spokesperson, says the number one reason is consumer error. One error is not using a proven, tested recipe:
The number one reason why lids come unsealed, based on the calls and everything that we get into our consumer affairs department, is when someone is using a personalized recipe, something that is your own, it’s not been tested, the problem with doing a homemade recipe is you don’t know the acidity, or the pH in general of that food going into your jar, .. at home you don’t have the tools to know, and even if you do have any kind of tools to figure out what the combined acidity of your recipe is, the next factor is the density, so when you’re processing you’re actually, um, the USDA has done thorough testing to find out what kind of heat penetration is needed to the coldest spot in your canner to kill the bacteria that is present and so if that doesn’t happen that bacteria can grow on like I said a smorgasboard in your beautiful canned goods jars, so one of the things, always follow a USDA tested and approved recipe, you can always add dry ingredients, like dry red pepper flakes, or maybe cinnamon to apple sauce, or maybe something else to add some flavour, but always use dry, using fresh changes the pH, so number 1 typically has to do with the recipe itself and going on further from the recipe, the actual processing method,” [1] Jessica Piper. Video: Canning Lids 101. 25:34 . Accessed March 2015.
She goes on to say that another error is water bath canning foods that should have been pressure-canned:
We still get quite a few folks call in who are water bath canning low-acid foods. The USDA deemed that unsafe decades ago .. so if you are water bathing, you are not necessarily killing the bacteria.. the bacteria that can grow in low acid foods such as vegetables, meat, stews, they require a temperature of 240 degrees F (115 C) , you will never get to 240 degrees F (115 C) in a water bath, you will max out at 212 (100 C), which is fine for high acid foods, not the case with low acid, it doesn’t matter how long you cook it on your stove, it’s not going to get to 240 F (115 C). So following a proper recipe and proper processing if you don’t do those things is the number one reason why lids come unsealed…..”
She also says that playing with the canning ring after processing, and incorrect headspace can cause lid failure:
Lids can also come unsealed if after you remove them from your canner… and notice your band is a little loose and you go, oh I’ll just tighten it a little bit, you’re actually affecting, as soon as you start taking that jar out of the canner that venting process is going on and it’s really working to get that tight seal and you adjust the band, you could prevent that from happening. Also too head space can cause things to unseal.” [2] Jessica Piper. Video: Canning Lids 101. 27:00. Accessed March 2015.
Turning jars upside down after processing can actually weaken or break the seals — if not then on the spot, then loosen them for long-term.
Why would it happen to careful canners?
Careful canners are not going to use an untested recipe, and are not going to water bath instead of pressure canning.
So are there any other reasons for the occasional jar coming unsealed on them?
The Presto company adds these reasons in its FAQ [3] Presto FAQ, accessed July 2015. which would perhaps be more likely to be a cause of seal failure for experienced, safe canners:
- Hairline cracks in jars permitted entry of spoilage organisms during storage;
- Loss of liquid during processing caused food particles to lodge on rim of jar;
- Thin or uneven layer of sealant on canning lid.
There’s two more possible reasons. The first is that home canners get set in their ways and don’t always like change. We’ve been told to no longer boil the metal canning lids, but many people are reluctant to stop doing that.
Ball says now that boiling the lids can weaken the lids and cause seal failures:
And most importantly too like I mentioned before if you boil you lids, they can get a false seal, or seal too early, and maybe there was an issue with the pressure and later down the road they can come unsealed.” [4] Jessica Piper. Video: Canning Lids 101. 27:00. Accessed March 2015.
The second reason would be re-using in error the one-time use only metal lids.
References
Anne
I have been canning food for over 30 yrs. I bought new jars and now hlids unpopping. Are they doing something different with the seals. Not all unpopped but some have after having a good seal. This is getting costly and Ive heard this from Many people saying the same thing.
Judy
The same has been happening to me! I have been using preserving jars for 50 years and it’s only the past two years this has been happening. Oh, maybe a jar or two in the past but last year I tossed about a third of the contents of the preserves into the compost. I’m tired of throwing away food I worked hard to grow and process. I hear the snapping of the lids and most do seal but later on, they are unsealed.
K L
Been canning zucchini relish for over 30 yrs. 8 jars did not hold a seal. This problem is only in recent years. Should I water bath longer than 15 min/pint or pressure can?
Joy Long
I just heard one of my canned jars ping open downstairs in our basement. I checked it out and yes, it lost it’s seal even when I canned correctly. I noticed it was 74 degrees down there. Is that too warm to store them there? Not sure what else I can do!
