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

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.

Influence of Within-canopy Shading on Fruit Size, Shoot Growth, and Return Bloom in Kiwifruit

“…3) and reached maximum concentrations in fruit from both shoot groups by 18 Sept. Fruit from the 2 groups did not differ significantly in starch or alcohol-soluble sugar concentrations on any sampling date. The late season decline in starch levels and concurrent increase in alcohol-soluble sugars are attributed to starch hydrolysis during fruit ripening (8). Fruit harvested 12 Oct. from exposed shoots had a slightly higher mean starch concentration, before and after ripening, than those from shaded shoots, but sugars levels in the 2 fruit groups were not significantly different (Table 1).…”

Qualidade de puré de kiwi armazenado sob vácuo

“…De entre os constituintes do kiwi, destaca-se a vitamina C cujo teor é extremamente elevado, excedendo 150% da dose diária recomendada (DDR) por cada 100 g de fruto. A variedade Hayward contém, normalmente, entre 65 mg (Nishiyama et al, 2004) e 80 mg (Okuse, 1981;Visser et al, 1983) por 100 g de fruto, com algumas excepções: 107 mg ácido L-ascórbico/ 100 g kiwi (Castaldo et al, 1992). Este teor de vitamina C confere ao kiwi um potencial antioxidante enorme, sendo, assim, um fruto muito bom para a saúde humana, em geral.…”