I would advise not doing it on the ship. I had my teeth whitened at my dentist ($$$, but loved it). For 24 hours you cannot eat ANYTHING with color. Not even a crust of bread. Forget about Palo souffle, steak, watermelon, nada. I ate turkey with mayo on bread with the crusts off and water for 24 hours.
But Oral B white strips. It's what I use to keep my teeth white. That and drink colored drinks through a straw.
Also your teeth might be sensitive afterwards.