I think I got the idea from morwen and goodhealthgourmet -- dehydrate slices of tangerine (used clementines and blood oranges) and then pulverize the crispy slices to make a lovely dust for sprinkling and to give as gifts. So, exactly as advertized my tangerine dust is beautiful and very tasty but it is clumping. Those slices were really crispy (took MUCH longer than 3 hours in the dehydrator) and I pulverized them fresh out of the dehydrator so despite what my skin says, it must be the ambient moisture in the air around here. Only thing I can think of is to add a few grains of rice to each bottle I make up. Any other thoughts?