The aim of the study was to investigate the impact of the on-vine double maturation raisonnée (DMR) and off-vine berry partial dehydration in the chamber (PDC) on the chemical characteristics of the grape and wine grapevine cultivar Refošk. | Turkish Journal of Agriculture and Forestry Research Article Turk J Agric For (2017) 41: 10-22 © TÜBİTAK doi: Effects of partial dehydration techniques on the metabolite composition in ‘Refošk’ grape berries and wine* 1, 2 1 1 Maja MIKULIC-PETKOVSEK *, Tjasa JUG , Jan RESCIC , Denis RUSJAN Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia 2 Chamber of Agriculture and Forestry of Slovenia, Institute for Agriculture and Forestry, Nova Gorica, Slovenia 1 Received: Accepted/Published Online: Final Version: Abstract: The aim of the study was to investigate the impact of the on-vine double maturation raisonnée (DMR) and off-vine berry partial dehydration in the chamber (PDC) on the chemical characteristics of the grape and wine grapevine cultivar ‘Refošk’. A liquid chromatography-mass spectrometry (LC-MS) system was used for the identification and quantification of phenolics and the HPLC for sugars and organic acids. Berries subjected to DMR partial dehydration reached technological maturity ( °Brix) within 14 days of cane cutting and those under PDC in 22 days upon harvest. The greatest decline in berry weight was recorded in the PDC treatment (14%), followed by the DMR technique (approx. 8%). Both dehydrations significantly increased titratable and total acidity in berry and wine, while the pH level was significantly lower in DMR treated berries. Compared to PDC, DMR significantly increased the content of total flavonols and anthocyanins in berries and wine, as well as the total flavanols in berries and stilbenoids in wine. DMR treated berries contained higher content of total anthocyanins, up to 2-fold higher content of total flavonols, and higher total phenolic content in the skin compared to those from PDC treatment. Moreover, it increased the content of total anthocyanins, stilbenoids, and flavonol
