Changes in fruit quality, phenolic compounds, and antioxidant activity of kiwifruit (Actinidia eriantha) during on-vine ripening

Kiwifruit is a unique berry fruit which is rich in various nutrients and antioxidant substances. As a typical climacteric fruit, the after-ripening of kiwifruit is accompanied by a rapid decline in fruit firmness, which greatly shortens the shelf life. Here, a new storage method, on-vine ripening, was used to investigate the changes in fruit quality and antioxidant activity of a new kiwifruit cultivar, Actinidia eriantha 'Ganlv 1'. The results indicated that a delayed harvesting of 14–21 days (for transportation) or 35–42 days (for ready-to-eat) was suitable for A. eriantha 'Ganlv 1' fruit, which also improves fruit quality. Additionally, ten phenolic compounds were identified to be the main components of total phenols in fruit of 'Ganlv 1'. Furthermore, gallic acid, chlorogenic acid, epicatechin, and rutin were proved as the major contributors to the antioxidant activity of 'Ganlv 1' fruit, as they possessed strong FRAP and capacities to scavenge DPPH·,·OH or O2−·. Besides, AsA exhibited strong capacity to scavenge ·OH and O2−·. This study confirmed that on-vine ripening is a convenient and economical storage method for fruits of A. eriantha for the first time, and it revealed that the related natural phenolic compounds are important antioxidants.