From our Ask the Chef series.
Q: If you put a frozen turkey in a brine (warmed brine, even?) could it thaw faster?
A: No, thawing a turkey in brine is not recommended. For reasons of food safety, brine must always be chilled before using. For best results, brining should only be used with a thawed turkey--otherwise, you risk uneven brining.
Brine must always be chilled before using for food safety and brining a frozen turkey will result in uneven brining. Not recommended.
Subject: FW: Frozen Turkey