STSM3 Report Johann Martinez

HPLC-MS analysis of the flavonoid profile of grape berry skins

Johann Martinez Luscher visited Prof. Eric Gomès (31 days in October 2012)

HPLC-MS analysis of the flavonoid profile of grape berry skins at maturity under UV-B.

Viticulture faces the challenge of satisfying high quality standards under variable conditions. The grapes exposure to the sun, and UV-B radiation, is a highly variable factor due to different viticulture techniques. Hereby, vineyards are frequently pruned in order to reduce de vigor of the vines and control the berry maturation. Therefore, an experiment was conducted to elucidate the effect of UV-B and other climatic factors such as elevated temperature and elevated CO2. The aim of this STSM at the Istitut des sciences de la vigne et du vin (ISVV) was to analyze some well-valued metabolites for red wine production.

During the STSM high performance liquid chromatography and mass spectrometry was used to identify and quantify the amount of flavonoids present in berry skin samples. Results show how higher temperatures combined with CO2 can reduce the amount of anthocyanins in the berries, however, flavonols can increase as UV-B exposure increases.

A publication with the participant institutions will be prepared, and it will be included in the candidate´s PhD thesis as a chapter. Hence, thanks to this STSM founded by the COST action FA0906 the candidate had the chance to reinforce the bond between the University of Navarra and the ISVV.