Cultivar and year effects on the chemical composition of elderberry (Sambucus nigra L.) fruits

Due to their outstanding anthocyanin content, elderberries are mainly used in the food industry to produce pigment concentrations. Thanks to the increase in demand, elderberry is grown on ever greater areas in Hungary and in neighbouring countries. Cultivar use, however, is very one-sided, being practically restricted to 'Haschberg'. As this cultivar has many negative properties, growers have begun to plant and test new cultivars. When determining the commodity value of cultivars, it is important to examine not only the physical traits of the fruit, but also their main chemical parameters. In the present experiment the chemical properties (soluble solids and titratable acid content, total polyphenol and anthocyanin content, antioxidant capacity) of the fruit of 11 elderberry cultivars ('Haidegg 13', 'Haiden 17', 'Haschberg, K3, 'Korsor', 'Samdal', 'Samidan', 'Samocco', 'Sampo', 'Samyr, Weihenstephan') were analysed in three consecutive years. In addition to the comparative evaluation of the cultivars, this work also aimed to discover correlations between the components and to study the effect of the year on the chemical composition of the fruit. Significant differences were found between the cultivars for the soluble solids content (F(10;8.74)=9.71; p=0.001), the titratable acid content (F(10;22)=7.91; p<0.001), the polyphenol content (F(10;22)=9.77; p<0.001), the anthocyanin content (F(10;8.52)=36.18; p<0.001) and the antioxidant capacity (F(10;22)=3.61; p=0.006). A year effect was proved for the water-soluble solids content (F(2;30)=4.02; p=0.028) and the antioxidant capacity (F(2;30)=5.21; p=0.011). Among the chemical properties, a significant positive linear correlation was only detected between the polyphenol and anthocyanin contents (r=0.91; p<0.001). Among the cultivars, 'Sampo', 'Samidan' and Weihenstephan' exhibited outstanding polyphenol and anthocyanin contents. The soluble solids content and antioxidant capacity of 'Haidegg 17' were also promising.