What is the better yeast for berry wines? 71B or D-47?
A better question is "why do you prefer the yeast you recommend?", as that will help you understand the qualities of each, which helps you make your decision.
The following is from the
Yeast Strains Chart on WineMakerMag:
71B: A semi-dry white wine yeast that will enhance fruit flavors and add fruity esters. Can be used with whites, rosés, nouveaus, and concentrates.
D-47: Leaves a wine very full bodied with enhanced mouthfeel. Accentuates varietal character and contributes ripe tropical fruit and citrus notes.
Comments from folks that have used both indicate these descriptions are accurate. If you have enough fruit, make a batch with each, bulk age for 3 to 6 months, then bench test individually and blended together to see what works best.
And to muddy the waters further:
QA23: Portuguese isolate used for production of fresh, fruity, white wines. Will not give structure to a wine, but it excels at focusing the fruit either alone or as part of a blend.
K1-V1116: A vigorous and competitive fermenter that, because of its neutral effect on varietal character, is very well suited to fruit wines as well as wines to be made from grapes.
For dark berries, I'd consider a red wine yeast as well.
RC-212: Ideal for full bodied red wines. Emphasizes fruit and spice notes, accentuates character in red grapes.
Presque Isle has a chart that doesn't include descriptions, but does indicate what wines each yeast is best for, along with temperature range and alcohol tolerance.
There are other charts available on the net -- I found these the most useful and bookmarked them.