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Grape-associated microbial community is influenced by a combination of viticultural, climatic, pedological and anthropological factors, collectively known as terroir. Therefore, grapes of the same cultivar grown in different areas can be appreciated for their distinctive biogeographic characteristics. In our previous study, we showed that the phenotypic response of Aglianico and Cabernet grapevines from Molise and Sicily regions is significantly influenced by the prevailing pedoclimatic conditions, particularly soil physical properties. However, the scale at which microbial communities differ could be important in clarifying the concept of terroir, including whether it is linked to the grape variety present in a particular vineyard. To explore this further, in the research presented here, a comparative study on the fungal communities inhabiting the berry surfaces of Cabernet and Aglianico cultivars was conducted on different vineyards located in Southern Italy (Molise, Sicily and Campania regions, the first two of which had been involved in our previous study) by using high-throughput sequencing (HTS) and multivariate data analysis. The descriptive approach through relative abundance analysis showed the most abundant phyla (Ascomycota, Basidiomycota, and Chytridiomycota), families (Cladosporiaceae, Saccotheciaceae, Pleosporaceae, Saccharomycodaceae, Sporidiobolaceae, Didymellaceae, Filobasidiaceae, Bulleribasidiaceae, and Saccharomycetaceae) and genera (Cladosporium, Aureobasidium, Alternaria, Stemphylium and Filobasidium) detected on grape berries. The multivariate data analysis performed by using different packages (phyloseq, Vegan, mixOmics, microbiomeMarker and ggplot2) highlighted that the variable "vineyard location" significantly affect the fungal community, while the variable "grape variety" has no significant effect. Thus, some taxa are found to be part of specific vineyard ecosystems rather than specific grape varieties, giving additional information on the microbial contribution to wine quality, thanks to the presence of fermentative yeasts or, conversely, to the involvement in negative or detrimental roles, due to the presence of grape-deriving fungi implied in the spoilage of wine or in grapevine pathogenesis. In this connection, the main functions of core taxa fungi, whose role in the vineyard environment is still poorly understood, are also described. [ABSTRACT FROM AUTHOR]

In industrial winery, the use of mixed starter cultures composed of Saccharomyces and non-Saccharomyces yeasts is an approach of growing importance for winemakers to enhance the sensory and complexity of the wine without compromising the quality. In this work, the oenological properties and enzymatic activities of 196 non-Saccharomyces yeasts, belonging to Hanseniaspora guilliermondii and Hanseniaspora uvarum species, were investigated. This screening has allowed the selection of the best non-Saccharomyces yeast strain and the use of vinification for white grape of Campania Vitis vinifera cv Fiano, in an industrial scale. The experimental fermentations were performed in four different batches: batch A (H. guilliermondii BF1 and S. cerevisiae 404 in sequential inoculum); batch B only inoculum of S. cerevisiae 404; batch C without inoculation (spontaneous fermentation); batch D with the inoculum of H. guilliermondii BF1 strain. The results of chemical and sensorial analyses have showed that the best wine comes from batch A. In conclusion, the use of H. guilliermondii BF1 with good oenological properties and a strong β-glucosidase activity allowed to improve the sensorial complexity of the wine. Selected non-Saccharomyces yeast could be applied profitably to winemaking to enhance the quality of the wine using new fermentation technologies, and could be used in industrial winery. [ABSTRACT FROM AUTHOR]

Tintilia is an autochthonous grapevine of the Italian Molise region which risked to disappear. However, recently, the production of Tintilia red wines is resuming and in the year 2011 the protected designation origin 'Tintilia del Molise' was officially registered. In this work, an analytical characterization of representative red wines from Tintilia grape is reported. A total of 36 different physicochemical variables were determined and discussed, considering those with an estimated coefficient of variation <25 % as more characterizing. These were found to be (mean): density (0.9949); dry extract (34.4 g L) and ashes (3.8 g L); ethyl alcohol (14.2 mL 100 mL), glycerol (9.2 g L) and total higher alcohols (1.7 g L); pH (3.65); the titratable (5.9 g L), fixed (5.4 g L), and salified (2.5 g L) acidity; buffering capacity (52.6 mM/L/pH); total phenols (2,341 mg mL); total flavonols (223 mg mL) and epicathechin (75.0 mg mL); %Red (49.1 %) and %Yellow (43.6 %). Sensory analysis was also performed by professional wine tasters. Finally, the Tintilia results were compared with those of Montepulciano wines. Findings of this analytical study describe the Tintilia red wine as a full-bodied wine; alcoholic; with feeble, but stable acidic profile; rich of phenols, especially flavonols; and finally, with a color balanced between red and yellow pigments. [ABSTRACT FROM AUTHOR]

Lactobacillus plantarum strains have resistance mechanisms that enable them to survive and proliferate in wine, which makes them potential malolactic fermentation (MLF) starter cultures. This work focused on the technological characterization of 11 L . plantarum strains isolated from Southern Italian wines that undergo spontaneous MLF, and proposes a selection of new L . plantarum malolactic starters. These strains were characterized according to their oenological characteristics, their ability to produce biogenic amines and bacteriocins, their response to the presence of phenolic compounds, their enzymatic activities and their ability to produce wine odorant aglycones from odourless grape glycosidic aroma precursors. Finally, the malolactic activity of one selected strain was assessed in Cabernet Sauvignon wine, using two inoculation methods. L . plantarum strains tested were not producers of biogenic amines. In particular, the M10 strain showed a good resistance to high levels of ethanol and low pH, it has a good malolactic performance and β-glucosidase activity, this last one demonstrated both directly through the measurement of this enzymatic activity and indirectly by following the release of volatile aglycones from commercial and natural grape glycosidic odourless precursors. These results demonstrated the potential applicability of M10 as a new MLF starter culture, especially for high-ethanol wines. [ABSTRACT FROM AUTHOR]