[Challenge] It is possible to provide a beverage or extract to contain high concentration in the form of an easy to drink - 2,5-piperazine-dione, 3,6-bis (phenyl methyl) is a useful substance having a learning motivation improvement action -, (3S, 6S) . [MEANS FOR SOLVING PROBLEMS] Ratio of Brix (Bx) is 6 (μg / 100g) / Bx and above: content (μg / 100g units) - 2,5-piperazine-dione, 3,6-bis (phenylmethyl) -, (3S, 6S) beverage or extract, texture and flavor is good, and appearance may also be further. In addition, as a useful food and drink to improve motivation for learning, continued intake of long-term is possible. None [Selection Figure]【課題】学習意欲改善作用を有する有用物質である2,5-ピペラジンジオン,3,6-ビス(フェニルメチル)-,(3S,6S)-を飲みやすい形で高濃度含有するエキス又は飲料を提供すること。【解決手段】2,5-ピペラジンジオン,3,6-ビス(フェニルメチル)-,(3S,6S)-含有量(単位:μg/100g)とブリックス(Bx)の比が6(μg/100g)/Bx以上のエキスまたは飲料は、香味や舌触りがよく、さらに外観もよい。また、学習意欲の改善に有用な飲食品として、長期の継続摂取が可能である。【選択図】なし
