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Nov 18, 2009 12:41 AM

eeeek: urgent homemade jam food safety Q

Help! My husband and I made blackberry jam a few months ago. We brought some jars out of storage in preparation to bring them to family and friends over thanksgiving. However, my husband noticed that some of the jars are oozing jam. The lids' dimple is still depressed. Are these safe to consume?

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  1. If you took all due precautions in sterilizing the jars and caps and boiled appropriately afterward, it sounds as if they were filled too high. If the dimple is still depressed, you're not getting any gas in there from decomposing bacteria. That's good. However, the best way is to open one up and sniff and taste for anything amiss.

    NB: This is an educated guess from the son of a jam, jelly and preserve expert. My dearly departed dad could have written you tomes on your question.


    1 Reply
    1. re: Chefpaulo

      I agree that they were probably overfilled but I would make very sure when you open them to check that you did indeed have a seal. Listen for that slight hiss when you break the seal on the lid. If the lid lifts right off with no effort the odds are you have no seal. A sniff and taste test is not sufficient to determine whether or not the jam is still good. Some very nasty critters can't be detected that way. If in doubt, toss it.

    2. Sugar and acid are both pretty wicked preservatives. I would eat 'em -- shoot, the human race somehow survived the days when paraffin and oiled paper were the "lid" on preserves. ;)

      1. I'd feed some to the dog first.

        No, I'd feed some to someone else's dog first.

        No, really, I'd toss any jars that are oozing. Even if you overfilled them, there's no good reason why the jam should expand after it's been removed from the cooker, and regardless of how the dimple feels now, I don't see how jam could ooze out if the seal were truly intact.

        I'm the first to agree that many people worry way too much about some food safety issues (full disclosure: I don't always cook pork to 160F, make salad dressings with raw eggs, and love tuna tartare). Lauragrace is right in general, although I suspect there were just a few members of the human race who did not survive that last jar of jam sealed with parafin or oiled paper. But Morwen is also right. If food poisoning had a distinctive taste, nobody would get food poisoning.

        1. I would eat it. You did not leave enugh "head space" when you filled the jars and they oozed when you boiled them. Since they are sealed, the ooze apparently did not interefer with the rubber gasket and they are probably fine. The big spoilage factor for jam is mold - which is usually quite visible. The high acid and sugar content make them pretty safe - as one poster pointed out, my granmother taught methe parafin eal and I did it fro years with no adverse conequences.

          1. I'll have to chime in with LauraGrace and Junoesq. Sugar and acid is not a bacteria-friendly environment. If you were canning any animal product (pickled eggs, pickled pigs feet *yuck*) and your jars were seeping, in the hopper they'd go. But high sugar content is a safeguard in itself.

            My family owned the American Preserve Co. in Philadelphia from 1912 to 1956. Dad was Vice President and chief chemist from 1939 until the company was sold. When I was about seven,I remember showing him a half empty jar of raspberry preserves that had been in the fridge for quite a while. It had some white mold on top and I asked if I should throw it out. Dad assured me that the mold was surfactant (my new word of the day) and that it just needed to be scraped off the top and all underneath was fine. He then did so and put the unaffected jam on toast. No ill effects and he lived another 43 years.

            I really think you just overfilled them and that nothing insideous is in there.


            2 Replies
            1. re: Chefpaulo

              In a home canning situation overfilled jars are apparent as soon as you pull them out of the waterbath. They will either be already oozing or if the preserve has washed into the water the sides will be sticky when the water dries. My concern is if they didn't notice this upon pulling the jars out or putting them away, something may have been wrong in the recipe. For example, if using a regular pectin or no pectin, not enough sugar to reach a preservative level or jam/jell set, or undercooking. In any case what could have happened was the creation of an anaerobic environment for ferment (sugar is the food Acetobacter bacteria eat) which would explain the later seepage, pressure formed by the ferment forcing the jam through the seal. What they have could be innocuous or maybe not. I stand by not taking a chance. If what wasn't seeping upon being stored now is seeping I'd throw it out. Like Clint says, "ya gotta ask yourself, do ya feel lucky?"

              1. re: morwen

                Oddly, it was the recycled bon maman jars that have had the problems, particularly after flying. We used preserving sugar with extra pectin for soft fruit (and actually over cooked it).