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…

METABOLIC INTERACTIONS OF SACCHAROMYCES CEREVISIAE COCULTURES: A WAY TO EXTEND THE AROMA DIVERSITY OF CHARDONNAY WINE

Yeast co-inoculations in winemaking have been investigated in various applications, but most often in the context of modulating the aromatic profiles of wines. Our study aimed to characterize S. cerevisiae interactions and their impact on wine by taking an integrative approach. Three cocultures and corresponding pure cultures of S. cerevisiae were characterized according to their fermentative capacities, the chemical composition and aromatic profile of the associated Chardonnay wines. The various strains studied within the cocultures showed different behaviors regarding their development.

Read More

EFFECTS OF HYDROXYTYROSOL ON THE CHEMICAL PROFILE AND SENSORY ATTRIBUTES OF A RED TUSCAN WINE

The chemical profile and sensory attributes were studied in Borrigiano IGT Toscana wine (Italy), a blend of Sangiovese 85% and Cabernet Sauvignon 15% grapes harvested in September 2020, where 2-(3,4-dihydroxyphenyl)ethanol (hydroxytyrosol, HT, [1]) was added to a 750-ml wine bottle in 3 different amounts (30, 60, 120 mg) and compared with the control (no HT addition). The study aimed to evaluate whether Polyphenol-HT1®, a high purity HT (>99%) produced by Nova Mentis using biotechnology, could be used as a supplement to sulfites and how it would impact the sensory and chemical profile of this wine [2]. Each sample was prepared in triplicate.

Read More

AROMATIC AND FERMENTATIVE PERFORMANCES OF HANSENIASPORA VINEAE IN DIFFERENT SEQUENTIAL INOCULATION PROTOCOLS WITH SACCHAROMYCES CEREVISIAE FOR WHITE WINEMAKING

Hanseniaspora vineae (Hv) is a fermenting non-Saccharomyces yeast that compared to Saccharomyces cerevisiae (Sc) present some peculiar features on its metabolism that make it attractive for its use in wine production. Among them, it has been reported a faster yeast lysis and release of polysaccharides, as well as increased ß-glucosidase activity. Hv also produces distinctive aroma compounds, including elevated levels of fermentative compounds such as ß-phenylethyl acetate and norisoprenoids like safranal. However, it is known for its high nutritional requirements, resulting in prolonged and sluggish fermentations, even when complemented with Sc strain and nutrients.

Read More

PESTICIDE RESIDUES IN THE VINEYARD ENVIRONMENTS: VINE LEAVES, GRAPE BERRIES, WINES, HONEYBEES AND ASIAN HORNETS

Synthetic pesticides are widely used in viticulture to ensure steady harvest quality and quantity. Fungicides are primarily used to control grapevine diseases but insecticides and herbicides are likewise used. Pesticide residues in viticultural areas currently represent a strong societal concern, but may also affect different trophic chains in such areas. In this project we wish to analyse honeybees collected from hives placed in different vineyards, their natural predator (the invasive hornet Vespa velutina), as well as the honey, grape berries, and wines produced.

Read More

A NEW STRATEGY AND METHODOLOGY FOR THE CHARACTERIZATION OF POLYPHENOLS IN FINING PRECIPITATE

Polyphenols are secondary metabolite widely distributed in plant kingdom such as in fruits, in grapes and in wine. During the winemaking process, polyphenols are extract from the skin and seed of the berries. Fining is an important winemaking step just before bottling which has an impact on wine stabilization and clarification. Most the time, fining agent are animal or vegetal protein while some of them can be synthetic polymer like PVPP or natural origin like bentonite.

Read More