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…

Physiological and growth reaction of Shiraz/101-14 Mgt to row orientation and soil water status

Advanced knowledge on grapevine row orientation is required to improve establishment, management and outcomes of vineyards on terroirs with different environmental conditions (climate, soil, topography) and in view of a future change to more extreme climatic conditions. The purpose of this study was to determine the combined effect of row orientation, plant water status and ripeness level on the physiological and viticultural reaction of Shiraz/101-14 Mgt.

Effects of mechanical leafing and deficit irrigation on Cabernet Sauvignon grown in warm climate of California

San Joaquin Valley accounts for 40% of wine grape acreage and produces 70% of wine grape in California. Fruit quality is one of most important factors which impact the economical sustainability of farming wine grapes in this region. Due to the recent drought and expected labor cost increase, the wine industry is thrilled to understand how to improve fruit quality while maintaining the yield with less water and labor input. The present study aims to study the interactive effects of mechanical leafing and deficit irrigation on yield and berry compositions of Cabernet Sauvignon grown in warm climate of California.

The effects of cane girdling on berry texture properties and the concentration of some aroma compounds in three table grape cultivars

The marketability of the table grapes is highly influenced by the consumer demand; therefore the market value of the table grapes is mainly characterized by its berry size, colour, taste and texture. Girdling could cause accumulation of several components in plants above the ringing of the phloem including clusters and resulting improved maturity. The aim of the experiments was to examine the effect of girdling on berry texture characteristics and aroma concentration.

Application of a fluorescence-based method to evaluate the ripening process and quality of Pinot Blanc grape

The chemical composition of grape berries at harvest is one of the most important factors that should be considered to produce high quality wines. Among the different chemical classes which characterize the grape juice, the polyphenolic compound, such as flavonoids, contribute to the final taste and color of wines. Recently, an innovative non-destructive method, based on chlorophyll fluorescence, was developed to estimate the phenolic maturity of red grape varieties through the evaluation of anthocyanins accumulated in the berry skin. To date, only few data are available about the application of this method on white grape varieties.

Different yield regulation strategies in semi-minimal-pruned hedge (SMPH) and impact on bunch architecture

Yields in the novel viticulture training system Semi-Minimal-Pruned Hedge (SMPH) are generally higher compared to the traditional Vertical Shoot Positioning (VSP). Excessive yields have a negative impact on the vine and wine quality, which can result in substantial losses in yield in subsequent vintages (alternate bearing) or penalties in fruit quality. Therefore yield regulation is essential. The bunch architecture in SMPH differs from VSP. Generally there is a higher amount but smaller bunches with lower single berry weights in SMPH compared to VSP.