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Jun 23, 2008 10:44 AM

Canning question

My friend and I made jam for the first time yesterday. We were reading some posts and decided to sterilize/seal the jars by putting them in a 200 degree oven. We filled them up and they all sealed nicely. My friend is now freaked out that we might get sick. To be cautious we both put our jams in the fridge today. Do we have anything to worry about? Will the jam be a-ok if we keep it in the fridge? Thanks!

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  1. I think you should be fine, however...

    I do some canning, mostly pickles and pig tongue or pork hocks. I haven't read or practiced enough to consider myself an authority, but I will say a few things;

    Usually jars (and lids and lid rings) are sterilised in boiling water. Also, the product you are canning many times are brought to boiling themselves, then added to the freshly sterilised jars. Finally, the cans are sometimes processed, that is closed, sealed, and placed in boiling water for 10-20 minutes, depending.

    So that said, I don't know if your jam mixture was boiled nor if you processed the finished product. If you had, I'd bet the product was quite stable and safe storing at room temp.

    Regardless, placing them in the fridge really should be OK and safe.

    When I do pickles, hot packed and processed, I'll leave them at room temp until opening and have had no problems. Although I have also cold packed others (to keep crispness) and simply stored them in the fridge.
    When I do meats, I just pop them in the fridge until ready to eat. I don't trust myself enough for those...

    1. Did you just sterilize the jars in the oven or did you seal them that way? To be shelf stable, jam should be processed in a hot water canner for 5-15 minutes (depending on jar size) to guarantee a vacuum tight seal, according to the USDA. I know the USDA does not recommend oven sealing at all. However, lots of older recipes just call for hot jam and clean jars and lids. The heat from the jam will frequently soften the sealant enough to seal the jars, but it is a bit iffy. Jam is pretty forgiving, though; its high sugar and acid content make it safer is the seal is imperfect--compared to peaches or tomatoes.

      So to be safe--test the seals: take the bands off and try to open the lids with just your fingers prying. If you can pop the lid with your hands--you need to keep the jam in the fridge or freezer or reprocess it correctly. If you can't budge the lids, they are probably ok. I wouldn't give the jam to anyone very old or very young or with a compromised immune system, just to be safe.

      5 Replies
      1. re: dct

        Another test is to press down on the center of the lid. It should be rigid with no give. If it pops up/down, you don't have a seal. If you did not process in a hot water bath, keep an eye on the jam, even if refrigerated. Without a proper seal, the jam will mold within a few weeks.

        1. re: TNExplorer

          To answer some of your questions (I'm the "freaked out" friend):
          1) We didn't sterilize the jars in the oven (it was only heated to 200 degrees) we just used that to seal them.
          2) There is a tight seal as when we press down in the center of the lid, it doesn't pop up/down.

          I guess our best bet would be to keep them in the fridge and just keep an eye out for any mold?

          1. re: AnjLM

            I don't think you have to "freak out" AnjLM, its pretty much the same as making the jam and plopping it into the fridge in say, a tupperware container.
            Use it up in a week or two, and you'll be fine.
            How many times did a previously opened commercial jar of jam sit in your fridge only to find it moldy?
            OK, the commercial jams are chock full of preservatives and stuff, but still, moldy; simply throw out (except my mom, who would scrape it off and use it anyway).

            1. re: AnjLM

              In the future, if you have a dishwasher, you can sterilize the jars by running them through a cycle, timing it to end when your jam/jelly is ready to be poured in the jars. Saves on space on the stovetop. I put the lids and rims in a big bowl and pour boiling water over them from a tea kettle. You can also hold your sterilized jars and lids hot in the oven if your timing is off. Processing them in a water bath is an absolute necessity as far as I'm concerned if you want to store them at room temp. It can take some time (up to several hours) for the jars to seal after they come out of the bath because the vacuum is created as the jars cool. You'll hear them "pop" if you listen for it. To test the seal, press down on the lid as suggested and also look to see if it's concave. I wouldn't recommend trying to test the seals by pushing the lids with your thumbs because that's the way I open my sealed jars normally. I don't want to bend the lids. I know you're not supposed to, but I reuse my lids if the sealant is still good and plentiful and there are no nicks or scratches anywhere.

              You can reprocess your jam if you want to shelf store it by bringing it back up to the boil and then going through the sterilized jars/water bath procedure. I've had to do this on occasion and have not noticed it to affect the quality of the jam/jelly. But it should keep nicely for you in the fridge for quite a while or you can freeze it. If you've made a huge batch and feel the need to use it quickly, make jam cakes and freeze them, use it in vinaigrettes and as glazes, thumb print cookies are nice and can freeze, lots of uses beyond the standard bread/butter or pb&j.

              1. re: morwen

                Thanks for the all replies. I'm feeling better about the jam and will keep it in the fridge to be safe. Although at the rate that my friends are eating the jam, it'll be gone in a few days!

        2. Jams and fruits with sugar are high-acid, and are recommended to be processed via boiling water bath. Oven canning does not provide a consistent result to be a reliable method. The jars sealing is not the be-all, end-all answer to something being "perfectly canned."

          This being said, fruits with sugar and/or high-acid foods spoil by turning moldy. You can see, smell, and taste the mold, and while nasty, it won't kill you. (unless you are highly allergic to penicillin, but that's another story entirely...)

          The biggest drawback to oven-canning for fruits with sugar and/or high-acid foods is that you have a greater chance of spoilage. All that work would be wasted.

          Your choice. Keep this batch, see how it lasts, and then next year, do the right thing and use a boiling water bath.

          For low-acid foods and vegetables or meat, PLEASE use proper pressure canning methods!