For a long time after the grapefruit's introduction into the United States (Florida) in the early part of the nineteenth century, grapefruit was considered to be of no particular value. It was grown merely as a curiosity: during the latter part of the maturing season. The ground under the trees was covered with fruit which was allowed to rot where it lay. Gradually, the residents began to recognize that the fruit was refreshing and wholesome, and this information was passed on to tourist from the North. The first commercial shipments of grapefruit were from Florida to Philadelphia and New York in 1880. The first shipments are said to have netted the growers only about 50 cents a barrel.
Walton B Sinclair "The Grapefruit".

I would have made lots of grapefruit wine if they're still 50 cents a barrel! Good info on US Grapefruit history Millet!

Grapefruit wine... Now that would be very interesting.

THE GRAPEFRUIT #2 - The fresh weight of a mature grapefruit consists of 35 to 50 percent juice. 35% in August and 50 percent in December. The juice consists of 88 to 93 percent water, and up to 13 percent soluble solids , mainly sugars and acids (chiefly citric). The specific gravity of the whole fruit gives useful information regarding its quality, because quality depends mainly upon the juice content and the amount of soluble solids, both of which affect specif gravity. It has been found that the specific gravity is greater for the stylar end of the fruit and less for the stem end. Therefore, if your wife cuts a grapefruit in half to serve at breakfast, be sure to take the sweeter blossom end and let her eat the half from the stem end. (The Grapefruit Walter Sinclair)