small batch berry jam help

Greetings all!
I have 6 cup of juice and pulp from wineberries and blackberries.  I have Ball Real Fruit Classic Pectin on hand and of course I have sugar.  Does anyone have suggestions for how much pectin and/or sugar I should use for jam.  I've done several internet searches and have almost drowned in the differing information.

We do equal parts berry slush to sugar and no additional pectin. That produces a very sweet jam, but when we've backed the sugar off, the texture got wonky.

Thank you!  Just what I needed: straightforward advice backed by experience.

Oh, it just occurred to me -- we use turbinado sugar (sugar in the raw) rather than white sugar. I'm sure that adds flavor, but I'm not sure if the chemistry of the jam is changed between the two.

I agree with Christopher on the sugar proportions for a jam that will set and keep - although I do 1lb (UK) sugar per pint (UK) of cooked fruit.
For a fruit that is low in pectin (and I suspect most berry fruit is) I often add apple pulp to provide pectin. I find you can add quite a high proportion without detrimentally affecting the flavour or colour. Lemon juice often can help a low pectin fruit set better too and cut through the sweetness a bit.

I have never used pectin. My ratio like the others is 50-50. I just made Dolgo crabapple/cranberry jelly, very nice.

Nancy Reading wrote:I agree with Christopher on the sugar proportions for a jam that will set and keep - although I do 1lb (UK) sugar per pint (UK) of cooked fruit.
For a fruit that is low in pectin (and I suspect most berry fruit is) I often add apple pulp to provide pectin. I find you can add quite a high proportion without detrimentally affecting the flavour or colour. Lemon juice often can help a low pectin fruit set better too and cut through the sweetness a bit.

Thanks for reminding me: I realized the apple thing this year when I made apple syrup with apple peelings.  I did add 3 small apples to the berries.

I make lots of jam with much less than 50-50 sugar. I add sugar after the fruit is hot and simmering, only just enough sugar to make it tasty, and a little more because it tastes sweeter while hot. I don't worry about it "setting," I just enjoy it with lumps of fruit in a runny sort of sauce. Intensely delicious, much tastier than 50-50 jam. I guess it's really preserves, not jam.

I've been doing this every year for about 20 years and it keeps for a year or two on the shelf just fine. I only do this with fruits that have natural acidity to them, otherwise add lemon juice: but your berries should have enough acidity on their own. Make sure to water bath the jars after closing them, like 10 minutes if the contents were filled hot, or 20+ minutes if they were filled lukewarm. It is the acidity and the water-bathing that preserve it, not the sugar, since I don't use 50-50 sugar.

Oh, and by the way I've never had a jar lifter, I just use rubber gloves: either the thick insulated ones or thin dishwashing gloves with thin winter gloves inside.