32 minutes ago, KennethT said:@Duvel I have very little biology knowledge (aka squishy stuff) so I was wondering - is it even possible for mold to grow on a piece of dried kombu? I always thought that mold needed a certain amount of water to grow, but the dried kombu I have is like thin slices of wood and really brittle which makes me think that the water activity is very low.
Unlikely. Lack of moisture and salt content (especially on the surface) will not allow mold to grow. If moisture would be present, I would expect the natural sugars in the seeweed to allow fungal growth. Commercial packs of kombu will carry usually a desiccant to reduce moisture within the packaging even further, but I bought two packs of kombu last year during our Japan trip and none had desiccant of vacuum packaging. And none had mold. They had マンニット, though 😎
