I tried a peach jam recipe that is cooked then cooled to thicken without pectin (6+ hour cool time). The recipe says you can freeze it or can it. What would be the safest method to can it? I have always used the water bath method while the jam was still hot. Would you put the cooled jam in sanitized jars, seal and band them, then place in a 'cool' water bath bringing it up to boiling? Would you then process for 10 minutes like usual? BTW...the jam is the perfect consistency. Would heating it change that? Thanks!
Welcome to SA! While theoretically you could can the jam using some kind of very-slow-heating of the jars in a water bath, in practice I can't find any canning authority who thinks that's a good idea.– FuzzyChefJun 7, 2021 at 16:59
Yes, you may can it, but you will need to bring it to a boil again.
From The University of Georgia for the National Center for Home Food Preservation
Because we are interested in recommending jam and jelly making procedures that offer the highest quality, the least health and safety risks, and the lowest chance of losing product, all Extension recommendations for jams and jellies include a boiling water canning process for room temperature storage of sealed jars. Standard canning jars used with self-sealing lids and ring bands, pre-sterilization of clean canning jars, hot filling of product into the jars, and processing for 5 minutes in a boiling water canner are recommended for highest quality and to prevent mold growth.
The consistency may change, but I don't think it would be drastically different.