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Home canning debate

I recently learned how to can and made some great jams, pickles, and preserves from excess fresh summer produce. But the first batch I made, I didn't boil or bake the mason jars before adding the preserves and sealing them. I washed them, added the contents, and then sealed in boiling water for at least 20 minutes.

Obviously there's the huge risk of botulism here, but knowing that I have been keeping these jars in the fridge (away from my properly canned and trustworthy deliciousness). Because they are refrigerated, I say that the preserves are fine. No different than, say, cooking something and leaving it in the fridge. But my sister says that the sealing process (20 minutes under boiling water), could make botulism grow and that, even though they've been in the fridge, I shouldn't touch them.

Which of us is right?

(Of course, now that they've been in the fridge for two months, I'm not even sure I want to go in there anymore, but that was a lot of delicious produce I'd hate to see go to waste, so advice requested).

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  1. What were you canning? That makes a pretty big difference.

    1. We were canning: plum preserves, sweet pickles, peach preserves, and orange-current preserves.

      1. Normally I'm the Voice of Doom where botulism is an issue but in this case, botulism isn't a risk assuming you used a reliable recipe that called for water-bath processing. [Edit] Or more precisely, not boiling the jars presents no additional risk of botulism. Sterilizing the jars beforehand may protect against some bacteria and molds, but it will never destroy botulism spores anyway, boiling water just isn't hot enough for that. Your preserves sound like high-acid ones, which are inherently safe from botulism even with simple water-bath processing.

        Botulism aside, I'm no expert but I'd personally go ahead and try them assuming the lids remained properly/tightly sealed.

        3 Replies
        1. re: MikeG

          Exactly this. Now if we were talking green beans and carrots, I might have suggested a new fridge! ;)

          1. re: MikeG

            Agree with the above. Assuming that you used a conventional recipe that is acidic, poured the hot liquid in 8-16 oz jars and processed immediately they should be fine. You essentially boiled the jar by processing for 20 min. I make small batches of preserves, put them in clean jars and just keep them in the frig. I use them over the next several months.

            1. re: MikeG

              Agreed. 20 minutes sterilized those jars - because 10 minutes will. But you should put your preserves into hot, sterilized jars next time.

              As long as you followed recipes re acid, check the seals and eat.

            2. One thing to keep in mind is the bacterium that causes botulism is very common in soil, but it is not typically floating around in the air (except maybe on a very windy day). If it gets into your jars of jam, it's coming in with the food being canned (or maybe your dirty hands if you were sloppy), not on the jars. Even if your jars were not perfectly clean, the worst thing likely to get into your jam is some random mold, which will ruin the taste, but not your day.

              Bottom line, washing the jars in a dishwasher, or thoroughly by hand is fine. 20 minutes processing seems a bit short if the contents were cold, but if they went straight from stovetop to jars, I guess that's ok if that's what the recipe says. As MikeG noted, if you can low acid, low sugar veggies, stovetop processing is not a good idea, but jams, preserves and pickles are ok.

              1. No worries....the official answer from the USDA is that the jars don't need to be sterilized if your process time is >10 minutes. http://www.uga.edu/nchfp/questions/FA.... Also, you should know you can NEVER get botulism from most canned fruit products or pickles because the pH is <4.6 for most fruits (except figs, I think) and a properly made pickle that has the right brine strength for natural fermentation OR using vinegar in the brine. You can, however get botulism from tomatoes.....their pH can be higher than 4.6 so you must always add acid to canned tomatoes processed in a boiling water bath. Everyone thinks tomatoes are more acidic than fruit and that isn't the case. Hope this helps!

                1. I'm planning to make my own mincemeat for mince pies this Christmas, and will be storing it in jars. Most of the recipes I've looked at (BBC, Delia, David Lebovitz) tell you to put the mixture into sterilised jars, cover with a waxed disc, put the lid on and stick in a cupboard - no mention of post-boiling in a water bath or pressure canner. I've read through many of the old threads on here and everyone agrees that the post-processing is imperative to remove the risk of botulism. Is the difference that the mincemeat will be used up relatively quickly between now and Xmas? If I was making it for future Xmases to come, would I need to boil it after jarring?

                  Thanks in advance,


                  8 Replies
                  1. re: gembellina

                    The waxed disc stick in cupboard method is the usually acccepted British method of putting up jams, jellies, and sweet preserves. It used to be a standard practice here in the States a generation or two ago and a lot of home canners still do it. USDA recs changed about 30 years ago on that being an acceptable practice (which is about how long I've been canning). Back when I started canning I tried the paraffin seal but found it to be messy, somewhat dangerous (as in wax can flame if it gets over heated and drippy wax bits burn your hands), it took longer than waterbathing (pouring repeated layers of wax per jar to get a thick disc), and the damn things still wept syrup and attracted ants and rodents, not too mention that when the wax seals got dusty you couldn't just wipe the dust off. Take the time to process it if you want it shelf stable.

                    What your mincemeat contains affects how you process it. If it's an all fruit recipe, with a good bit of acid (vinegar or bottled lemon juice) then it can be water bathed. If it's a traditional mincemeat containing meat and suet, then it should be pressure canned. If you're planning on using it all up between making it and this coming Xmas you can store it in the fridge. Any longer and it should be processed by the appropriate method or frozen.

