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Don’t Let This Happen to You. This is How to Tell if Your Jars are Sealed.

A friend of mine recently gave me a jar of jam. Someone had given it to him, and he doesn’t eat sweets. He knew I made at least one kind of jam every year, so he gave it to me under the assumption that I eat a lot of it. Honestly, I eat peanut butter and jam sandwiches three or four times a week, so it was a good call on his part. He knows me pretty well.

The gift was a beautiful rich purple blackberry jam. I was really looking forward to slathering that on my peanut butter sandwich a few days ago. However, when I unscrewed the ring, I knew immediately that I could not eat this jam.

unsealed jar

The jar didn’t properly seal during the canning process, and jam leaked out from beneath the flat coating the rim and ring. It would have been dangerous to consume what was surely delicious jam because bacteria grows in unsealed jars. Eating something from a jar that didn’t properly seal can make you extremely ill and in some cases kill you. If you ever have a jar that doesn’t seal after 24 hours, immediately put it in the refrigerator where it will stay safe to eat for a few months.

There are many reasons that jars fail to seal. She could have had a bad flat. She may not have gotten the rim of the jar wiped off well enough before installing the flat and ring. The jar could have been flawed. She may have overfilled the jar and caused her jam to boil over onto the rim. She may not have gotten the ring tightened enough. The jar may have been disturbed before it could seal. You really need to let your jars sit for a good 24 hours after processing before putting them away.

jam covering rim

The way you can tell if your jar is sealed or not is if the center of the lid is concave. The below picture shows a properly sealed jar of my homemade pear jam. I hope you can see this okay. The lid is concave instead of the the center being rounded out. You can also tell whether the jar is sealed by unscrewing the ring and trying to lift the flat. If it doesn’t budge, you are good to go.

sealed jar

I just took a batch of salsa out of the canner, and not all of my jars have sealed yet. Below is an example of a jar that hasn’t sealed. Notice the little circle in the center is puffed up. Once the jar seals, it will be pulled down. You will hear a loud popping sound when the jar seals. Four of my eight jars have sealed so far. Some jars pop immediately while others take several hours to announce their success.

salsa unsealed

Canning is a lot of work and very time consuming. I personally find great satisfaction in preserving summer’s bounty to eat later when nothing is vine ripened. Anyone can have a bad seal. It’s happened to me a couple of times. You just have to make sure to check it out before eating it or giving it as a gift.

I give my home-canned goodness as gifts to many of my friends and family during the holidays. I make everything with love, and want to share it. Some of those close to me even put in requests. My nephew asks for my salsa every year. My best friend adores my pear butter, and offers to take any extra off my hands. It makes me happy to share the fruits of my labor. Remember, love is the secret ingredient to the best cooking. Just make sure those jars seal.

Thank you for reading Ozarks Maven! If you enjoyed these seeds of wisdom, please subscribe to my blog, Like Ozarks Maven on Facebook, or follow me on Twitter @OzarksMaven.

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