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4 th International Symposium of Biotechnology10 – 11 th November 2011, Bucharest, RomaniaP.I.9. OENOLOGICAL POTENTIAL OF WINE YEAST ISOLATEDFROM DEALURILE BUJORULUI VINEYARDMATEI RADOI FLORENTINA 1 , GAGEANU ADRIAN 2 ,CIUBUCA AUREL 31 University of Agronomical Sciences and Veterinary Medicine of Bucharest, Faculty of Biotechnology59, Marasti Ave., Bucharest, 010464 Romania, e-mail: florentina.matei@biotehnologii.usamv.ro2 University of Agronomical Sciences and Veterinary Medicine of Bucharest, Faculty of Horticulture,Bucharest, Romania3 SCDVV Bujoru, Tg. Bujor, Galati, RomaniaKeywords: wine yeast biodiversity, oenological potential, Dealurile Bujorului vineyardThis study is part of a national effort towards the increase of Romanian wines visibility andauthenticity in the context of the globalization and standardization of wines in the world. It is wellknown that the specific characters of a wine come in the mean time from the vineyard eco-pedologicalconditions, as well as from the grape variety. Moreover, in the last decade has been demonstratedthat the use of local isolated microorganisms (e.g yeast) improves the wine character.In this context, we have isolated and purified from Dealurile Bujorului vineyard 140 yeaststrains on specific media (must-agar, GYP) and by rapid physiological API 20 C test we performedthe identification. It has been proved that 27 strains belong to the gender Saccharomyces,respectively 19.3% from total strains. All these strains have been pretested in laboratory conditions(200 ml volume) for their fermentative potential on synthetic must and in natural must. The growthcurves for the strains have been determined, as well as the measurement of alcoholic yield. Fromthese 27 strains only 5 have been kept for their oenological capacity.Further, the 5 kept strains (SB 16, SB 27, SB 35, SB 43, SB 56) have been tested on microvinificationconditions (20 l volume) for their oenological potential. The tests have been performed onan autochthonous grape variety for white wines (Feteasca Regala) harvested from DealurileBujorului vineyard, same areal for the yeast isolation.The measurements have proven that the alcoholic content in the final wines varied between12.2 (SB 56) and 14.4 % (SB 35 and SB 43) on a pH level around 3.0. For the residual sugars thebest behaviour have showed SB 56 which lead to less than 1 g/l residual sugar, while SB 27 couldreduce the sugar only to a content of 24,6 g/l. The glycerol formation varied between 5 and 11 g/l, thebest producer being SB 16. There has been also proven that some of these strains have a pelicularcharacter.These strains are now subject to a PCR-ITS amplification for a molecular characterisation.In the mean time, because of the aromatic profile of the obtained wines, identified during winetasting, it is recommended to be performed further HPLC measurements in order to prove thearomatic potential of the strains.39