Study on the food function of insoluble polyphenols in fruit and the processing condition that accelerates their formation

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K05906
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 38050:Food sciences-related
• Research Institution: Shinshu University
• Principal Investigator: Hamauzu Yasunori 信州大学, 学術研究院農学系, 教授 (90283241)
• Co-Investigator(Kenkyū-buntansha): 荻田 佑 信州大学, 学術研究院農学系, 助教 (50738010)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 果実 / 不溶性タンニン / プロアントシアニジン / 胆汁酸吸着 / 加工条件 / 細胞壁繊維

Outline of Final Research Achievements

Processing of proanthocyanidin (PA)-rich fruits sometimes cause insolubilization of PAs, in other words, the formation of non-extractable PAs (NEPAs). In this study, superiority of NEPAs as a food components and the NEPA forming conditions during processing are investigated. Strong bile acid-excretion effect has been shown in the mice fed NEPA fraction prepared from dried persimmons. Potential health benefit to the intestinal environment of NEPA-fed mice was also suggested. The NEPA formation in fruit was observed by drying, boiling, homogenization, cooking, or freezing. In case of drying of quince pieces, drying with 60°C cause a large NEPA formation. While association of Chinese quince PA to the fiber components in a suspending solution was accelerated under the high temperature and low pH condition.

Free Research Field

園芸利用学

Academic Significance and Societal Importance of the Research Achievements

本研究の意義は，果実の加工時に形成される非抽出性プロアントシアニジン（NEPA）が食品成分として何らかの有益性を持つかという点を，特に胆汁酸排泄促進作用に焦点を当てて確認した部分が大きい。また，果実加工の際，通常の分析法で定量されるプロアントシアニジンが減少したように見えても実際はNEPAの形で存在する場合があることを示し，このことは，成分分析により品質評価を行う際の新たな留意点を提示するものとなっている。さらに，本研究は，果汁飲料などの調製時にPA含量を高く維持する条件を考える基礎的情報を提示したことにも意義がある。