Stable isotope ratio analysis of different European raspberries, blackberries, blueberries, currants and strawberries

To date the stable isotope ratios of berries have never been extensively explored. In this work the H, C, N and O isotopic ratios of 190 samples of different soft fruits (strawberries, raspberries, blueberries, blackberries and currants) produced in a northern Italian region and at two sites in Romania and Poland collected over three harvest years are presented and discussed. The different soft fruits showed a typical range for one or more isotopic parameters that can be used to verify the authenticity of the fruit composition declared on the label. The δ¹³C and δ¹⁵N of pulp and the δ¹⁸O of juice can be considered effective tools for identifying the different geographical origin of fruit. A significant effect of crop cover on juice δ¹⁸O and fertilisation practices on pulp δ¹⁵N was demonstrated and must be considered with attention when evaluating data.