Laura Morgan
I am canning grape jelly. I have been canning for years and this is a first. I am using the recipe from the Ball Blue Book. I am using new seals and not boiling them. After taking them out of the boiling water bath I can hear them all pop and check after cooled and they are all sealed. Later in the day they come unsealed. Jars were sterilized. This has happened on two separate batches now.
Sherry
Exact same thing … never ever happened before – grape jelly from Ball canning. Such a waste of time and a lot of grapes. I have never lost a single jar of jelly. So
Heartbroken!!!
Healthy Canning
Are you processing the jars in a hot water bath?
Healthy Canning
Are you processing the jars in a hot water bath?
Wanda
Canned 26 pints of green beans two weeks ago. Went to use today and 14 are unsealed!! Been canning for 46 years, never had this happen!!!! What in the world??? They all pinged, and jars are good!
Healthy Canning
Please check with one of these Master Food Preserver help groups.
Becky burkhsrt
I have been canning for 40 years. This year for the first time ever I had 7 lids pop off after they had sealed. I was very upset. Are they changing the way the lids are made??
T Kuiper
Reading all the comments of people canning the same way for decades, sounds like the culprit for the unseal issue are the lids. Does anyone agree with this? Where are the lids made? Are all lids leaking? Any certain brand better?
Jackie
Same thing happens to me just dumped 9 qts do not boil lids
Tammi D Elder
Can you recan green beans? I had 3 qts. that unpopped after 2 days that had been popped, sealed already. They smell good.
Healthy Canning
Discard those they would be highly unsafe. Here are the procedures for handling spoiled jars: https://nchfp.uga.edu/how/general/identify_handle_spoiled_canned_food.html
Roanna Weldon
I have had the same thing happen with the Ball lids that I bought last year.. we just canned 24 quarts of hamburger and 18 quarts of stew meat.. and half of my jars have unsealed.
Penny Bell
Exact same thing is happening to me
unknown
10 minutes for tomatoes? you need atleast 40 minutes. Some call for 45 minutes. Did you have headspace? You need to follow the correct recipe as Mrs. M states. I work in a canning plant in the food industry. let me know if you need help.
Patty Hempen
I canned 10 quarts of carrots. They all sealed. I canned them in a water bath like my Kerr book said and I did heat the lids. Was unaware not to. After about 5-6 days 1 by 1 they are almost all loosing their seal! Makes me sad. I’ve been canning for 30 years and have never had this happen.
Healthy Canning
Carrots require pressure canning. It’s a good thing they lost their seal — they would be unsafe to eat. Frame your Kerr book as an antique, and grab a free copy of the USDA Complete Guide here: https://www.healthycanning.com/wp-content/uploads/USDA-Complete-Guide-to-Home-Canning-2015-revision.pdf . The recommendations have totally changed in the half-century or more since Kerr last published a book.
Randiss Hardee
Have been canning beans for more than 30 years. Always have one or two out of 10 to 12 cooking a year that don’t seal. This year, did two cookings and every one sealed. Then did 3 more and out of 21 jars, only 11 sealed. Did them just like I have done for 30 years and never had this kind of misfortune. I never reuse lids, and always check jars good for crack and such. Some simply didn’t seal at time of canning, others seemed to be sealed but after a few days, they popped loose. So heartbroken.
Brenda Robinson
This has been happening to me too. I don’t know what to do to stop it.
Juanita Short
A possible theory on increase incidents of seal failure??; I’ve had a whole lot more failures since BPA free lids have been produced. It has taken the joy & satisfaction out of canning my home grown/self harvested or even purchased foods. These failures are pretty costly in wasting my precious time and $$$$.
Cherie
Omg this has happened to me this year! I have never ever had a jar come unsealed by itself before this year and I’ve also had several not seal and I’ve gone over everything I possibly can and the only other thing I can think of and no one seems to ever question if the lids are good to start with! I would think that as with anything there would be some that are faulty and since I’m hearing of other people that it’s happening to it’s making me wonder?! Which brand of lids are failing?
sarah01
i canned 69 qts of half runner beans in the past two weeks. I have never had but a few jars come unsealed, and i usually can 70 to 90+ jars. This year almost half of my jars have come unsealed & I also have been canning for about 30 years. All my jars and 2-pc lids were brand new & Ball Brand… I told my husband the lids seemed a lot thinner. So very upsetting. I spent a small fortune purchasing new jars, lids and rings.
