An objective of the present invention is to provide a taste-improving agent, which does not interfere with the salty taste of potassium-containing food and beverages, and suppress unpleasant tastes such as acridity, pungency and bitterness caused by potassium. The taste-improving agent of potassium-containing food and beverages is characterized by including a lactic acid-fermented yeast extract which is obtained by using lactic acid bacteria to ferment a yeast extract, and containing 7.5 (w/w)% or more of lactic acid relative to the solid content of the yeast extract.本發明提供一種呈味改善劑，係無阻礙含鉀飲食品所持有的鹽味，且抑制鉀所具有的澀味、刺激味及苦味等令人不愉快的味道。本發明之含鉀飲食品的呈味改善劑，其特徵係：含有使酵母萃取物經乳酸菌發酵而得的每單位酵母萃取物固形分包含7.5(w/w)%以上乳酸之乳酸發酵酵母萃取物。
