Frozen berry jam question

moderne.ms, May 7, 10:12pm
I was lucky enough to buy a quantity of mixed frozen berries quite cheaply, and would like to make jam. I remmeber reading, I think it was on here, about how you can add yellow plum to the berries, which of course makes the berries go further, but also helps the jam set. Can anyone help me out with confirming this, and quantities? Thanks.

harrislucinda, May 7, 11:43pm
neverheardofthatbutremembernot toaddso much waterasthey arefrozen

moderne.ms, May 8, 12:12am
yeah, I've used frozen berries so know they end up looking very sad when defrosted! ! ! The plum use interested me from the view of making a smaller amount of berries go further... ... ... . .

cgvl, Apr 13, 2:01am
Frozen berries are fine but don't add water to them. Use from frozen.
I add 1stalk of finely chopped rhubarb per kg of fruit, cook with fruit/berries. It dissolves into the fruit mix and isn't able to be tasted. Also add the juice of 1lemon per kg of fruit. Both of these help to set the jam, without the need for the jam setting expensive sugar or pectin/jam setting mix.
I've never added plums to berrie but have made yellow plum and pineapple jam which is really nice and one I prefer over red plum.