 IVES 9 IVES Conference Series 9 Biosurfactant from corn-milling industry improves the release of phenolic compounds during red winemaking

Biosurfactant from corn-milling industry improves the release of phenolic compounds during red winemaking

Abstract

AIM: Biosurfactants can be used as emulsifier agents to improve the taste, flavour, and quality of food-products with minimal health hazards [1]. They are surface-active compounds with antioxidant and solubilizing properties [2]. In this study, a biosurfactant has been evaluated during red winemaking for its effect on fermentation dynamics, phenolic compounds extraction, and colour stabilization.

METHODS: The biosurfactant used was obtained from a fermented residual stream of corn-milling industry, named corn steep liquor (CSL). The harvested mass from Merlot winegrapes was distributed in 12 fermentation flaks with the same proportion of grape juice and solid parts. Six of them were added with CSL biosurfactant (1 g/L) whereas the other six were not added (control). Two fermentation protocols were assessed (spontaneous and Saccharomyces cerevisiae inoculated). Fermentation dynamics and kinetics, standard chemical parameters, colour characteristics, and phenolic composition were determined during maceration and at the end of malolactic fermentation.

RESULTS: During inoculated maceration, the biosurfactant-added samples showed significantly higher values of total polyphenols and colour intensity when compared to control, and lower ones of the three colour CIEL*a*b* coordinates (lightness, red/green, and yellow/blue). At the end of alcoholic fermentation, a higher percentage of more stable polymerized pigments was also observed. The final wine resulted to be richer in total polyphenols and anthocyanins, as well as in high molecular weight flavanols for the biosurfactant-added samples.

CONCLUSIONS

The biosurfactant addition did not affect negatively on inoculated fermentation dynamics and influenced positively the colour stability after malolactic fermentation resulting in darker and bluish wines. No significant changes on colour properties and related compounds were observed when spontaneous fermentation was performed.

ACKNOWLEDGMENTS

This study was supported by the Spanish Ministry of Economy and Competitiveness (MINECO project RTI2018-093610-B-100)

DOI:

Publication date: September 7, 2021

Issue: Macrowine 2021

Type: Article

Authors

Susana Río Segade

University of Torino, Italy,Susana RÍO SEGADE, University of Torino, Italy Vasileios ENGLEZOS, University of Torino, Italy Alejandro LÓPEZ-PRIETO, University of Vigo, Spain Maria Alessandra PAISSONI, University of Torino, Italy Simone GIACOSA, University of Torino, Italy Kalliopi RANTSIOU, University of Torino, Italy Luca ROLLE, University of Torino, Italy Benita PÉREZ CID, University of Vigo, Spain Ana Belén MOLDES, University of Vigo, Spain Jose Manuel CRUZ, University of Vigo, Spain

Contact the author

Keywords

red grapes; winemaking; biosurfactant; fermentation dynamics; colour characteristics; phenolic compounds; polymeric pigments

Citation

Responses of grape yield and quality, soil physicochemical and microbial properties to different planting years

As an economically important fruit crop, continuous cropping of grapes can potentially impact soil health resulting in decreased yields.

Le cuivre sur raisins et moûts: dosage et intérêts de la mesure

Avec l’accroissement des surfaces viticoles conduites en Bio, la question de l’impact de la présence de résidus de cuivre (seul anti fongique autorisé dans l’UE dans ce cadre Règlementaire) sur le déroulement des fermentations et sur les qualités œnologiques et organoleptiques des vins s’est révélée de plus en plus cruciale.

Study and valorization of vineyards “terroirs” in the Val de Loire

Face à la concurrence mondiale, il est indispensable de s’orienter vers des vins de qualité, marqués par une typicité et une authenticité inimitables. Le terroir représente, pour une région donnée, un patrimoine unique et non reproductible, qui peut être valorisé à travers l’origine et les caractéristiques sensorielles du vin.

Impact on leaf morphology of Vitis vinifera L. cvs Riesling and Cabernet Sauvignon under Free Air Carbon dioxide Enrichment (FACE)

Atmospheric carbon dioxide (CO2) concentration has continuously increased since pre-industrial times from 280 ppm in 1750, and is predicted to exceed 700 ppm by the end of 21st century. For most of C3 plant species elevated CO2 (eCO2) improve photosynthetic apparatus results in an increased plant biomass production. To investigate the effects of eCO2 on morphological leaf characteristics the two Vitis vinifera L. cultivars, Riesling and Cabernet Sauvignon, grown in the Geisenheim VineyardFACE (Free Air Carbon dioxide Enrichment) system were used. The FACE site is located at Geisenheim University (49° 59′ N, 7° 57′ E, 94 m above sea level), Germany and was implemented in 2014 comparing future atmospheric CO2-concentrations (eCO2, predicted for the mid-21st century) with current ambient CO2-conditions (aCO2). Experiments were conducted under rain-fed conditions for two consecutive years (2015 and 2016). Six leaves per repetition of the CO2 treatment were sampled in the field and immediately fixed in a FAA solution (ethanol, H2O, formaldehyde and glacial acetic acid). After 24 h leaf samples were transferred and stored in an ethanol solution. Subsequently, leaf tissue was dehydrated using ethanol series and embedded in paraffin. By using a rotary microtomesections of 5 µm were prepared and fixed on microscopic slides. Subsequent the samples were stained using consecutive staining and washing solutions. Afterwards pictures of the leaf cross-sections were taken using a light microscope and consecutive measurements were conducted with an open source image software. Differences found in leaf cross-sections of the two CO2 treatments were detected for the palisade parenchyma. Leaf thickness, upper and lower epidermis and spongy parenchyma remained less affected under eCO2 conditions. The observed results within grapevine leaf tissues can provide first insights to seasonal adaptation strategies of grapevines under future elevated CO2 concentrations.

Impact of the maturity and the duration of maceration on phenolic composition and sensorial quality of Divico wines

Following its approval in 2013 by Agroscope, Divico became the first interspecific grape variety in Switzerland with high resistance to downy mildew (Plasmopara viticola) and grey rot (Botrytis cinerea), and medium resistance to powdery mildew (Uncinula nectator). Extremely riche in color, Divico grapes showed great enological potential to different styles of wine. Quickly, many wine growers were interested in planting this promising variety. Many of its potential are to be explored in the coming years.