The blood orange is a variety of orange (Citrus × sinensis) with crimson, almost blood-colored flesh.
The distinctive dark flesh color is due to the presence of anthocyanins, a family of polyphenol pigments common to many flowers and fruit, but uncommon in citrus fruits.
The blood orange is a natural mutation of the orange, which is itself a hybrid, probably between the pomelo and the tangerin.
The skin can be tougher and harder to peel than that of other oranges. Blood oranges have a unique flavor compared to other oranges, being distinctly raspberry-like in addition to the usual citrus notes
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https://en.wikipedia.org/wiki/Blood_orange
