I blended up some skinned ginger and squeezed the juice out of it via a meshed strainer with small holes (I only wanted the juice and I was collecting the pulp for cooking). I collected the juice (200 ml) in a steel vessel, where it remained for over 1 hour. Then I poured it into the lime I squeezed for a lemonade. Later on washing the dish I found a white sediment, I use sediment that instead of residue (ginger fiber) as that was thick white coating on the bottom of plate and I had to use the sponge to wash it away.
Even though the ginger juice was yellow-greenish, this was "salt like" white.
What is that white thing?
PS: I am very sure that it was not there before and I cleaned all the vessels & skinned ginger very well.