IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Evaluation of mannoprotein formation by different yeast strains by enzymatic analysis of mannose and tribological estimation of astringency

Evaluation of mannoprotein formation by different yeast strains by enzymatic analysis of mannose and tribological estimation of astringency

Abstract

A positive role of mannoproteins on wine stability and red wine mouth sensations has been widely described. Commercial mannoproteins are available and some yeast strains are offered with a higher formation of mannoproteins. However, mannoprotein analysis is complex and its determination at cellar level is very limited. An adaptation of a relatively simple method of analysis of mannoproteins was developed, based on concentration of poly saccharides by membrane filtration, hydrolysis and enzymatic determination of mannose. The method was applied to the analysis of the mannoprotein content of wines fermented with different yeast strains deemed to produce high amounts of mannoproteins. Significant differences in mannoprotein concentration of red wines fermented with different strains was obtained. A tribological estimation of astringency also showed differences in the friction coefficient between wines. Sensory evaluation of wines using RATA (Rate all that Apply) with a panel of trained enologists showed significant differences only in some mouth parameters like dryness, grease, structure and bitter. Reasonable correlations between mannose concentration and friction coefficient were obtained only in wines coming from an earlier harvest. Correlations of mannose and friction coefficient with sensorial parameters were in general low except for dryness with friction coefficient in the early harvested wines. Even if significant, differences in mannoprotein concentration between strains were moderate, what can explain these results. Findings of this work propose an effect of mannoproteins on
sensory perception and opens the possibility to explore their effect on wine quality

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article

Authors

Bordeu Edmundo¹, Vidal Josefina¹, Vargas Sebastián², Zincker Jorge², Schober Doreen²and Brossard Natalia ¹

¹Department of Fruit Trees and Enology, Pontifical Catholic University of Chile, Santiago, Chile
²Center for Research and Innovation Concha y Toro (CII

Contact the author

Keywords

Mannoproteins, Yeast strains, RATA (Rate all that apply), Oral lubrication, Astringency

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

A new step toward the comprehensive valorisation of grape marc through subcritical water extraction of polysaccharides

Winemaking generates a significant amount of waste. Grape marc, the main solid residue, constitutes 20-25% of the pressed grapes and approximately 8-9 million tons are produced globally each year.

Read More

The key role of vineyard parcel in modifying flavor compounds of Cabernet Sauvignon grapes

To produce premium wines in a specific region is the goal of local oenologists. This study aimed to investigate the influence of soil properties on the flavoromics of Cabernet Sauvignon grapes to provide a better insight into single-vineyard wines. Six commercial Cabernet Sauvignon vineyards were selected in the Manas region to collect berries at three harvest ripeness in three seasons (2019–2021). The six vineyards had little difference in mesoclimate conditions while varying greatly in soil composition.

Read More

Accumulation of deleterious mutations in grapevine and its relationship with traits of interest for wine production and resilience

Deleterious mutations that severely reduce population fitness are rapidly removed from the gene pool by purifying selection. However, evolutionary drivers such as genetic drift brought about by demographic bottlenecks may comprise its efficacy by allowing deleterious mutations to accumulate, thereby limiting the adaptive potential of populations. Moreover, positive selection can hitchhike mildly deleterious mutations due to linkage caused by lack of recombination. Similarly, in the context of species domestication, artificial selection mimics these evolutionary processes, which can have undesirable consequences for production and resilience. In this study, we evaluated the extent of the accumulation of deleterious mutations and the magnitude of their effects (also known as genetic load) at the whole-genome scale for ca.

Read More

Grape ripening timing as a base for viticultural zoning: an agro-ecological approach

Due to the central role of the ripening timing in the evaluation of the varietal response to the environmental resources, a method to manage maturation curves has been developed. The method produces an index of veraison precocity and overcomes several methodological problems, like the visual evaluation of the veraison point and the multi-annual and multi-varieties data processing. It is based on a statistical and mathematical processing of the sugar ripening curves.

Read More

Système de Classification Climatique Multicritères (CCM) Géoviticole

Le travail concerne en premier la méthodologie de caractérisation du climat des vignobles, à l’échelle du macroclimat des régions viticoles du monde (géoviticulture). Trois indices climatiques viticoles synthétiques

Read More