Place toasted seeds, white pepper and salt in spice grinder. Grind to the size of coarse ground pepper. Brush outside of tuna with olive oil. Crust tuna loin with ground spice mixture. Sear tuna in a non-stick pan, using olive oil sparingly, approximately 45 to 60 seconds on all sides. Should be golden brown on the outside and pink in the center. Slice into 1 1/2 to 2-inch pieces and serve with papaya salad. Can be stored in the refrigerator tightly wrapped 3 to 4 hours before serving.