Test the method described in the book <<Sushi God>>
Scrape the ginger and slice it into thin slices
Spread the ginger on the hedge and heat it with hot water. Squeeze the ginger into the water by hand to remove the spicy taste.
Put the ginger in a sweet and sour mixture and bring to a boil.
The ginger pieces are marinated in cool sweet vinegar, and the ginger pieces will have a light pink color. Probably marinated for half a day