Hi! I recently processed 6 jars of blueberry jam. I chose a pectin free recipe that required I low boil the jam for 20 minutes, followed by water processing. The end result was very thick! I also wish I reduced the sugar, but it is ok. Is it possible that I empty the jars into a pan to melt and thin the jam with a little water, and then process again? I typically give preserves as gifts and I hope I can make this gift worthy. Thank you!
My suggestion would be to open one jar and put into a microwave safe container and heat in microwave to dissolve the jam. Then you can add a little blue berry juice or water to thin it and see if it will set back up. If that works you can do the same with the other jars. If it will set up you can safely reprocess.
Reprocessing jam high in sugar is not a safety issue but sometimes the pectin will be broken down and you will end up with a syrup or if the jam is really thick it will be tough and not melt down. Just experiment a little and see what happens.
If you have other food preservation questions you might like to call the OSU Food Preservation/safety Hotline which is not open M-F from 9 am-4 pm and staffed by certified Master Food Preservers. The number is 1-800-354-7319.
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