The composition of fruit of different strawberry varieties depending on maturity stage

The fruits of the cultivars ‘Eros’, ‘Selena’, ‘Northaester’, ‘Fern’, ‘Simphony’, ‘Mohawk’, ‘Elsanta’, ‘Miss’, ‘Evita’, ‘Marmolada’, ‘Pegasus’, ‘Kent’ and ‘Cortina’ were chemicaly analysed. With the high-performance liquid chromatography (HPLC) method the individual sugars (sucrose, glucose, fructose and xylose) and organic acids (citric, fumaric and shikimic) were estimated in two different stages of ripeness: the stage of technological ripeness and the stage of complete ripeness. Statistical differences among the fruits of the same cultivar and of different maturity stages were established in the contents of glucose, fructose, xylose, fumaric and shikimic acids, but there were no statistical differences in the contents of sucrose and citric acid. Among the fruits in the stage of complete ripeness the cvs. ‘Mohawk’ and ‘Evita’ were outranking with regard to the content of sucrose, while the fruits of the cvs. ‘Fern’ and ‘Northaester’ attained the highest contents of glucose, fructose and citric acid. During the same time of ripeness the highest content of total soluble solids (TSS) was measured in the cv. ‘Mohawk’, and the lowest content of TSS was exhibited by the cv. ‘Miss’. The results of the analyses conducted during the research confirm that the chemical composition of strawberry fruits significantly varied among the genotype of the plant and on the stage of maturity of fruits. Therefore harvesting in optimal fruit bearing time is essential for achieving good quality of strawberries, since important changes in the content of individual sugars and acids occur in the last period of maturity as well.