                    If you're making large batches for future use next year I would recommend processing it because mincemeat (both types) actually improves in the jar with age. But use it up in a year to a year and a half.

                    1. re: morwen

                      Thanks, that's really useful. I thought the British recipes were suggesting a disc of wax-coated paper (and maybe they were) but I can see that that wouldn't create a sufficient seal. I'll stick to making a small batch and eating it up quickly!

                      1. re: gembellina

                        This is how I always preserved jelly and jam, easily several dozen jars at a time. The wax pour was done in only 2 rounds. You wiped all the rims of the jars to make sure they were clean and let the jelly set up. When ready to seal, you poured a layer of paraffin, let that set up. Then come back and finish the paraffin, kind of tilting each jar around so this 2nd layer of paraffin so it would complete the seal. You had to be careful not to make the paraffin layer too thick as it would tend to break the seal as it shrank when setting up. Too thin would also tend to break the seal. I never had any weeping or seeping, but occasionally an incomplete seal would occur. These would be put in the fridge and would be eaten first. Sometimes we would miss one; then I'd open up a new jar, find some mold, and we would scrape that off and eat it anyway. I would not do that now, but it was common practice and "normal" for my depression-era parents.

                        As for dust, I always covered the jar with a stamped tin lid. These were quite common, made to fit the old style tapered jelly jars. My grandmother would use a piece of twine to tie scraps of quilting material to keep the dust out. The jars were tapered to help prevent air bubbles forming along the sides of the jars - they'd float up instead of "sticking" to the sides of the jars. You'd run a knife around the inside of each jar to make sure no air bubbles lurked while the jelly was still hot. Once the paraffin seal was complete, the jars went back in the boxes they came in and were stored on shelves in the basement. I haven't seen either jars or lids in years. I can't even find pictures that really look like them, not the ones I remember at least. We reused the paraffin for candles.

                        At one point we had a 5 year backlog of jelly. 2 grape vines, 3 apple trees, 3 crab apples, a quince that had been trained to a small tree; mulberries; plums. Made for a lot of jelly, even for a family of 7. Jelly and preserves were dated so we always knew what to eat first. We would give gifts of jelly one year back to make sure we didn't give away anything that hadn't sealed properly. It was a lot of work, and it was something I both looked forward to and dreaded every year. I kind of miss it even now.

                        1. re: ZenSojourner

                          that's a lot of jelly! I love the idea of canning on a large scale, it seems so homely (and I mean that in the British sense of the word). But currently I don't even have a windowsill so it'll be a while before I can grow an apple tree!

                        1. re: morwen

                          A while back (maybe 20 years ago) I made and canned a large batch of meatless mincemeat to gratify my husband's craving for thanksgiving mincemeat pies. Used a Farm Journal recipe for pear mincemeat subbing in half apples. It was still satisfying him on the fourth thanksgiving later.Ive switched over more recently to doctored up commercial stuff, but its a worthwhile project if you have a time.

                          My parents used to use paraffin to seal their jams - dont remember any pests, but they long ago shifted over to lids and rings and waterbath processing. Paraffin tops are probably a rational use for those pretty cloth toppers that seem so pointless on commercial jams.

                        2. re: gembellina

                          You won't need to boil mincemeat after bottling. I usually use the Delia recipe, and the fruit is covered in fat whilst its cooking on a low heat for (IIRC) around 3 hours or so. You're more likely to get fermentation with mincemeat.

                          The wax disc is really to provide a barrier between metal lids and the contents - if you have jars with plastic coated lids you don't need to do this.

                          Most people I know who make mincemeat here in the UK keep it for months (a lot of people make mincemeat this year for next year's pies) with no problems. And you can bet your bottom dollar that if there had been food poisoning from this, it would be all over the press!

                        3. With what you canned - acidic items - you're probably okay. It's low acid foods with a ph greater than 4.6 that are worrisome. This includes vegetables sans vinegar, meats, figs, some tomatoes, etc.

                          You really can't kill botulism spores with boiling water; it's just not hot enough. This is why folks who can low-acid foods use pressure canners that get between 240 & 250 degrees. (The time inside the canner depends on the size of the jars, the foods inside of them, and the altitude of your stovetop.)

                          Incidentally - sterilizing your jars in boiling water beforehand would not prevent botulism spore contamination. The temperature simply isn't hot enough, unless you are using a pressure canner, and botulism contamination usually comes from the produce itself. (Generally the spores don't float around in the air willy - nilly. They're brought in on the vegetables, really dirty hands (ew), etc. Botulism grows in low-acid, anaerobic environments which is why eating fresh vegetables is fine, but eating improperly canned vegetables is not... Sealed jars of green beans in water is pretty much botulism spore heaven.

                          I don't think that 20 minutes under boiling water will make the spores, if present, grow - however I also don't think you have anything to worry about, given the contents of the jars. They are probably acidic enough.

                          I would eat them.

                          (BTW - if you're worried, you can purchase ph strips that will tell you the exact ph of your refrigerated jars. There was a thread about doing so here: http://chowhound.chow.com/topics/649403)