i had to read that twice tbh"I found out that 500g ginger , grated gives about 300mls juice, so I should have enough for 3 brews. I will report."
Well my experience is quite different - I don't think you will ever get 3 (23 litre?) GB brews from a mere 500g.
Maybe you are happy with a less intense taste. I want a real ginger bite when I drink home brewed GB.
i think he is substituting the 500gm of fresh ginger with the equivalent juice from the bottle.
the blurb says the bottled stuff is 99.7% ginger juice.
i just put my ginger through the fine julienne blades of a mandoline and give it a bit of a chop up.
no idea how much juice from 500gms.
(but i do know now, and so does SWMBO, that ginger puts a unremovable yellow stain on white plastic LOL)