Macrowine 2021
IVES 9 IVES Conference Series 9 Innovations in the use of bentonite in enology: interactions with grape and wine proteins, colloids, polyphenols and aroma compounds.

Innovations in the use of bentonite in enology: interactions with grape and wine proteins, colloids, polyphenols and aroma compounds.

Abstract

The use of bentonite in oenology rounds around the limpidity and the stability that determine consumer acceptability. As a matter of fact, the haze formation in wine reduces its commercial value and makes it unacceptable for sale. Stabilization treatments are, therefore, essential to ensure a long-time limpidity and to forecast the formation of deposits in the bottle. Bentonite that is normally used in oenology for clarifying-fining purpose, shows a natural clay-based mineral structure allowing it to swell and to jelly in water and hence in must and wine. The exchangeable cations in its lamellar structures strongly influence some properties, like, for instance, the specific surface, the exchange capacity, as well as the adsorption behaviour. The interactions with haze forming proteins, other colloids, as well as aroma compounds and polyphenols would have been to discover as the modulation of wine colloids by an adjuvant severely affects the wine sensory profile. Body Oenologists do not really know on which parameters they have to focus for the choice of the bentonite targeted at gaining both the desired degree of limpidity and stability coupled with the avoiding of undesirable side effects. In this field, the authors have carried out many scientific and technical activities that led to detect: -The proteins targeted by the bentonite; -The endogenous allergenic wine compounds that are removed by bentonite; -The effect of protein origin, content, and pH toward wine colloidal (heat) stability; -The bentonite optimization for red wine fining; -The bentonite side effects on polyphenols and colour; -The interactions with the free- and glycosylated-varietal aroma in musts and wines; -The removal of fermentative aroma according to the wine aging, colloids and protein content; -The adsorption mechanism and modelling of wine aroma compounds onto bentonite. Conclusion The role of bentonite added to settling juices and/or to fining wine was not fully clear. This work collects several studies from authors focusing on the impact of several commercial bentonite samples, used for both juice clarification and wine fining, on the colloids, proteins, polyphenols and aroma compounds of white and red wines. Some parameters of practical value, such as the heat-stability of colloids, the concentration of total and haze-forming proteins, the content of the most relevant varietal and fermentative aroma were assessed to track bentonite effects and to achieve findings that are immediately applicable in the field of oenology.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Milena Lambri*, Dante Marco De Faveri, Donato Colangelo, Fabrizio Torchio

*UCSC

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

Related articles…

Influence of wood chips addition during alcoholic fermentation on wine phenolic composition

This study investigates the effect of wood chips addition during the alcoholic fermentation on the phenolic
composition of the produced wines. A series of wood chips, originating from American, French, Slavonia
oak and Acacia were added at the beginning of wine alcoholic fermentation. Besides, a mixture consisting
of 50% French and 50% Americal oak chips were added during the experimentation. The wine samples
were analyzed one month after the end of malolactic fermentation, examining various chemical
parameters such as total anthocyanins, total phenolic content, tannins combined with protein (BSA) and
ellagitannin content.

The influence of soil management practices on functional traits and biodiversity of weed communities in Swiss vineyards

Green cover in vine rows provides many ecological services, but can also negatively impact the crop, depending on the weed species. The composition of a vineyard weed community is influenced by many parameters. Ensuring an evolution of the vine row flora into a desired direction is therefore very complex. A key step towards this goal is to know which factors influence the establishment of the weed community and which types of communities are best suited for vineyards. In this study, we analysed the weed communities of several vineyards in the Lake Geneva region (379 botanical surveys on 117 plots), with the aim to highlight the links between soil management practices (chemical and mechanical weeding, mowing, mulching roll) and phytosociological profiles, biodiversity and selected functional traits (growth forms, life strategies, root depth). T

How do different oak treatment affect the sensory composition of Chenin blanc wines over time?

Wooden barrels have been the preferred method for oak maturation for wines, but the use of alternative oak products, such as staves and oak chips have increased in South Africa due to lower production costs. This study investigated the effect of different oak products used during fermentation and ageing on the sensory profile, degree of liking and perceived quality of a South African Chenin blanc wine. The different wine treatments included an unoaked tank control wine, wines matured in 5th fill barrels, wines matured in new barrels from three different cooperages, and wines matured in 5th fill barrels with stave inserts from two different cooperages.

Trans-resveratrol concentrations in wines Cabernet Sauvignon from Chile

This study evaluated the levels of trans-resveratrol in commercial wines made from Cabernet Sauvignon grapes from different valleys of Chile stilbenes. The Cabernet Sauvignon is the most planted variety in Chile, being 38% of the total vineyard country. Chile is the fourth largest wine exporter in the world, so it is important to evaluate the Cabernet-Sauvignon wines in their concentration levels of trans-resveratrol and its relation to the benefits provided to human health in moderate consumption. Evaluation comprises commercial wines from different valleys of Chile and its relationship with climatic characteristics, soil and vineyard handling.

Elicitors used as a tool to increase stilbenes in grapes and wines

The economic importance of grapevine as a crop plant makes Vitis vinífera a good model system to study the improvement of the nutraceutical properties of food products (Vezulli et al. 2007). Stilbenes in general, and trans-resveratrol in particular, have been reported to be responsible for various beneficial effects. Resveratrol´s biological properties include antibacteria and antifungal effects, as well as cardioprotective, neuroprotective and anticâncer actions (Guerrero et al. 2010 ). Stilbenes can be induced by biotic and abiotic elicitors since they are phytoalexins (Bavaresco et al. 2001).