terclim by ICS banner
IVES 9 IVES Conference Series 9 INSIGHT THE IMPACT OF GRAPE PRESSING ON MUST COMPOSITION

INSIGHT THE IMPACT OF GRAPE PRESSING ON MUST COMPOSITION

Abstract

The pre-fermentative steps play a relevant role for the characteristics of white wine [1]. In particular, the grape pressing can affect the chemical composition and sensory profile and its optimized management leads to the desired extraction of aromas and their precursors, and phenols resulting in a balanced wine [2-4]. These aspects are important especially for must addressed to the sparkling wine as appropriate extraction of phenols is expected being dependent to grape composition, as well. To the best of our knowledge, a gap exists regarding grape composition – pressing conditions – must composition. To fulfill this gap and support the wine industry, this research aimed to clarify the impact of grape pressing based on both grape and must composition.

Chardonnay (7 samples) and Pinot blanc (2 samples) grapes were collected in vintage 2022 from different vineyards in Franciacorta area (Lombardy, Italy). These grapes were used to produce musts under an industrial scale following the pressing conditions adopted by wineries. Must samples were obtained at different extraction yields (e.g. running juice, 20, 30 [first fraction], 40, 50 [second fraction], 60 and 70 [third fraction] % must yields). The chemical parameters, turbidity units (NTU), color index (ABS 420 nm), total phenol index (TPI), polyphenol oxidase (PPO) activity and antioxidant capacity (AC) were assessed in both grape and must samples.

A decreasing trend of readily assimilable nitrogen and titratable acidity was found in must samples with higher extraction yields, while the opposite was observed for pH, NTU, color index, TPI and AC with a different extend dependent from the grape varieties and pressing conditions. Considering the first fraction must, a high variability in phenol extraction was found, from 16% to about 35%. Such a difference could be attributable to the different pressing conditions adopted as comparable levels of TPI were detected in grapes used (1.7-2.2 g/L, RDS=10%). The PPO activity seemed to be unaffected by the increased must extraction yield. Grape variety was influential on phenol content for the same must yield being higher for Pinot blanc probably due to its thinner skin in comparison to Chardonnay.

This study suggests the phenol-related indexes should be considered in addition to the chemical parameters for the accurate management of the pressing step; it also has been clarifying the relation existing between the composition of grape and must.

 

1. Gawel R., Day M., Van Sluyter S.C., Holt H., Waters E.J., Smith P.A. (2014). White wine taste and mouthfeel as affected by juice extraction and processing. J. Agric. Food Chem. 62, 10008–10014. https://doi.org/10.1021/jf503082v
2. Ferreira-Lima N.E., Burin V.M., Caliari V.,  Bordignon-Luiz M.T. (2016). Impact of pressing conditions on the phenolic com-position, radical scavenging activity and glutathione content of Brazilian Vitis vinifera white wines and evolution during bottle ageing. Food Bioprocess. Technol. 9, 944–957. https://doi.org/10.1007/s11947-016-1680-7
3. Lukic I., Horvat I., Radeka S., Damijanic K., Staver M. (2019). Effect of different levels of skin disruption and contact with oxy-gen during grape processing on phenols, volatile aromas, and sensory characteristics of white wine. J. Food Process. Preserv. 201943, e13960. https://doi.org/10.1111/jfpp.13969
4. Del Fresno J.M., Cardona M., Ossorio P., Loira I., Escott C., Morata A. (2021). White must extraction. In: White Wine Techno-logy. Academic Press. https://doi.org/10.1016/B978-0-12-823497-6.00013-2

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Gvantsa Shanshiashvili¹, Marta Baviera¹, Antonio Tirelli¹, Daniela Fracassetti1,*

1. Department of Food, Environmental and Nutritional Sciences (DeFENS), Università degli Studi di Milano, Via G. Celoria 2, 20133 Milan, Italy 

Contact the author*

Keywords

White grape, Must extraction, Sparkling wine, Phenols

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

PERCEPTUAL INTERACTIONS PHENOMENA INVOLVING VARIOUS VOLATILE COMPOUND FAMILIES LINKED TO SOME FRUITY NOTES IN BORDEAUX RED WINES

Fruity notes play a key role in the consumer’s appreciation of Bordeaux red wines. If literature provides a lot of knowledge about the nature of volatile compounds involved in this fruity expression, the sensory phenomena involving these compounds in mixture still need to be explored. Considering previous sensory works about the impact of esters and some overripening compounds, the goal of this work was to study the implication of perceptual interactions involving red wine odorant compounds of diverse origins and described as potentially affecting fruity aromatic expression.

Read More

UNRAVELING THE CHEMICAL MECHANISM OF MND FORMATION IN RED WINE DURING BOTTLE AGING : IDENTIFICATION OF A NEW GLUCOSYLATED HYDROXYKETONE PRO-PRECURSOR

During bottle aging, the development of wine aroma through low and gradual oxygen exposure is often positive in red wines, but can be unfavorable in many cases, resulting in a rapid loss of fresh, fruity flavors. Prematurely aged wines are marked by intense prune and fig aromatic nuances that dominate the desirable bouquet achieved through aging (Pons et al., 2013). This aromatic defect, in part, is caused by the presence of 3-methyl-2,4-nonanedione (MND). MND content was shown to be lower in nonoxidized red wines and higher in oxidized red wines, which systematically exceeds the odor detection threshold (62 ng/L).

Read More

NEAR INFRARED SPECTROSCOPY FOR THE ESTIMATION OF TEMPRANILLO BLANCO VOLATILE COMPOSITION ALONG GRAPE MATURATION

Grape volatile compounds are mainly responsible for wine aroma, so it is important to know the va-rietal aromatic composition throughout ripening process. Currently, there are no tools that allow mea-suring the aromatic composition of grapes, in intact berries and periodically, throughout ripening, in the vineyard or in the winery. For this reason, this work evaluated the use of near infrared spectroscopy (NIR) to estimate the aromatic composition and total soluble solids (TSS) of Tempranillo Blanco berries during ripening. For this purpose, NIR spectra (1100-2100 nm) were acquired from 240 samples of in-tact berries, collected at different dates, from veraison to overripening.

Read More

EFFECT OF DIFFERENT VITICULTURAL AND ENOLOGICAL PRACTICES ON THE PHENOLIC COMPOSITION OF RED WINES

Global climate change is exerting a notable influence on viticulture sector and grape composition. The increase in temperature and the changes in rainfall pattern are causing a gap between phenolic and technological grape maturities [1]. As a result, the composition of grapes at harvest time and, consequently, that of wines are being affected, especially with regards to phenolic composition. Hence, wine quality is decreasing due to changes in the organoleptic properties, such as color and astringency, making necessary to implement new adaptive technologies in wineries to modulate these properties in order to improve wine quality.

Read More

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.

Read More