Think about this. Water can be stored in a container at room temperature and unrefrigerated. Kava powder can be stored in a container at room temperature and unrefrigerated. But mix those 2 things together, with no other ingredients at all, and now suddenly that combination means it must now be refrigerated to prevent spoilage. This has totally wrecked a culinary philosophy I have been living by, for years, that I came up with by just using simple logic. If Substance A does not require refrigeration and Substance B does not require refrigeration, and I mix those 2 together, I have always concluded it's safe that the combination does not require refrigeration. So now that I discover that's not the case with kava root powder combined with water, then I wonder how many other things my rule does not apply to ?