Pink Ginger from Sushi Restaurants.

When going to sushi restaurants, many types of sushi come with some delicious slices of pink ginger in a little bowl. From my experience, most ginger is yellow, and doesn't taste quite the same as this pink ginger. What do they do to this ginger to make it pink?

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or better yet, Lurk in ethnic markets

It's young ginger, selected for its lack of spiciness. The pinkness is a natural result of the pickling process (rice vinegar, salt, sugar), although some commercially produced ones add food colouring.