The best for pickling are the tender "stem ginger" pieces, generally available about midsummer in areas where there are large Asian populations. This has barely any skin, as it is still in the baby stage and has a faint tinge of pink where the stems have been trimmed. In lieu of the baby ginger, you may use the older rhizomes, but please make sure that it is very fresh and that no withering or molding is evident.
This recipe is from the book, Fancy Pantry...one of my very favorite books of doodads...<g> 1 pound tender young ginger or twice as much older stemmed 1 1/2 T pickling salt 1 1/2 c rice vinegar or distilled white vinegar 3/8 c water 3/8 c sugar 1. To prepare young ginger: break the pieces at the joints and trim off any discolored or withered pieces. Scrape off the skin with a sharp knife. Wash pieces and pat dry.
2. To prepare more mature ginger, peel using a hand-held bladed peeler, then peel the tender outer layers using the peeler. Move to another section when you encounter the pulpy center of the rhizome.
3. Combine the ginger and salt in ceramic or stainless steel bowl, turning the pieces to coat with salt. Cover and set aside for 24 hours, turning the pieces a few times in that period.
4. Drain the ginger and discard the liquid. Dry the ginger thoroughly and place in a clean quart jar or two pint jars (canning jars are not necessary).
5. Stir together vinegar, water and sugar until sugar is dissolved, then pour over ginger pieces, covering by at least 1/2 inch. Cover with a lid, label and refrigerate. Ready to eat in a week...slice off thin pieces with the swivel bladed peeler.