The blood orange is a variety of
orange (Citrus sinensis) with crimson,
blood-colored flesh. The
fruit is smaller than an average orange; its skin is usually pitted, but can be smooth. The distinctive dark flesh color is due to the presence of
anthocyanin, a pigment common to many flowers and fruit, but uncommon in citrus fruits. Sometimes there is dark coloring on the exterior of the rind as well, depending on the variety of blood orange. The reason for the unusual internal color is related to light, temperature and variety.
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