Bloodberries are an indigenous type of berry found on Irk. Bloodberry juice was a popular nonalcoholic beverage among the Irkens, best served warm to near-cold. As with many Irken foods and beverages, it is prepared the same way as Earth beverages.
Bloodberries get their name from the color of the juice itself—it is scarlet, the color of human blood.
Upon establishment of contact with the Tallest's flagship to the starship Magnus, Zee suggested to her brother ZIM the service of bloodberry juice and iced tea during a dinner which the Magnus crew was hosting for him and his party.
Captain William Spalding was able to procure some for his crew as well, and served it at the state dinner with ZIM. When told by one of his crewmembers on how delicious it was, he wryly noted it was, "one of the advantages of being a thousand light years from Conglomerate headquarters", as some members didn't know about Irken culture.