Open the oysters. Make sure to keep as much juice in the oyster as possible and ensure no shell pieces are left behind. Keep them cool in the refrigerator, covered with damp kitchen paper.
Sweet: Cut the apple into very fine brunoise. Place a teaspoon of brunoise on the 3 oysters and finish with the parsley leaves and pepper from the mill.
Sour: Crush the red currants in a bowl. Slice the shallot finely and add it. Mix in the juice of 1 lime and 1 tsp of crushed coriander seeds. Finish with pepper from the mill.
Bitter: Remove the skin from the grapefruit as well as possible, and then cut out the segments, leaving only the pink flesh. Place a segment on each oyster, finish with sesame oil and black pepper from the mill.
Salt: Place a teaspoon of salmon roe, a teaspoon of sour cream, a small sprig of sea asparagus on 3 oysters, and finish with pepper from the mill.