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Jan 13, 2009 03:19 PM

Microwave Sterilization?

If I put a washed canning jar into my unit and zap it, will it be sterile upon removal? If so, how long at highest setting?

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  1. This wouldn't work.Microwaves need something to latch onto to
    vibrate and turn to heat.This is usualy something like fat,sugar,
    water etc.Microwaves will not heat glass.If the jar is put in wet
    the water on the glass will evaporate before heating up the glass
    enough.I usually run my jars through the dishwasher and then put
    plastic wrap over the ones I will not be using right away.

    1 Reply
    1. re: rdch

      "...need something to latch onto to
      vibrate and turn to heat..."

      Exactly. Will my Microwave "latch onto" bacteria?

    2. If you are going to use the jars for canning, you do not need to sterilize them. Just wash well. They will become sterilized in the canner...BWB or PC. Don't waste your time.

      1. Sorry about the brief post.I was tired and in a hurry so I condensed It.
        What I also should have added was that microwaves in an oven are not uniform
        in their heating patterns so although you would probably kill some of the bad
        guys there would be some survivors.This would probably not be considered good
        sterilization.Also the bad guys would not have much mass so most of the
        microwaves would not be absorbed.This would probably be equivilent to running
        the microwave empty and over time this can damage or destroy some microwave
        ovens.If you email your ovens manufacturer you will probably get a better
        answer.Bernardin would be a good place to email about this but their site
        ( has been down for a couple days.I don't know when it will
        be back up.

        interesting link(slightly off topic


        2 Replies
        1. re: rdch

          Thanks, rdch. Couldn't link to Home Canning, but I get the idea from the ants.

          In response to your post, billieboy, some of our stuff is not canned per se, so it's not processed in a canner. We're talking things like pickled mushrooms, hot pepper jelly and the like. The food comes off of the stove and into cleaned jars that have just come out of 375* oven. The jars are hot and I thought that nuking them would be easier and leave us a cool, sterile jar to work with.

          Thanks, both for your advice.

          1. re: DockPotato

            I used to make jam (don't have a garden any more) but I used to dishwash my jars, then just before pouring hot jam into them , I would pour a little boiling water into each jar with a spoon sitting in them to absorb the heat, then pour out the water and spoon in the jam.

            never got mold in my jam and didn't die of botulism!