pk, it's hard to offer comments when you haven't said anything about how you made your wine (how much fruit per gallon of wine, how much sugar added, which yeast used, etc.). But, having said that, I'll shoot from the hip anyway.
I have made black plum wine two ways. Most of the time I used whole crushed fruit and refined cane sugar. Once I kept the pulp in the wine for a very long time to extract some color for a darker wine. That wine got a little darker (not as much as I wanted), but was a bear to clear. In fact, it never did polish. The last time I made it I tossed 1/2 ounce of dried elderberries in the must and strained them out two days later. It remains the only deep red plum wine I have ever made or even seen.
Plum wine works well with Demerara sugar. This is a light brown sugar with large golden crystals. It is slightly sticky and has an unmatched flavor. It is also difficult to find and expensive, but worth the investment when available. Do NOT use regular brown sugar, although "Sugar in the Raw" is interesting with plum.
I don't think any of the cultivars match the flavor of wild plums. I have tried several wild varieties (actually, they are different species) and every single one of them -- with the exception of Prunus ilicifolia -- made exceptional wine. You might want to see my WineBlog entry for September 11, 2004 at
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Jack Keller, The Winemaking Home Page
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