Crab Salad with Grapefruit

With a live crab: Cook for 25 minutes in salted boiling water, then allow to cool. Remove the claws and crack them carefully, without crushing them, with the back of a heavy knife. Extract the flesh. Open the body and discard the inedible parts. Pick out all the meat, and remove any little membranes or pieces of shell. Set aside on a plate.

With tinn