Fraktsioon tähistab komponentide kogumit ühe tunnuse baasil - nad ei seebistu leelise toimel (ei moodusta seebitaolisi ühendeid, s.t rasvhapete sooli).
The butter or concentrated butter is saponified with potassium hydroxide in ethanolic solution and the unsaponifiables are extracted with diethyl ether.
The oil, with added α-cholestanol as an internal standard, is saponified with potassium hydroxide in ethanolic solution and the unsaponifiable matter is then extracted with ethyl ether.
