A method for producing a yeast extract with a high copper content, said method being characterized by compirising an extraction step for suspending a copper-containing yeast in a solution containing a carboxylic acid and/or a carboxylic acid salt and then separating the solid component of the obtained suspension from the liquid component； a yeast extract with a high copper content； and an agent for maintaining and restoring the green color of foods and vegetables.本發明係提供一種含有高量銅之酵母萃取物之製造方法，其包含萃取步驟，係使含有銅之酵母懸浮於含有羧酸及羧酸鹽之至少任一者的溶液中，並將所獲得的懸浮液之固體成分與液體成分加以分離；並提供一種含有高量銅之酵母萃取物、食品及蔬菜之綠色保持復元劑。
