Μελέτη επίδρασης της μηλογαλακτικής ζύμωσης σε ποιοτικά χαρακτηριστικά των λευκών οίνων των ποικιλιών Αηδάνι και Ασύρτικο με χρήση διαφορετικών στελεχών του γαλακτικού βακτηρίου Oenococcus oeni.

Abstract

In this thesis, the effect of malolactic fermentation on white wines of the varieties Aidani and Assyrtiko from the region of Santorini was studied. Especially, the purpose of this study was to find the influence of concentration of malic acid and the strain of lactic acid on kinetics of malolactic fermentation and the sensory characteristics of the final wine. Two different commercial strains of lactic acid bacteria of the species Oenococcus oeni, the strain VP41 (Lallemand) and the strain B7 (Laffort) were used. The above bacteria were added to the wines of the same variety and were inoculated separately and in different concentration of malic acid. During the experimental procedure, analyzes were performed to determine the malic acid in the samples by enzymatic KIT. Then, after the malolactic fermentation had taken place in the wines, the chemical parameters were quantified using the WineScan Flex machine of the company FOSS. In the end, the wines were evaluated in terms of their quality features. The research who conducted showed that application of lactic acid bacteria in white vinification has a significant effect on the sensory profile of the wines produced. Specifically, in the wine with the Aidani variety it was found that the use of the lactic acid bacterium B7 was better suited, as it gave a more intense floral aroma than the VP41 strain. On the contrary, Assyrtiko had a more pronounced fruity character in the samples to which the lactic acid bacterium VP41 had been added. Regarding the effect of malic acid concentration, the wines with the highest concentration showed lower volatile acidity in both varieties.