I've just sampled my first elderberry wine. 250g of dried elderberries, two litres of Welch's purple grape juice and 1kg caster sugar. It went from 1.106 to 0.992. could that be 15%? It's dark red, plummy and rich. I've already got the next one fermenting, only this time I'm using Tesco Forest Fruit juice which has apples, grapes, strawberries, blackberries and blackcurrants. OG was 1.106. Maybe I will use less sugar next time!