We recite “Borei Peri HaEtz” (Ktzot HaShulchan Siman 53), because it is considered the “sap” (sweat) of the fruit. For other juices, we recite “Shehakol Nihyah Bidvaro,” even if they contain pieces of fruit, because the pieces are secondary to the juice. This is not the case with the “sap” of the fruit, which has the same status as the fruit itself, and therefore requires the blessing “Borei Peri HaEtz.”