Grape musts differentiation based on selected aroma compounds using SBSE-GC-MS and statistical analysis

Fifty-one aroma compounds in musts from 'Muscat Ottonel', 'Aligoté', 'Muscat of Alexandria' and 'Pedro Ximénez' white grapes have been determined, three of them identified for the first time in grapes. Two fingerprints for each cultivar, based in 6 groups of aroma compounds before and after acidic hydrolysis of the musts were obtained by Multiple Variable Analysis. Only 17 aroma compounds before and 21 after hydrolysis, were selected by their high discriminating power. The Principal Component Analysis carried out with data of these selected compounds provided two components explaining 85.11 % of the overall variance for free aroma compounds and 87.58 % for those obtained after hydrolysis of musts, allowing an objective differentiation of each cultivar

Minor Volatile Compounds Profiles of ‘Aligoté’ Wines Fermented with Different Yeast Strains

The aroma of wine can be classified accordingly to its origin, in varietal aroma, pre-fermentative aroma, fermentative aroma and post-fermentative aroma. Although a number of flavor components are found in the original grape, the dominant and major compounds contributing to white wines are formed during alcoholic fermentation, in concordance with the yeast strain used. In order to highlight the influence of the yeast strain to the aroma composition of wines,<b> </b>wine samples from ‘Aligoté’ grape variety made with 8 different yeast strains were subjected to stir bar sorptive extraction-gas chromatography-mass spectrometry (SBSE-GC-MS) analyses. Also, a sensorial analysis of the studied wines was performed by a tasting panel consisting of 15 tasters. 38 minor volatile compounds were quantified by SBSE-GC-MS technique. Different concentration of the same compound and different aroma compounds were identified and quantified in wines obtained with different yeast strains. A wine finger printing was obtained by multivariate data analyses of aroma compounds grouped by chemical families. The analytical and sensorial analysis of the wine samples confirms that there are differences in aroma composition of the wines made with different yeast strains

Mesoporous materials as fining agents in variety Cabernet Sauvignon wines

Innovative oenological products and techniques constantly need to be optimized in order to produce high quality wines that are able to fulfill the demanding consumers, with a pleasant colour, astringency, bitterness and a balanced organoleptic profile. New mesoporous materials with viability and environmental safety characteristics, might be a feasible alternative to the use of bentonite, while nowadays in the winemaking there is a major challenge caused by wastes derivate mainly from wine clarification stages. This study was aimed at investigating the influence of conventional (bentonite and activated coal) and alternative (MCM-41, SBA-15, KIT-6) fining agents on enological parameters, colour, as well as on the antioxidant activity of a Cabernet Sauvignon wines. Our results show that mesoporous materials, KIT-6 and SBA-15 (6 g/L) present the highest reduction on antioxidant activity with 23.08% and 24.41%, while bentonite and activated coal (1.5 g/L) reduced with 20.72%, respectively 33.18%. Cluster analysis performed with the values of antioxidant activity differentiated wines treated with activated carbon from other wines