Do you use fresh ginger? I didn't for a long time for several reasons. One being that I wasn't that fond of the strong taste of the powdered ginger spice and thought that fresh would be even stronger. However I found out that fresh ginger has a more pleasant taste than the powdered. When I started to use the fresh ginger, I became frustrated because I found it hard to grate- even when I used the recommended rasp like the one pictured, it went stringy and I ended up with ginger juice rather than finely grated ginger. I also found that even if I refrigerated it, the ginger would go bad before I had a chance to use it all.
Then I heard about freezing it.