The present invention is concerned with providing refined plant isolates that can be used as starting materials for the production of functional food ingredients, such as taste enhancers, through an isolation process that employs ion exclusion chromatography. More particularly, the present invention provides a refined plant isolate comprising at least 30% by weight of dry matter of water soluble plant components selected from fructose, glucose, proteinaceous matter of plant origin, acids and potassium, said isolate further being characterized in that at a concentration of 40° Brix the isolate: .contains at least 0.3 wt % of glutamate； .contains at least 500 ppm of K+； .contains less than 300 ppm of Ca2+； .contains less than 700 ppm of Mg .contains less than 1 wt. % of components capable of passing an ultra filtration membrane having a molecular weight cut off of 250 kDa； wherein the concentration ratio ([Ca2+]+[Mg2+])/[K-] does not exceed 5:100, each of said cation concentrations being expressed in ppm.