Beth
This just happened to me with potatoes. Did 4 quarts and one popped loose after probably 3 or 4 days. Now I don’t know what to do. If I should throw them out? It’s so aggravating after all the time you spend canning to think you may have to throw something out.
judy l
I made pickles this past August have used this recipe for years. All of my jars where sealed when I put them in my garage in a cupboard for storage. Was getting a jar for a Christmas gift and realized 3 jars did not seal. All where big mouth lid, the jars with regular lids were all good. Are the pickles good or do I need the toss them? There was a white film at the bottom of the jar when I shock it they almost seemed like sour pickles like my mom used to make.
The recipe I used is a hot broth and I do not pressure cook or hot bath the pickles after putting in the boiling broth in each jar. I always boil my lids prior to putting them on the jar also.
Healthy Canning
The jars lost their seal because the contents went bad. Either on their own, or because there was a weak vacuum seal that gave out and let contaminants in. Not processing the jars can seem to work — until it doesn’t work. It’s hit and miss. https://www.healthycanning.com/home-preserves-jars-must-processed/
I’d suggest contacting this Master Food Preserver group to ask them for further advice: they are quick to answer and very helpful. https://www.facebook.com/UCCE-Master-Food-Preservers-of-El-Dorado-County-456649991034665/
p.s. Since 1969, Ball has been advising NOT to boil the lids. https://www.healthycanning.com/sterilizing-canning-lids-jars/#do-not-boil-canning-lids-not-even-to-sterilize-them
Latisha curry
What happened? ?? I canned several cucumber for pickles some stayed sealed and some didn’t. What did I do wrong
Healthy Canning
Hi Latisha, I’d recommend contacting a trained volunteer in one of these help groups and they will walk through it all with you: https://www.healthycanning.com/master-food-preserver-help-groups/
Ashley
I canned some candied jalapeños and now I see the screw lid around the flat piece s loose and I can move it. Is this bad? This was not the case with my jellies.
Healthy Canning
Yes, the jar has gone bad. Dispose of the contents. To discuss why this could have happened, consult with a volunteer in one of the Master Food Preserver groups here: https://www.healthycanning.com/master-food-preserver-help-groups/
Robert Wade
After 24 hours you can remove the rings (screw lid).. double check the seal on the lids.. Press on the lid.. It should not move. Tap them gently with a finger nail and a good lid has a unique sound you can’t miss.. Also lift by the edges of the lid and it should stay tight At this point, wash your jars and label.. Don’t put the rings back on.. IF they jars do come unsealed, it is possible that a false seal will form and you won’t know that you had a seal failure. The rings are on just to keep the lids in the correct position for them to seal in the canner.
Sherr
Canning sites on Facebook are warning of Ball lid failures. This is wide spread with by the book canners. Something is wrong with lids. I will return mine. Can not afford to can with this junk.
Faye Loveless
I canned 21 jars of green beans in a water bath a week and a half ago. My house sounds like popcorn popping last night. I had 13 jars that the seal broke, don’t have no clue why
Healthy Canning
Faye, I’m going to suggest that you take your problem to one of these Master Food Preserver groups. They can help you step through what might be the cause: https://www.healthycanning.com/master-food-preserver-help-groups/
Kim Robinson
Hello!
I’ve just discovered that a large batch of dills i made have “popped” lids.
Can I do anything to salvage them or do they all need to be tossed?
Also, there are a few jars that are fine. Can I assume they are safe?
Thanks for any advice!
Kim
Healthy Canning
Please contact the Master Food Preservers of Eldorado here, they will walk with you through it: https://www.facebook.com/UCCEElDoradoMFP/
Linda Waters
Canned 12 pints tomatoes 2 1/2
weeks ago. Had 1 jar unseal after all this time. Now I’m afraid to eat any that remain sealed for fear of botchalisum. Please help. I used 10 min water bath.
Healthy Canning
Hi Linda, sorry just saw this. Please post your question to the Master Food Preservers over at https://www.facebook.com/UCCE-Master-Food-Preservers-of-El-Dorado-County-456649991034665/ and they will help you to review the situation.
Mrs. M.
Probably because there are no tomato recipes with a 10 minute water bath time. That is why your jar of tomatoes unsealed. Bacteria and possibly botulism has grown in your jars. I would throw away all the rest of your jars of tomatoes and follow a tested recipe with the correct amount of time.