how can I ferment wheatgrass sprout i.e., rejuvelac is puportedly fermented naturally, but I think not.
Can I just puree the sprouts, then add 1/3 cane sugar, and let it ferment ( maybe some wine yeast to accelerate the process), ideas please??
I have never fermented them, but I will give you my two cents.
I believe that they are fermentable without pureeing them. I wouldn't add sugar. It's not healthy. All vegetables have some of the residual stuff that will turn into fermentation. If I were to add something, it would be some cabbage, or perhaps some starter from a previous ferment. You don't have to add much to get it going. It would probably work anyway, but your odds are increased and your anxiety/chance of having to throw it out is dramatically decreased.
Adding sugar will encourage yeast to grow, which may be what you want if you are seeking carbonated or alcoholic drink. There may also be a lot of natural sugars in the sprouted grain already.
You could malt the sprouts and use them in ferments like beer, small beer, sourdough.
Wild fermentation by Katz is a great read for this kind of fermentation experiment. I think Sally Fallon has some sprouted grain ferments in her book Nourishing Traditions. Most of Fallon's recipes use whey (live, as in from a fermented source like labneh, not from cooked cheese making) as a starter.