Elucidating mechanisms of internal browning in fully ripe apple fruits by measurements of gas condition in tissue

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K15522
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 39030:Horticultural science-related
• Research Institution: Tokyo University of Agriculture
• Principal Investigator: YOSHIDA Mika 東京農業大学, 農学部, 助教 (50825403)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 内部褐変 / リンゴ / 収穫日 / 貯蔵温度 / 組織内ガス / ガス透過性 / エチレン

Outline of Final Research Achievements

Internal browning may occur in apples after long-term storage. Since internal browning is caused by an oxidation reaction, the oxygen concentration in the tissue is also thought to have a strong influence on the reaction. However, it has been difficult to measure the actual oxygen concentration in tissues with the various instruments currently available. Therefore, an attempt was made to create a new measurement device by modifying an optical oxygen sensor using an unprecedented measurement system.
By creating a device for measuring gas in tissue and gas permeability, we succeeded in measuring gas in tissue and gas permeability in apple fruit, which had not been possible to examine before. It was suggested that oxygen permeability in the early stages of storage may play a role in the occurrence of browning after 6 months of storage.

Free Research Field

青果物の収穫後生理

Academic Significance and Societal Importance of the Research Achievements

リンゴの内部褐変の発生メカニズムには収穫日、貯蔵条件などが関与しているが、未だ不明な点が多く、その研究においては半年を超える長期貯蔵試験が必要であった。しかし、本研究で新たに作成したガス透過性測定装置を使用したことで、貯蔵開始直後の果実サンプルの酸素透過性と内部褐変発生の間に負の相関関係が認められた。本研究では、果実のガス透過性を調査することで、貯蔵後の褐変発生を予測できる可能性を見出した。本研究の成果は、内部褐変発生のメカニズム解明と、予測・抑制技術の開発に貢献するものと考える。