Characteristics of some Montefalco Sagrantino vineyards through polyphenolic components

The characterization of « the soil effect » in vine growing is often limited to the description of the physical components of the terroir. Many works were done in this direction and corresponded to geological, pedological or agronomical approaches. However, if the physical environment influences the vine and its grapes, its effect becomes limited at the scale of exploitation. Thus, it could be important to consider how the viticulturist « translated » the potential.

I territori della Riserva Geologica del Piacenziano sono parte del pedeappennino piacentino e sono noti per essere la culla del Pliocene, quel periodo di storia della Terra compreso tra 5.3 e 1.8 milioni di anni fa. Gli strati argillosi e sabbiosi riccamente fossiliferi qui presenti sono da sempre oggetto di studi geo-paleontologici tant’è che il Pliocene medio (3.6-2.6 milioni di anni fa) è internazionalmente noto come Piacenziano. Le analisi sensoriali strutturate dei vini qui prodotti hanno evidenziato, soprattutto per il vino Monterosso, le positive peculiarità dei loro caratteri sensoriali e descritto gli scostamenti significativi del loro profilo sensoriale rispetto agli altri vini presi a riferimento.

Today winegrowers involved in mechanical winter pruning are applying this viticultural technique on two main training systems, the free cordon, appearing to be the more efficient, and the trellised vertical shoot positioning (VSP) system. The main reasons for maintaining the trellis are generally due to common habits in vineyard management, risk of wind damage for the shoots, or risk of decrease in photosynthesis potential. The aim of the study was to assess the effects of the two training systems on vine. In addition, different nitrogen fertilization levels were applied on the two systems to evaluate the best combination to achieve yield and grape quality.

The fortress of the Herodium, built towards the end of the first century BCE/ante Cristo, on the orders of Herod the Great, Roman client king of Judea, attests the expansion of Roman influence in the eastern Mediterranean. During archaeological excavations of the Herodium in 2017[1], a winery was discovered on the ground floor of the palace, with an assortment of clay vessels in situ, including large dolia – clay fermentation vessels each capable of fermenting up to 300-400 L of wine. Thanks to the recent progresses in the field of paleogenomics[2], we could analyse the organic material consistent with grape pomace at the bottom of these vessels, by extracting and sequencing the DNA using shotgun metagenomics and targeted capture, aiming for enrichment of DNA from fermentation associated microbes.

Odours deemed harmful by the consumer and described as “stable”, “horse sweat” or “burnt plastic” can be found in wines. The responsible molecules are volatile phenols, produced by a spoilage yeast: brettanomyces bruxellensis. This species is particularly well adapted to the wine environment and can resists many stresses such as a high alcohol level, a low ph or high levels of SO2, more or less efficiently depending on the strain considered.