Go for it! I've not used persimmons before, but I've made 2 batches of fruit Hefeweissen. One was kiwi, the other blackberry. I use a Franziskaner clone because of the slight sweetness and banana, and add the fruit at flameout then let it sit for ten minutes. The kiwi version is one of my friends' absolute favorite. The blackberry is a bit tart, but I like it a lot.
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