Process for obtaining naringin from dry plant raw material, and particularly grapefruit

摘要

The process consists of (a) comminuting the dry raw material to 2-3mm size; (b) suspending in aq. medium at 4-5% concn.; (c) adding a mixt. of quicklime and slaked lime as a solid powder; (d) stirring until the mixt. reaches pH 11.7 in 5-10 mins. (e) filtering; (f) neutralising with dil. HCl and stirring slowly to give pH 3.5-4.5; (g) allowing to stand for 24 h. to crystallise the naringine; (h) decanting the mother liquor; (i) collecting the crystals in a wash reactor; (j) washing and pressing in a filter press to release the water content to below 50%; and (k) drying in a tray drying oven by hot air to obtain naringine of 97% purity.