In recent years hardy kiwis, popularly known in Europe as minikiwis, have been gaining economic importance and, thanks to their high resistance to frost, they can be cultivated in Poland and in the most European countries.
The new polish cultivar of hardy kiwifruit BingoPBR (Actinidia purpurea ‘Purpurna Sadova’ × Actinidia arguta) was obtained in the breeding programme conducted at Warsaw University of Life Sciences (WULS-SGGW, Warsaw, Poland). It has dominant characteristics of A. arguta, and its fruit differs from other cultivars on the market, mainly in its intense reddish-pink blush and a pineapple-like flavor. The fruit is cylindrical and clearly flattened at the sides. They reach a good size and an average mass of 8 g (to about 14 g).
The fruiting potential of BingoPBR is lower than that of the popular Ananasnaya cultivar, for this reason the scientists at Warsaw University of Life Sciences have demonstrated that the storage quality of BingoBPR cultivar is better or at least as good as Ananasnaya. Additionally, the scientists have determined the appropriate method of handling the fruit to provide consumers with high-quality fruits and nutraceutical content.
The experiment assessed the effect of the fruit ripeness phase during harvest (7.7 and 9.0 °Brix) and the effect of the storage conditions, i.e., normal atmosphere cold store (0.1% CO2:21% O2) versus controlled atmosphere (1.5% CO2:1.5% O2). The fruit evaluation was focused on changes in the basic color of the peel, firmness, soluble solids content, acidity, as well as the main health-promoting attributes, i.e., antioxidant activity, vitamin C content and total polyphenols.
"The fruits of BingoPBR harvested at SSC 9–10°Brix are characterized by a higher content of soluble solids and lower acidity after storage than the fruits harvested at SSC 7–8°Brix. A significant decrease in fruit firmness occurs during the first 14 days of storage. This process occurs extremely fast especially in the ordinary cold storage and in fruits harvested at the extract content above 9°Brix.
"In conditions of controlled atmosphere fruits of BingoPBR, harvested at 7–8°Brix, can be stored for even more than 8 weeks. Low concentration of O2 in the CA results that the fruits look fresh for a longer time, are more firm, and have a greener peel colour. BingoPBR fruits were characterized by a higher content of vitamin C if harvested at higher soluble solids. During storage the vitamin C content decreases in Ananasnaya fruits, but it was not found in BingoBPR harvested at 9–10°Brix. The polyphenol content during storage does not change or slightly decreases, reflecting the greater stability of polyphenols in fruits," the scientists explained.
Source: Ewa Szpadzik, Ewa Zaraś-Januszkiewicz, Tomasz Krupa, 'Storage Quality Characteristic of Two Minikiwi Fruit (Actinidia arguta (Siebold & Zucc.) Planch. ex Miq.) Cultivars: ‘Ananasnaya’ and ‘Bingo’ — A New One Selected in Poland', 2021, Agronomy, Vol. 11(1), 134