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.

EFFECTS OF DIFFERENT PRUNING TYPES ON CHARENTE UGNI BLANC GRAPE AND WINE QUALITY

Since the use of sodium arsenite was banned in 2001, Grapevine Trunk Diseases (GTDs) have become even more widespread increasing (1).To avoid pathogen entry, pruning, an age-old practice, is increa- singly coming to the fore. As the vine is a liana (2), any excessive woody proliferation has to be stopped. This can preserve grapevine life, provided it does not damage the diaphragm.

IMPACT OF GRAPE-ASSOCIATED MOLDS IN FRESH MUSHROOM AROMA PRODUCTION

Mycobiota encountered from vine to wine is a complex and diversified ecosystem that may impact grape quality at harvest and the sensorial properties of wines, thus leading to off-flavors [1-3]. Among known off-flavors in wine, fresh mushroom aroma (FMA) has been linked to some mold species, naturally pre-sent on grapes, producing specific volatile organic compounds (VOC) [4-5]. The most well-known are 1-octen-3-ol and 1-octen-3-one, although many other VOC are likely involved. To better understand the FMA defect, biotic and abiotic factors impacting growth kinetics and VOC production of selected fungal species in must media and on grapes were studied.

ANTIOXIDANT CAPACITY OF INACTIVATED NON-SACCHAROMYCES YEASTS

The importance of the non-Saccharomyces yeasts (NSY) in winemaking has been extensively reviewed in the past for their aromatic or bioprotective capacity while, recently their antioxidant/antiradical potential has emerged under winemaking conditions. In the literature the antioxidant potential of NSY was solely explored through their capacity to improve glutathione (GSH) content during alcoholic fermen- tation [1], while more and more studies pointed out the activity of the non-glutathione soluble fraction released by yeasts [2].

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.