Blood oranges earned that name because of the vivid red color of their flesh. The fruit is similar in taste and texture to a regular orange, but unlike traditional oranges, blood oranges aren't available year round. That's because they rely on certain kinds of weather to develop their red color.
The Moro variety is available from December through March. Blood oranges are readily available during these winter and spring months because the climate where the fruit trees grow plays a role in the formation of the red hue.
The red color of blood oranges is due to the presence of anthocyanins, which are compounds that give many other fruits and vegetables their red, blue or purple colors, as well. Harvesting blood oranges at the peak of freshness ensures the maximum amount of anthocyanins in the fruit. Waiting until the winter and spring ensures that the blood oranges will be as vividly hued as possible, and the darker the color, the more anthocyanins the fruit contains. Anthocyanins might help prevent cancer and heart disease, as well as treat eye disorders.