Grapefruit
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The grapefruit is a large citrus fruit that is moderately sour and slightly bitter. It is well-known for causing dangerous interactions with drugs, so be sure to investigate this if you are taking any medication. Pink or red grapefruits tend to be sweeter and have more vitamins than the "white" (yellow) grapefruits.

To serve a grapefruit in the traditional manner, first cut it in half right across the axis. A small spoon may then be used to scoop out the pulp. You may wish to first cut around the center or around the edge, possibly using a bent serrated knife. You may wish to use a grapefruit spoon. If the grapefruit is particularly sour, you might sprinkle some sugar on top.