Enological characters of thirty vines in four different zones of Tuscany

AIM AND METHODS: Corvina and Corvinone are the two main grape varieties used in the production of Valpolicella, Recioto and Amarone, top-quality red wines in north-eastern Italy. This work aimed at determining the aroma composition of Corvina and Corvinone experimental wines and identify the main aroma compounds contributing to the aroma characteristics of Corvina and Corvinone monovarietal wines. Five Corvina and five Corvinone wines were studied, the grapes coming from five different vineyards in Valpolicella. Volatile compounds were extracted by SPE and identified and quantified by gas chromatography-mass spectrometry (GC-MS), whereas their aroma impact was determined by gas chromatography- olfactometry (GC-O).RESULTS: Based on the GC-MS-O analysis, 95 odor zones were detected, from which 68 compounds were successfully identified. Using the criterion of a value higher than 30% in modified frequency (MF %), 51 compounds were selected and grouped according to odor similarity. Compounds with values below 30% were discarded.

Assyrtiko is a rare ancient grape variety that constitutes one of the most popular in Greece. The objective of the current research was to evaluate indigenous Saccharomyces cerevisiae isolates as fermentation starters and also test the possible strain impact on volatile profile of Assyrtiko wine. 163 S. cerevisiae isolates, which were previously selected from spontaneous alcoholic fermentation, were identified at strain level by interdelta-PCR genomic fingerprinting. Yeasts strains were examined for their fermentative capacity in laboratory scale fermentation on pasteurized Assyrtiko grape must.

Climate change leads to even more hostile and stressful for the wine microorganism conditions and consequently issues with fermentation rate progression and off-character formation are frequently observed. The objective of the current research was to classify a great collection of yeast isolates from Greek wines based on their technological properties with oenological interest. Towards this direction, fourteen spontaneously fermented wines from different regions of Greece were collected for further yeast typing. The yeast isolates were subjected in molecular analyses and identification at species level.

The present study was performed in a traditional winery located in the viticultural area of Brunello di Montalcino, Siena, Italy, in the vintage 2015. Actually, in this winery Sangiovese grape musts are fermented in large oak barrels by a single strain of Saccharomyces cerevisiae previously isolated in the same winery. Pumping over operations are carried out once or twice a day until the end of alcoholic fermentations. The aim of this work was to investigate on the oenological properties of Sangiovese wine produced with the traditional winemaking process adopted by the winery under study obtained from the fermentation of whole berries compared to that from crushed grape must. In particular, two lots of 65q of Sangiovese grapes from the same 3ha vineyard were vinified in 150hL oak barrels.

The universalization in wine production has been restricting the imprint of terroir in regional wines, resulting in loss of typicity. Microbes are the main driving force in wine production, conducting fermentation and originating a myriad of metabolites that underly wine aroma. Grape berries harbor an ecological niche composed of filamentous fungi, yeasts and bacteria, which are influenced by the ripening stage, cultivar and region. The research project GrapeMicrobiota gathers a consortium from University of Zaragoza, University of Minho and University of Tours and aims at the isolation of native yeast strains from berries of the wine region Douro, UNESCO World Heritage, towards the production of wines that stand out in the market for their authenticity and for reflecting their region of origin in their aroma.