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Jam-what am I doing wrong? Will I die?

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Ok, this is several questions in one about homemade jam.

My friend gave me some homemade jam about 3 weeks ago. It's one of those big pint jars, which I knew I wouldn't be able to finish, so I asked them to give me the jar that they already partly used up.

They canned the jars, did the sterilization process, etc. etc.

This morning, I had some with my yogurt, and I noticed after the fact that one of the areas had already developed mold. Ugh.

So my questions (since I can never seem to finish a jar of jam without it molding)
1. Will I die from botulism from this morning's experience?
2. The mold typically grows on areas of jam that are either stuck on the walls, etc. Maybe I missed this, since we never really did this while growing up, but am I supposed to meticulously scrape off any remnants of jam off the walls of my jars every time I have jam?
3. I hate wasting food, but I hate the idea of dying from botulism even more. :) Can I just discard the area that was contaminated with mold and then proceed using the other uncontaminated areas?
4. I don't think my jam-eating rate is that ridiculously slow, but all of the homemade jams I've ever received (except this one plum jam that I receive from my friend every year) have never lasted more than a month or two before it starts to mold. Is there a way to prevent this? I just made pint-sized containers of apricot jam, and I'm afraid to open it lest it start to mold before I manage to finish it all.

FYI, these are full-on sugared jams.

Thanks much.

The Jam Idiot

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  1. Can't answer all your questions but I just scrape the moldy parts off the lid or sides of the jar and eat what isn't moldy. Still here and healthy.

    It's not that onerous a process. A quick wipe with a paper towel or scrape with a spoon is all I ever do. Done in seconds.

    1 Reply
    1. re: three of us

      Great. Now I know I can eat around the mold (kindof like cheese. Heh heh). Actually, I ate my mold-contaminated jam yesterday and I'm fine, so I guess it's ok.


    2. My homemade jam lasts a lot longer than that. Do you keep it in the fridge? It also helps if you always use a clean spoon to put it on your toast, rather than using the knive you've used to spread it with, ifyswim.

      3 Replies
      1. re: greedygirl

        Absolutely. I mean, heck, I even refrigerate tomatoes (I know that's sacrilege, but my apt. gets really hot during the day, so if I can't eat them before they start getting soft, in they go.) And I always use a clean spoon. . ..

        Maybe I should start freezing it.

        1. re: anzu

          Refrigerating tomatoes permanently kills the tomato flavor molecule, Z-3 hexenal. Put them in the coolest place you can find that's not the frig -- in a bowl or plastic container in a deep drawer, or someplace cool and cover them with a towel. You should get some extra days of life this way. Just don't refrigerate them -- that's tomatocide.

          1. re: anzu

            I make jams when fruits are abundant and use very little sugar. They've kept pretty well by using clean utensils and storing in small jars. And, *gasp* I have frozen them with no harm done for 6 months or so (when it got eaten up, not thrown away). So by all means, freeze away.

        2. I always scraped mould off homemade jam and haven't died yet!

          1. Botulism is mainly a risk with low-acid (high-pH) foods such as canned vegetables. Acid and sugar retard the growth of bacteria. According to the CDC (http://www.cdc.gov/nczved/dfbmd/disea...), "Foodborne botulism has often been from home-canned foods with low acid content, such as asparagus, green beans, beets and corn. However, outbreaks of botulism from more unusual sources such as chopped garlic in oil, chile peppers, tomatoes, carrot juice, improperly handled baked potatoes wrapped in aluminum foil, and home-canned or fermented fish." No mention of jam.

            Pickyourown.org (http://www.pickyourown.org/canningqa.htm) says:

            "If I find mold growing inside a jar of canned food, can I just scrape it off and eat the food?

            Mold growth in foods can raise the pH of the food. In home canned products, this could mean that the high acid products could become low acid and therefore run the risk of botulism or other bacterial spoilage. Thus, any home canned product that shows signs of mold growth should be discarded. The exception to this is jellied products. (where sugar is added). In these the high sugar content would prevent the growth of Clostridium botulinum. In jellied products, remove any surface mold plus 1/2 inch of the good product underneath and then use the rest immediately. Jellied products with extensive mold should be discarded."

            1. Also, I think jam with a lower sugar content goes mouldy more easily, but I could be wrong.

              2 Replies
              1. re: greedygirl

                I think you've hit it. Sugar is a preservative. Whenever I make jam, I'm ever so slightly tempted to skimp on the sugar. I think something in my brain goes "but it will be healthier that way!" Silly, I know. But I've never acted on that. It's the sugar (usually fruit:sugar ratio about 1:1 in weight) that keeps the fruit from spoiling. I wonder if other people making jam use less sugar than necessary.

                I also usually use a bit of lemon juice. It can perk up fruit that's not so flavorful, and plus I figure the extra acid can't hurt in terms of preserving.

                By the way, I don't keep my jams in the fridge, and I don't scrape the bits from the sides of the jar. Have never had mold.

                1. re: Kagey

                  I make low sugar jam every summer (nowhere near 1:1 ratio) and I don't have a problem with spoilage. (I have less-sweet, more fruit jam and the color doesn't keep as well. I always add lemon.) Usually an open jar of jam in my fridge is gone in about 2 months.

