Grapes from the geographical areas of the Black Sea: Agroclimatic growing conditions and evaluation of stable isotopes compositions in scientific study

Abstract

The report considers the agroclimatic conditions in the Black Sea districts of cultivation and processing of grapes - the Black Sea Lowland, the Crimean Peninsula and the South-west coastal areas of the Greater Caucasus. The IRMS/SIRA techniques - Flash combustion (FC-IRMS/SIRA) & Isotopic equilibration (EQ-IRMS/SIRA) - were first applied for the evaluation of carbon and oxygen isotopes ratios in the components of grapes from the Crimean Peninsula. The 13 C/12 C ratios were studied by the FC-IRMS/SIRA in carbohydrates and organic acids in authentic samples of 8 grape varieties from the 2015 harvest. The EQ-IRMS/SIRA was applied to measure the 18 O/16 O ratios in intracellular water of grapes. The measured δ13 CVPDB value ranges from − 25.01 to − 21.01‰ (for carbohydrates), and from − 25.09 to − 21.30‰ (for organic acids). To evaluate the extent of biological isotope fractionation the 18 O/16 O ratios were measured in ground water and water of atmospheric precipitates from the Crimean Peninsula. Compared to ground (δ18 OVSMOW from − 10.85 to − 8.14‰) and atmospheric (average δ18 OVSMOW − 2.85‰) waters, the intracellular water of Crimean grape varieties is found to be enriched with 18 O isotope. The δ18 OVSMOW value of the grape intracellular water varies from 2.34 to 5.29‰ according to agroclimatic conditions of the season in 2015.