I dragged the bamboo for my battens out of the shed yesterday and washed them down with water and bleach to get the mould off. They didn't look wonderful. So I figured I'd try an idea I had read about and had done once before. The idea is to heat up the surface layer till it sweats, this sweat is then wiped off with a rag. I used a gas blowtorch. Don't heat up too much at a time and if there is a whitish residue then apply the heat again and repeat the process. The difference it makes is quite a lot, it looks like it has been polished. I might write something up but here's a link to some photos Post #911
http://forum.woodenboat.com/showthread.php?88318-Redwing-update&p=3275669#post3275669