That would make a nice sauce, but even with NOT doubling it, I doubt it would set. Freezing breaks down the pectin, peaches don't have much and with using half as much the raspberries as peaches so they won't help much ((esp. after freezing). Raspeberries aet up OK on their own but I always end up with peach preserves (OK, I do like a loose set so I don't cook them a long time) rather than a thick jam.

It isn't just that it may not set properly; it's that by the time the mixture has been cooked down to the proper set point the preserve has lost a lot of its fresh flavor.

You have basically 7 cups of product in the original recipe (fruit and sugar). Doubling would be 14 cups and 3 1/2 quarts of product is just a lot to deal with.

As mentioned also, both the raspberries and the peaches are on the lower end of natural pectin, so even optimally this will fall naturally on the softer-set end of the spectrum.

Carol

Thank you both. I was hoping to avoid pectin, but I did end up using it. I had a bulk package of pectin with very basic guidelines in it. Wish i would have gotten bulk pectin in the past! it basically said for 2 jars of jam, use 1 2/3 cups of fruit, and 1 to 1 2/3 cups of sugar. So - i was able to come up with a solution to using the odd amounts of fruit i had on hand with a relatively low sugar to fruit ratio. It set great, and turned out awesome :)