Naringin is the dominant flavonoid bitter principle in grapefruit juice. The aim of this work was the modeling of the enzymatic hydrolysis of naringin, with naringinase immobilised in Ca-alginate beads, under high pressure, in order to optimize this technique for removal of the bitter taste from juices, using response surface methodology (RSM). A central composite rotatable design (CCRD) was employed involving two variables (pressure and temperature) at five levels (