Influenсe of Seasonal Factor on the Chemical Composition of Persimmon

Abstract

Persimmon is one of the most popular and favorite fruits not only in Georgia, but also in other countries. People love it for its unique specific taste and high nutritional value. There are more than 500 types of persimmon, properties and tastes which depend on the persimmon growing conditions. The purpose of this project was to study the persimmon fruit chemical composition, the regularity in the quantity changes of the bioactive substances and technical-economical persimmon parameters during its storage and technological processing; to develop a highly profitable and efficient composite production technology for a new assortment of products and high quality beverages. Organoleptic and chemical tests of 12 persimmon fruit varieties were made. The content and composition of sugars, polyphenols, pectin, and tanning substances, were defined; and the relation of these parameters to the fruit maturity degree, the dynamics of their change in the ripening and storage process were determined. In addition, we determined the content of sugars ( inverted, total, saccharose), tanning substances (free, total), polyphenols and nitrogen through a spectrophotometric method, dry solids through a refractometric method, pectin (total, soluble, protopectin) and acidity through a potentiometric method, and cellulose through a chlorite method. The feasibility of the persimmon fruit industrial processing was established. Persimmon fruit of Khachia and Khiakume varieties were proved to be the best raw material for the industrial production of a fruit alcohol and beverages. It should be noted here that persimmon fruit must be harvested in November when they have a dark orange colouring and their dry solids content reaches 18%, inverted sugars make up 16-16.5%, and the acidity is 0.12%. For concentrate production, persimmon must be harvested in October when the fruit are yellow and their tanning and colouring substances reach 1.24%, and pectin substances make up 0.77%. The fruit sugars are glucose and fructose, generally in equal quantities. Tanning substances, leicoantocianes, in particular, are responsible for the tart taste; the lower their content is, the less the tart taste is felt, moreover, ripe fruit are less tart in flavour which is due to the tanning substances getting bound with high molecular substances. All the 12 persimmon varieties cultivated in Georgia can be used as raw material, including substandard and overripe fruit that are not marketable and do not have a long shelf life.

Biochemical Composition of Persimmon Fruit (Diospyros kaki L.) Bred in Ukraine

“…Yaqub et al (2016) reported fruit sugariness of 12.5% in Pakistani persimmons, which is comparable to Ukrainian cultivars. In contrast, sugar contents in Georgian fruit ranged from 13.0% to 19.1% (Bejanidze et al 2019), and the sugar content in Turkish fruit was recorded as 16.3% (Altuntas et al 2011) and 14.6% (Candir et al 2009). The titrated acids content in Ukrainian persimmon ranged from 0.12% to 0.32% (Table ).…”

“…The titrated acids content in Ukrainian persimmon ranged from 0.12% to 0.32% (Table ). Baltacioğlu and Artik (2013), recorded that the content of titrated acids in persimmon fruits produced in Turkey ranged from 0.28% to 0.46%, while in Georgia, the titrated acid contents ranged from 0.05% to 0.18% (Bejanidze et al 2019).…”

“…Persimmon belongs to the Ebenaceae family (Díaz et al 2020), with more than 500 species. The quality and taste of the fruit depend on the growing conditions (Bejanidze et al 2019). The People's Republic of China ranks first in the world in the area of cultivation of this crop and produced more than 3.2 million tons (approximately 76.04% of global production) in 2020 (FAO 2021).…”