Biochemical composition of fruit in <i>Actinidia deliciosa</i> (A. Chev.) C. F. Liang & A. R. Ferguson in the humid subtropics of Russia

Abstract

The article characterizes a kiwifruit cultivated in the subtropical zone of the Black Sea coast in Krasnodar Krai. Scientists are currently interested in kiwifruits that contain a considerable amount of vitamins, specifically vitamin C. The present study aims to examine the biochemical composition of a kiwifruit having a high nutritional value, as well as vitamins and useful elements necessary for the human body. These studies on the plantings of Actinidia deliciosa have been conducted at the Adler Experiment Station of the Federal Research Center N. I. Vavilov AllRussian Institute of Plant Genetic Resources (Krasnodar Krai) since 2017. The growing area is 5×4 m, amounting to ha. The crop is grown in alluvial grassland low-humus soil. The biochemical composition of fruit was analyzed at the Department of Plant Physiology and Biochemistry of the Subtropical Scientific Centre of the Russian Academy of Sciences. The results of biochemical studies (2017–2018) evaluating the fruit of Actinidia delicata are presented. The study included five kiwifruit varieties: ‘Hayward’ (late ripening period), ‘Allison’, ‘Abbott’ (early ripening period), ‘Bruno’, and ‘Monty’ (average ripening period). The maximum sugar amount of 9.67–10.92 % was observed in the fruit of ‘Monty’, ‘Bruno’, ‘Abbott’, and ‘Allison’ varieties, while the minimum amount was found in ‘Hayward’ (7.79 %). In the experiment, the titratable acidity amounted to 0.75–0.82 %. The sugar-acid ratio was found to be within the range of 9.50–14.99 RU. The best varieties in terms of the content of extractive substances in fruits were ‘Abbott’ and ‘Bruno’. A high ascorbic acid content of 148–171 mg/100 g was observed in ‘Hayward’, ‘Abbott’, and ‘Bruno’ varieties, while a low content of 119.50–125.50 mg/100 g was noted in ‘Monty’ and ‘Allison’ as compared to other varieties. The quantitative content of dry matter was found to be within 15.04–16.00 %, which indicates good transportability, storability, and shelf life of kiwifruit as long as the necessary rules are followed.