Compositional Changes in the Developing ‘Hayward’ Kiwi Fruit in California1

Abstract

Abstract ‘Hayward’ kiwi fruit (Actinidia chinensis Planch.) samples collected at 20-day intervals after full bloom, May 18, until harvest in late October, were analyzed for carbohydrates, protein, organic acids including ascorbic and dehydroascorbic acids, tannins and polyphenolic substances, and cytokinin-like compounds. Starch is a predominant carbohydrate stored in the carpellary tissue which becomes hydrolyzed as the fruit approach maturity. Quinic acid was the main organic acid in young fruit which disappeared concurrently with the appearance of ascorbic acid. Mature fruit has low concentrations of tannins and polyphenolic substances but many raphides. Types of cytokinins changed as the fruit developed.