Carrageenan is that the carrageenan is first dissolved and filtered to remove cell wall debris. The carrageenan is then precipitated from the clear solution either by isopropanol or by potassium chloride. A hybrid technology in which seaweed is treated heterogeneously as in the semirefined process exists, but alcohol or high salt levels are used to inhibit dissolution. This process is often used on South American seaweeds and gives some of the cost benefits of semirefined processing, while allowing a wider range of seaweeds to be processed, however, the naturally low cellulose levels in some South American seaweeds allow them to be
Purple made with dye from the cochineal insect, became the royal color in Europe. In 1464, Pope Paul II decreed that cardinals should no longer wear Tyrian purple, and instead wear scarlet, from kermes and alum, since the dye from Byzantium was no longer available. Bishops and archbishops, of a lower status than cardinals, were assigned the color purple, but not the rich Tyrian purple. They wore cloth dyed first with the less expensive indigo blue, then overlaid with red made from kermes dye. While purple was worn less frequently by Medieval and Renaissance kings and princes, it was worn by