So since these recipes need a cup of juice, I decided to make my blackberry-peach jam with the pineapple juice, also added a little agave. Very delicious!! I need to make a second batch of this one. I ran out of the little jelly jars I just bought so went to my 1/2 pints.
I guess I have a couple batches with the blackberries-but we love these, and I don't need to freeze any this year, cause I still have enough in there from last year.