Segmenting citrus fruits isn’t difficult. Just follow Brian Samuels great step by step guide and you’ll be safe.
By Brian Samuels
Step 1. Cut off both ends of the citrus. Be aware that some citrus has more pith than others, but you want to cut off to the point where there is no more white. 
Step 2. Place the fruit on one flat end and cut off the peel and pith, working your way down lengthwise with the knife.
Step 3. At this point, you will want to work over a bowl. Carefully cut between the membrane on either side of the segment (there are lines designating where the fruit segment is held). This will release the segment and you can let it drop into the bowl. Save all the remaining juices (if you are making a salad, this can be used for the vinaigrette).
If you are looking for a great way to use these grapefruit segments, check out this recipe for Grapefruit Cake.
