Macrowine 2021
IVES 9 IVES Conference Series 9 Effect of plant fining agents in the must flotation process. Functional characterization

Effect of plant fining agents in the must flotation process. Functional characterization

Abstract

Flotation is one of the most used processes for clarifying white grape must after the pressing process. To date, gelatine is the more used fining agent, its action being improved when combined with bentonite and silica sol. However, in recent years, there is a growing commercial interest in replacing this animal origin protein with plant proteins, due, on the one hand, to the problems associated with allergies and, on the other hand, also thinking in the vegan wine consumers. However the efficiency of plant proteins as floculating agents are lower than gelatine and varies among them, the reason behind the different behaviour being unknown (Marchal et al., 2003; Gambuti et al., 2016; Petinelli et al., 2020). The objective of this work was to compare the flocculating efficiency of a commercial gelatine, a pure pea protein and the same pea protein chemically modified and to relate this efficiency to their amino acid composition and protein functions.The determination of the efficiency was carried out by measuring the percentage of clean must after 1 h from flotation beginning and the measuring of the absorbance at 440 nm to control the browning, while the content of amino acids and peptides was carried out by HPLC-MS. The UNIPROT database was used to obtain the protein functions associated with the peptidesThe results showed that the modified pea protein showed very similar effciency as flotation agent to that of the commercial gelatine and higher than the pure pea protein. The important structural modification made to the pea protein made it more reactive, probably due to a higher exposure of its structure and the apolar and positively charged amino acids, and to the appearance of peptides with protein functions of binding to carbohydrates and proteins, which are also present in animal protein. With these results it can be concluded that pure vegetal proteins may not have sufficientt functional properties to behave as good flocculating agents, although certain chemical modification in their structure may further simulate the behaviour shown by animal protein.

DOI:

Publication date: September 7, 2021

Issue: Macrowine 2021

Type: Article

Authors

Ana Belén Bautista-Ortín, Sonia, Albendea-Roa,  Jurado

University of Murcia,Bermúdez-Galvez, (University of Murcia) Gómez-Plaza, Encarna (University of Murcia), Mar (Agrovin S.A.), Ricardo (Agrovin, S.A.)

Contact the author

Keywords

finning, amioacids, proteins, flotation, white wine

Citation

Related articles…

High-resolution aerial thermography for water stress estimation in grapevines

Aerial thermography has emerged as a promising tool for water stress detection in grapevines, but there are still challenges associated with this technology, particularly concerning the methodology employed to extract reliable canopy temperature values. This consideration is relevant especially in vertically trained vineyards, due to the presence of multiple surfaces which are captured by drone thermal cameras with high-resolution. To test the technology and the data analysis required, a field study was conducted during the 2022-2023 season in a model vineyard with multiple scions-rootstock combinations trained on a vertical shoot-positioning (VSP) system. Additionally, three irrigation regimes were implemented to introduce variability in water stress levels.

Influence of cell-cell contact on yeast interactions and exo-metabolome

Alcoholic fermentation is the main step for winemaking, mainly performed by the yeast Saccharomyces cerevisiae. But other wine yeasts called non-Saccharomyces may contribute to alcoholic fermentation and modulate the wine aroma complexity. The recurrent problem with the use of these non-Saccharomyces yeasts is their trend to die off prematurely during alcoholic fermentation, leading to a lack of their interesting aromatic properties searched in the desired wine. This phenomenon appears to be mainly due to interactions with S. cerevisiae. These interactions are often negatives but remain unclear because of the species and strain specific response. Among the non-Saccharomyces yeasts, Lachancea thermotolerans is a wine yeast naturally found in grape must and well known as a great L-lactic acid producer and an aromatic molecules enhancer, but its behavior during alcoholic fermentation can be completely different in co-fermentation with S. cerevisiae in function of strain used.

Enological potential of red grapes: cultivars and geographic origin of vineyards

The study of technologic and phenolic maturation is very efficient to determinate quality potential of red grapes cultivars and clones under different maturity levels or geographic origins

Identification and evaluation of the winemaking sub-zones of the PDO Amyndeo winegrowing region

Context and purpose of the study. The concept of terroir encompasses the investigation of the physical environment’s influence on grapevine physiology, grape composition, and wine quality, with an emphasis on employing viticultural zoning techniques to systematically characterize and analyze terroirs.

Characterizing chemical influences of smoke on wine via novel application of 13c-labelled smoke

Smoke impact is an ongoing and growing issue for vintners across the globe, with the west coast of the U.S. and Australia being two of the largest wine industries impacted. Wine has shown to be especially sensitive to smoke exposure, often acquiring off-flavor sensory characteristics, such as “burnt rubber”, “ashy”, or other medicinal off-flavors.1 While several studies have examined the chemical composition of smoke influences on wine, some studies disagree on what compounds are having the largest impact on smell and flavor.2 This study is designed as a bottom-up approach to inventory the chemical compounds derived from smoke from a grassland-like fire that are potentially influencing wine chemical composition.