What's floating on top of my syrup?

[RobbieH]

would bringing it up to a boil kill any spores that might be there?

[JoeJ]

The researchers who have studied "the mold in the syrup problem" say that even though reboiling the syrup will most likely kill the mold spores, it is still best to NOT use the syrup. You can read about the research into the glass mold problem that was done by Kathryn Hopkins at the University of Maine. Kathryn is the person who discovered that pouring hot syrup into some sizes of cold glass bottles cause the syrup to cool so fast that there is not enough residual heat in the syrup to kill the mild spores. Thus came the recommendation that when bottling with glass, heat the glass bottles to 200 degrees before adding the syrup.

Joe

[BSD]

were the mason jars new or previously used?

[wobbletop]

We boil the mason jars just before filling with syrup.