terclim by ICS banner
IVES 9 IVES Conference Series 9 PRECISE AND SUSTAINABLE OENOLOGY THROUGH THE OPTIMIZED USE OF AD- JUVANTS: A BENTONITE-APPLIED MODEL OF STUDY TO EXPLOIT

PRECISE AND SUSTAINABLE OENOLOGY THROUGH THE OPTIMIZED USE OF AD- JUVANTS: A BENTONITE-APPLIED MODEL OF STUDY TO EXPLOIT

Abstract

As wine resilience is the result of different variables, including the wine pH and the concentration of wine components, a detailed knowledge of the relationships between the adjuvant to attain stability and the oenological medium is fundamental for process optimization and to increase wine durability till the time of consumption.

This work merges our 10-years’ studies¹ on bentonite along with information from the literature to design a study-model feasible to optimize the effects of adjuvants by maximizing the impact on targeted compounds, while minimizing the one on desirable wine components. The boosting was simply based on the frequently unintended uses of oenological adjuvants by winemakers based also on some lacking in the EU regulations, which produces jeopardized main and side-effects, as the ones by bentonite are emblematic.

Indeed, there is no EU regulated upper limit for the addition of bentonite during the winemaking process, but the International Oenological Codex establishes the properties of the oenological bentonites amending the three classes of Ca-, Na-, and Na-activated bentonite.

Our studies demonstrated that the from-bentonite enrichment in wine cations results from the clay Cation Exchange Capacity (CEC) and from the pH, ethanol content and ionic strength which also impact on the residual card-house clay structure that is an important property for deproteinization. Indeed, for the removal of hazing forming proteins (b-glucanases, thaumatin-like proteins, chitinases) clay properties as CEC, Swell Index (SI), and Specific Surface Area (SSA) as well as wine pH are more impacting than the bentonite dose.

Considering adjuvant side-effects, bentonite can remove phenolic compounds so to modify wine colour and astringency. About terpenic wines, double addition to must for clarifying and to wine for fining outlined less removal than to the solely wine treatment. Removal of aglycones by low doses and of glycosylated terpenols especially by Ca-bentonite were predicted by RSM. For the fermentative aroma compounds, adsorption intensity and capacity more depended on the characteristics of the bentonite (SSA and CEC) than on the properties of the substances: the main removal is an indirect effect of deproteinization, while a direct adsorption can be described by the Freundlich equation for only a few compounds.

 

1. Lambri M., Colangelo D., Dordoni R., Torchio F., De Faveri D.M. (2016). Innovations in the Use of Bentonite in Oenology: Interactions with Grape and Wine Proteins, Colloids, Polyphenols and Aroma Compounds, Chapter 18 in (Ed. Morata A. and Loira I., Intech Publisher) book: Grape and Wine Biotechnology. p. 381-400. ISBN 978-953-51-2692-8.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Milena Lambri*1, Roberta Dordoni1, Mario Gabrielli1

1. Department for Sustainable Food Process – DiSTAS, Università Cattolica del Sacro Cuore, Via Emilia Parmese, 84 – 20122 Piacenza (Italy)

Contact the author*

Keywords

Oenological practices, Precision oenology, Adjuvant optimization, Bentonite, Wine resi-lience

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

Influence of agrophotovoltaic on vine and must in a cool climate

The current energy crisis means that interest in agrophotovoltaics has increased significantly. The reason behind this is that the system aims to combine agricultural production with energy production. During the three-year period from 2020 to 2022, the effects of photovoltaic panels on the vine, the yield and the quality of the must were studied in Walenstadt in northern Switzerland, an area with a cool, humid climate. 65 Pinot noir vines were planted in the 160m2 study area. Because of the large edge effects, only 3 repetitions with 4 vines each could be created. A significantly lower leaf infestation by Plasmopara viticola was observed among the panels in each of the three years.

FREE TERPENE RESPONSE OF ‘MOSCATO BIANCO’ VARIETY TO GRAPE COLD STORAGE

Temperature control is crucial in wine production, starting from grape harvest to the bottled wine storage. Climate change and global warming affect the timing of grape ripening, and harvesting is often done during hot summer days, influencing berry integrity, secondary metabolites potential, enzyme and oxidation phenomena, and even fermentation kinetics. To curb this phenomenon, pre-fermentative cold storage can help preserve the grapes and possibly increase the concentration of key secondary metabolites. In this study, the effect of grape pre-fermentative cold storage was assessed on the ‘Moscato bianco’ white grape cultivar, known for its varietal terpenes (65% of free terpenes represented by linalool and its derivatives) and widely used in Piedmont (Italy) to produce Asti DOCG wines.

SENSORY PROPERTIES IMPORTANT TO AUSTRALIAN FINE WINE CONSUMER SEGMENT PERCEPTION OF CHARDONNAY WINE COMPLEXITY AND PREFERENCE

Wine complexity is considered a multidimensional yet equivocal sensory percept. This project uncovered sensory attributes Australian Chardonnay wine consumers associate with Chardonnay wine complexity
and correlations between expert and consumer perceived wine complexity and preference. A
wine consumer test examined 6 Australian Chardonnay wines of three complexity levels designated low (LC1&2), medium (MC1&2), and high (HC1&2) by an expert panel (n = 8) using a benchtop sensory task. Consumers (n = 81) rated their perceived liking using a 9-point hedonic scale; wine complexity with a 5-point scale anchored “low”, “low-medium”, “medium”, “medium-high”, and “high” and lastly, profiled the wines using Rate-All-That-Apply (RATA). Psychographic segmentation with the Fine Wine Instrument
(FWI) generated three segments; Wine Enthusiasts (WE n=29), Aspirants (ASP n=40) and No- Frills (NF n=12).

S. CEREVISIAE AND O. ŒNI BIOFILMS FOR CONTINUOUS ALCOHOLIC AND MALOLACTIC FERMENTATIONS IN WINEMAKING

Biofilms are sessile microbial communities whose lifestyle confers specific properties. They can be defined as a structured community of bacterial cells enclosed in a self-produced polymeric matrix and adherent to a surface and considered as a method of immobilisation. Immobilised microorganisms offer many advantages for industrial processes in the production of alcoholic beverages and specially increasing cell densities for a better management of fermentation rates.

TOWARDS THE SHELF-LIFE PREDICTION OF OLD CHAMPAGNE VINTAGES DEPENDING ON THE BOTTLE CAPACITY

Today, nearly one billion bottles of different sizes and capacities are aging in Champagne cellars while waiting to be put on the market. Among them, several tens of thousands of prestigious cuvees elaborated prior the 2000s are potentially concerned by prolonged aging on lees. However, when it comes to champagne tasting, dissolved CO₂ is a key compound responsible for the very much sought-after effer-vescence in glasses [1]. Yet, the slow decrease of dissolved CO₂ during prolonged aging of the most prestigious cuvees raises the issue of how long a champagne can age before it becomes unable to form CO₂ bubbles during tasting [2].