                  I can't imagine scraping mold off my jam and eating it. I'm sure it wouldn't kill me, but YUCK.

              2. Lots of sound advice here. I have been making/eating homemade jam my entire life, and very seldom (like practically never) have a problem with mold when I store the jam/jelly in the fridge. I second the recc to use a clean spoon to serve the jam from the jar, then a separate knife to spread it. Maybe you should check the temp in your fridge to make sure it is keeping things cold?

                By the way, botulism is not visible. Visible molds tend to be things like penicillium that don't produce toxins, in fact, some of them produce antibiotics like penicillin!

                1. Everyone has already said it - mold and botulism are 2 different things - I kinda expect mold to form eventually in a high sugar/high acid thing like jam, but never clostridium (the organism that causes botulism). The presence of mold is not bad, but I do not usually get mold in my jams or jellies. Could be in your house and they get in when you first open them up. Not serious except for people with mold allergies and I expect that they are in only the exposed portion of the jam not inside the jam. If on the inside - you are doing something wrong and I would revisit your technique.

                  1. The problem with molds is that there are millions of different strains out there and you have no idea which mold has taken up residence in your jar. Do you have some miracle like penicillin which will cure you of whatever, or do you have one that will make you ill.
                    Some time ago we were warned that cutting off the visible mold on cheese was not an answer as you have no way of knowing how deep the tendrils have reached. I would assume that goes for mold in jams.
                    Mold is not like botulism. Botulism requires low acid (most fruit has acid) and an anarobic condition. Since the jar of jam has plenty of air, that should not be a problem.

                    1. Wow. Thanks everyone for the info re: botulism vs. mold. The botulism, I brought up, b/c I once asked my friend about mold and she was like, "throw it out! Don't you know you can get botulism from moldy jam?" So I now associate moldy jam w/ botulism. Thanks for setting me straight. :)

                      As for all the people who mentioned they don't get mold, I'm really puzzled. There is one jam that I get from a friend of mine-- it is the lowest sugar content of all of the jams I get, and that jam never ever molds (I've been getting her jams for 6-7 years and it takes me anywhere from 3-6 months to go through one jar, but it has never molded).

                      But the jams that have molded have been from about 3 different sources. The latest was a plum jam that was made less than a month ago, w/ standard (high) sugar content. In fact, it's so sweet, I've had very little of it so far (a little going a long way). At this rate, I might finish it by next April. :)

                      I have been using clean spoons, but maybe I'll do as others suggested and use a separate utensil to handle it.

                      Hmm. There seem to be mixed feelings about whether I can still use the jam, but given the sugar content, it sounds like it's safe to use if I scrape the surrounding area.

                      4 Replies
                      1. re: anzu

                        Maybe where you live in CA, there are special molds that thrive in high-sugar environments. :) How did your low-sugar jams work out, btw?

                        1. re: cimui

                          Oh thanks for asking. :) Well, we ended up doing the full-sugared version, which I think was 1.25 cup sugar for every 2 pounds of fruit? I did send my friends the link of you saying that we don't need sugar, but I was outnumbered by people who wanted to follow an "exact" recipe. Ah well. I have 3 jars of this sitting at home, but I'm afraid to open it, until I can figure out ways to minimize the mold onset so soon. Plus we made pint-sized jars, which will be twice as hard to go through (the jars that mold are usually 1/2 pint or smaller). :)

                          I think I will open it once I get through my mold-contaminated plum jam, which might take me a few more months to eat up. :)

                          Your theory is perfectly plausible, since none of the jams I make ever seem to mold so quickly, and I make almost all of my jams low to no sugar. However, I also have an inversely proportional correlation between the sugar factor and consumption factor, so it's likely that I'm devouring the almost-all fruit ones much quicker. :)

                          1. re: anzu

                            If you need a way to use up a lot of jam quickly (or a means of cooking any l'il buggers in there -- real or imagined -- to death), I really like this recipe:


                            and i really like the pictures here, though I've never tried the recipe:


                            1. re: cimui

                              Ooh. I think I'm going to keep my second jar of jam around after all! Wow. I could even make this in the winter! Thanks!

                      2. Mold can sometimes enter the jam -- the most likely way I think -- via a spoon that was previously used on another foodstuff, usually at the same meal. Meaning, it's not the jam that grew the mold, or the amount of sugar used, but the tiny amount of food that was on the spoon that was transferred into the jam that grew the mold.

                        This may be especially true of a "partly used" jar of jam as yours was.

                        Usually jam doesn't develop mold on its own, because of fruit's high acid and the powerful preservative action of sugar. Just scrape off the mold, and proceed without fear.

                        1. In addition to using clean utensils, keeping your jam refrigerated and good advice....why not use up your jam?

                          I don't have toast that often, but jam can be used to sweeten plain yoghurt, on french toast/pancakes/waffles, over ice cream, to glaze roast chicken or pork or chicken wings, to make a glaze for casseroled meatballs, dolloped in muffins (especially good in cornmeal!), thinned slightly to sweeten homemade granola, to 'seal' a piecrust before adding the moist filling, to seal cakes before icing.....