I'm using the ginger to flavor some Kombucha ( fermented sweet tea ). I'm only drying it to modify the flavor profile, I've found using fresh ginger creates a lemony flavor that I don't really want. So drying it first seems to eliminate that lemony flavor and rather than kombucha that tastes like lemon ginger, I get kombucha that tastes very similar to a great ginger ale.
If I was going to store it... I'd vacuum seal it..