I'm working on some formulations for a new product using pre-distilled 190pf base spirit, then adding water, sugar, and a few flavor components. I'm using RO water and have confirmed that the flavors are completely water soluble. At some point after blending (typically a few weeks) I've noticed that a white sediment-looking formation collects at the bottom of the bottle. When it is disrupted it "floats" upwards and disperses throughout the bottle, looking similar to rising smoke. When you shake the bottle heavily, it disperses completely but only to return within a day or so.
I've confirmed that the issue is not caused by any type of bacteria, calcium in the water, or other potentially obvious things. I initially thought cold temperature was the driver, but I've tried putting it in the freezer and it doesn't seem to directly cause the issue. Has anyone ever encountered this before, or do you have any insight into what might be causing it and how to eliminate it?