Macrowine 2021
IVES 9 IVES Conference Series 9 Interest and impact of PVP/PVI (Polyvinylpyrrolidone/ Polyvinylimidazole) on winemaking and final quality of wines

Interest and impact of PVP/PVI (Polyvinylpyrrolidone/ Polyvinylimidazole) on winemaking and final quality of wines

Abstract

Consumers’ health and security force authorities to limit, in wine as in others food industry products, the concentration in « dangerous » molecules. Therefore the legal limit in heavy metals keeps on decreasing. As per proof EU regulation just decrease the stain concentration in wine from 0,2 to 0,15 mg/l. Certain changes , such as sodium arsenite treatment in vines, disappearance of brass in wineries to the benefit of stainless steel, limit even more the concentration of heavy metals in wines. But the use of copper derivates in vines treatments is difficult to replace. In the case of wine and its elaboration, the problem is even more complex. Indeed, regulation forces the wine producers to control the concentration of certain heavy metals in final wines. But most of the time the measured concentration is largely under legal limit (copper < 1 mg/l) with an average of 0 à 0,2 mg/l of CU, this has the consequence to let consider the wine producers that they have no problem. Unfortunately they are wrong ! This lecture will demonstrate that a major part of musts contain a copper concentration over 0,5 mg/l. The gap between must and wine is majorly do to the alcoholic fermentation that eliminate partially copper. This high concentration has a direct impact on winemaking and final wines quality. Copper is a known antiseptic, and it can have some toxic effects on micro-organisms (this effect is strain / species dependant). This leads to fermentations problems from slugglish to suck AF or difficult MLF. In addition heavy metals have an impact that can cause over 50% of “destruction” of certain aromatic compounds of grapes such as free thiols. Copper is also taking an active part in oxidation mechanisms that forms quinones and conduct to an increase of yellow length in wines colour. It increases bitterness of wines and also limit SO2 action ( copper is trapping free fraction). As for conclude this lecture will demonstrate the interest and impact PVP/PVI (only or in formulation) during winemaking as a solution to heavy metal presence such as copper. 

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Christophe Morge*, Céline Sparrow

*SOFRALAB

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

Related articles…

Oak wood seasoning: impact on oak wood chemical composition and sensory quality of wine

Oak wood selection and maturation are essential steps in the course of barrel fabrication. Given the existence of many factors involved in the choice of raw material and in natural seasoning of oak wood, it is very difficult to determine the real impact of seasoning and selection factors on oak wood composition. A sampling was done to study the evolution of oak wood chemical composition during four seasoning steps: non matured, 12 months, 18 months and 24 months. For this sampling, three selection factors were taken into account: age, grain type and the Polyphenolic Index measured by Oakscan®. Besides extractables
(~10%), three polymers constitute the main part of oak wood: cellulose, hemicelluloses and lignins.

Read More

Using elicitors in different grape varieties. Effect over their phenolic composition

Phenolic compounds are very important in crop plants and have been the subject of a large number of studies. Three main reasons can be cited for optimizing the level of phenolic compounds in crop plants: their physiological role in plants, their technological significance for food processing, and their nutritional characteristics1 Indeed, an enormous diversity of phenolic antioxidants is found in fruits and vegetables, and their presence and roles can be affected or modified by several pre- and postharvest cultural practices and/or food processing technologies (Ruiz-García et al. 2012, Goldman et al. 1999, Tudela et al. 2002). In winegrapes, the technological importance of phenolic compounds, mainly flavonoids, is well-known.

Read More

Characterization of non-Saccharomyces yeast and its interaction with Saccharomyces cerevisiae with investigation of fermentation kinetics and aromatic composition

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.20.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...
Read More

The impact of branched chain and aromatic amino acids on fermentation kinetics and aroma biosynthesis by wine yeast Saccharomyces cerevisiae

One of the major determinants of wine quality is the aroma. Wine aroma is the human perception of the matrix of grape and yeast derived volatiles and their interaction that contribute to flavour wine. Most common are higher alcohols, ester and aldehydes. In previous studies the formation of characteristic volatile compounds have been linked to the metabolism of branched-chain and aromatic amino acids
(BCAAs) in synthetic grape must. Here we report on an investigation to assess the impact of the initial amino acid concentration on the production of aroma compounds by the industrial yeast VIN13 grown in both synthetic and real grape musts.

Read More

Evaluating South African Chenin blanc wine styles using an LC-MS screening method

Sorting Chenin blanc is one of the most important white wine cultivars in South Africa. It has received a lot of attention and accolades in the past years and more research than ever is dedicated to this versatile cultivar. According to the Chenin blanc association of South Africa, there are three recognized dry wine styles, Fresh and Fruity (FF), Rich and Ripe Unwooded
(RRU), and Rich and Ripe Wooded (RRW). They are traditionally established with the aid of expert sensory evaluation, but the cost and the (subjective) human factor are aspects to be taken into account. A more objective and possibly robust way of assessing and attributing these styles can be the use of chemical analysis.

Read More