Ok, I've been meaning to post back about my experiments on this beer. I made 8 gallons, split into 4 fermentors, with WLP001, WLP320, WLP400 (belgian wit), and WY1010 (american wheat). I added 3 cups of fresh pureed watermelon to each 2.5 gallon batch, 7 days after primary. All batches finished about 1.008.
We had a tasting party a few weeks back....some quick notes:
001: Best watermelon aroma, nice and clean fruit aroma and flavor. Prominent watermelon. Very clean fruit wheat beer, almost jolly rancher like flavor.
320: More flavorful than the 001, nice play of hefe yeast and watermelon flavor. Less watermelon aroma, but great pinkish color.
400: really great mouthfeel, but we felt the spiciness from the yeast did not play as well with the melon.
1010: SOmething amiss here. I get an asprin off flavor. Never had that issue with this yeast before.
And the overall winner was the 320 batch. The way the yeast flavor melds with the melon was really great and complimentary. The 001 was second best - I just had it in a beer tasting over the weekend, and everyone loved this beer.
I'll be making more of this for a wedding next summer, using the 320 for sure. I think the low FG of my beers really helped accentuate the melon flavor, and really helped the drinkability. Next time I might reduce the OG a few points, as these beers finished about 5.5%.