I'd use blackberry because raspberries are hollow in the center (the fruit wraps around a torus) and they're less similar to boysenberries.

I use 1 kilo/2 1/4 lbs. of boysens to 800g/3 3/4 cups of sugar. 1/4 cup lemon juice plus seeds and pulp in a muslin bag.

I macerate the cleaned berries in the sugar and lemon juice with the bag of seeds and pulp. If I have time I gently simmer the mixture until the sugar is dissolved (with the lemon bag) then cool and refrigerate overnight. (Cover with a cloth not a lid to avoid condensation dripping in.)

If I don't have time I just put the berries and sugar with the lemon juice and bag stirred together in the fridge and let rest overnight. Simmer gently the next day until sugar is dissolved.

Either way, the next day once sugar is fully dissolved, bring to a boil and cook to the jell point. Remove the bag. Stir in 1 T. of Cointreau (optional).

BWB 10 minutes as per usual.

Boysenberry syrup is just the berry syrup recipe. A search on this forum should bring several discussions of fruit syrups up. If you can't find them just ask and one of us will locate the threads.

Carol

Thanks Carol. I am eagerly brooding over my boysenberry patch--I think they will ripen in about 1 week or less.

One question about the boysenberry syrup: has anybody ever had trouble with the syrup jelling unexpectedly? Linda Z warns about that in her book.

Yes, though in my case it happened with strawberry syrup, not boysenberry. So yes, it can happen, and boysenberries would be even more problematic than strawberries, as they have more natural pectin.

That is less likely with fully ripened as opposed to partially underripe fruit.

The nearer you get to that 220 degree mark, the greater the likelihood, so stick to 218-219 for syrup. (Assuming an accurate thermometer.) If you're at altitude, jell point is 8 degrees above boiling, whatever your boiling temp is and syrup would be 1-2 degrees lower than that.

Carol

P.S. I should have mentioned that if it turns to jelly, jelly also has its delights and could be returned to syrup by restoring some of the water. Just stir a warm tablespoon or so into the jar, whatever amount results in the desired pourability.

Carol