I haven't tried to use it yet, doubt it's good. It had moisture, I threw the sacs in without removing the pollen.. the flour I've seen a few times online, it dries it up apparently.
Was just curious. Seems to make sense if it absorbs moisture, but doesn't cause a bad reaction to the pollen.
Did a google search and seen that some also used flour. It's probably pointless though when an actual silica gel desiccant is used.
The issue with freezing is that water will turn into ice at very low temperatures in the freezer and a desiccant can't soak up ice from what I read, only water in it's natural form.
So even if you put a desiccant in a jar w/ the pollen, it will be less effective once that water turns into ice from the sounds of it.
Silica gel works at below freezing temps, but works best at room temps.
Also, it seems water is used on plants that have been pollinated only to immobilize it so it can't spread to other plants. I haven't read anything that factually asserts that water deactivates the pollen by killing the pollen. It's touted that it can by some, but I haven't seen science on it.
So either way, just place the pollen in a jar or vial w/ a desiccant, then into the freezer and you should be good for years from the sounds of it.