For jam we need here is Gelfix.

Berries wash, cut into pieces. Mix contents of packet with 1 tablespoon of fructose, add the berries, stir, put on fire and bring to a boil, stirring constantly. Add the remaining fructose, stir again, again bring to a boil and cook for 3 minutes. Remove the foam and pour into dry clean jars, close, flip the jars upside down and leave for 5 minutes. I did like this jam and cherries, and apricots, and blueberries and raspberries (blueberries and raspberries just stretched a bit). It turns out very tasty, especially with cherries! Fructose, of course, also the product is not cheap (a hundred rubles for 0,5 kg), but if you look at how much diabetic jams... the Benefit is obvious!