terclim by ICS banner
IVES 9 IVES Conference Series 9 ASSESSMENT OF ‘DOLCETTO’ GRAPES AND WINES FROM DIFFERENT AREAS OF OVADA DOCG

ASSESSMENT OF ‘DOLCETTO’ GRAPES AND WINES FROM DIFFERENT AREAS OF OVADA DOCG

Abstract

Dolcetto (Vitis vinifera L.) is one of the traditionally cultivated varieties in Piedmont (north-east Italy). Dolcetto wines have long been associated with local consumption and they are little known internationally. In particular, the Ovada area (south-east Piedmont), even if it represents a small share of the regional PDO Dolcetto production, is one of the oldest and vocated territory, giving wine also suitable for aging. In this study, the basic composition and phenolic content of Dolcetto grapes for Ovada DOCG wines have been investigated in three different vintages (2020-2022), as well as the main aspects of the derived commercial and experimental wines (basic parameters, phenolics, volatile compounds, sensory properties).

Grapes from fifteen vineyards, belonging to three Ovada DOCG areas, were harvested at the same grape soluble solids content (about 13.0-13.5% v/v potential alcohol) and were evaluated in terms of basic traits, phenolic ripeness, and skins and seeds phenolic composition. The commercial wines produced from these vineyards were analyzed for 2020 and 2021 vintages. Among them, representative vineyards were also selected for experimental standardized winemaking to establish correlations between grapes and wines results.

The results showed different acidic content at harvest, with higher values for area 3 that resulted also in lower sugar content, and differences among the vintages studied according to the weather conditions (2020 was wetter than 2021 and 2022). The phenolic ripeness parameters changed moderately among the three areas, even though the cell maturity index (EA%) and the seed maturity index (Mp%) reported no significant differences, with a higher vintage effect. The berry skins phenolic composition differed among areas, being the lower values of total polyphenols, total flavonoids, and total anthocyanins observed in area 1. Significant differences for polyphenols were found depending also on the vintage. Moreover, the seasonal conditions affected the berry weight, increasing the seeds polyphenols ratio on the total content in the drier years (2021-2022) although with different extent depending on the area. The results on experimental wines could be useful to assess if they correspond to those predicted from grape analysis, helping winemakers in improving vinification protocols according to the desired wine style. Acknowledgements. We thank the Consorzio di Tutela dell’Ovada DOCG and its associates for supporting this study.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Motta G. ¹, Paissoni M.A. ¹, De Paolis C. ¹, Beria d’Argentina, S. ¹, Kukharenko O. ¹, Liscio G.P. ¹, Giacosa S. ¹, Río Segade S. ¹, Cagnasso E. ¹, Gerbi V. ¹, Rolle L. ¹

1. University of Torino, Department of Agricultural, Forest and Food Sciences, Corso Enotria 2/C, 12051 Alba (CN), Italy

Contact the author*

Keywords

Dolcetto, phenolic content, autochthonous varieties, red wines

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

PINKING PHENOMENA ON WHITE WINES: RELATION BETWEEN PINKING SUSCEPTIBILITY INDEX (PSI) AND WINE ANTHOCYANINS CONTENT

Pinking is the emergence of pink tones in white wines exclusively produced from white grape varieties, known as pinking phenomena for many years. Pinking is essentially appeared when white wines are produced under reducing conditions [1,2,3]. Pinking usually occurs after bottling and storage of white wines, but its appearance has also been described after alcoholic fermentation or even as soon as the grape must is extracted [4]. Therefore, the purpose of this work was to investigate the existence of an-thocyanins in white wines made from different white grape varieties and grown locations and critically evaluate the most common method used for predicting pinking appearance in white wines: the Pinking Susceptibility Index (PSI).

CHARACTERIZATION OF ENOLOGICAL OAK TANNIN EXTRACTS BY MULTI-ANALYTICAL METHODS APPROACH

Oak tannin extracts are commonly used to improve wine properties. The main polyphenols found in oak wood extracts are ellagitannins¹ that release ellagic acid upon hydrolysis and comprise numerous structures². Moreover, oak tannin extracts contain other compounds giving a complex mixture. Consequently, the official OIV method based on gravimetric analysis of the tannin fraction adsorbed on polyvinylpolypyrrolidone is not sufficient to describe their composition and highlight their chemical diversity.

NEW INSIGHTS INTO THE FATE OF MARKERS INVOLVED IN FRESH MUSHROOM OFF-FLAVOURS DURING ALCOHOLIC FERMENTATION

The fresh mushroom off-flavour (FMOff) has been appearing in wines since the 2000s. Some C8 compounds such as 1-octen-3-one, 1-octen-3-ol, 1-hydroxyoctan-3-one, 3-octanol and others are involved in this specific off-flavour [1-3]. At the same time, glycosidic precursors of some FMOff compounds have been identified in musts contaminated by Crustomyces subabruptus [4], highlighting the role of aroma precursors in this specific taint. However, the fate of these volatile molecules and glycosidic fractions during fermentation is not well known.

IMPACT OF NEW BIO STIMULANTS ON GRAPE SECONDARY METABOLITES UNDER CLIMATE CHANGE CONDITIONS

In a context of climate change and excessive use of agrochemical products, sustainable approaches for environmental and human health such as the use of bio stimulants in viticulture represent a potential option, against abiotic and biotic threats. Bio stimulants are organic compounds, microbes, or a combination of both, that stimulate plant’s vital processes, allowing high yields and good quality products. In vines, may trigger an innate immune response leading to the synthesis of secondary metabolites, key compounds for the organoleptic properties of grapes and wines.

WINE LEES AS A SOURCE OF NITROGEN FOR OENOCOCCUS OENI TO IMPROVE MALOLACTIC FERMENTATION PERFORMANCE

Malolactic fermentation (MLF) is a desired process in red and acidic white wines, after alcoholic fermentation (AF), carried out by the lactic acid bacterium (LAB) Oenococcus oeni. The advantages are an increase of pH, microbiological stabilization and organoleptic improvement of the final wine. However, the presence of stress factors such as ethanol, low pH, high total SO2, lack of nutrients and presence of inhibitors, could affect the successful completion of MLF [1]. Changes in amino acid composition and deficiencies in peptides after AF, showed that MLF can be delayed, signaling its importance for bacterial growth and L-malic acid degradation during MLF [2].