Terroir 2010 banner
IVES 9 IVES Conference Series 9 Comparative studies on the dynamics of fermentation of selected wine yeasts

Comparative studies on the dynamics of fermentation of selected wine yeasts

Abstract

Alcoholic fermentation is an anaerobic biochemical process of oxidation-reduction in which carbohydrates are metabolized by the action of yeast enzymes in major products (ethylalcohol and carbon dioxide) and minor products (superior alcohols, aldehydes, acetic acid, glycerol, volatile acids and others). Typical agents of the alcoholic fermentation are from Saccharomyces genus, by fermentation resulting concentrations in ethylic alcohol higher that 8 alcoholic degrees. In this paper it was studied the dynamics of fermentation of 3 strains of Saccharomyces ellipsoideus wine yeast and were observed parameters such as the accumulation of alcohol, the release of CO2, temperature, amount of oxygen released. It was found that alcoholic fermentation depends on medium factors but also on biotechnological qualities of yeasts selected for this purpose.

DOI:

Publication date: December 3, 2021

Issue: Terroir 2010

Type: Article

Authors

Ketney Otto,Tita Ovidiu, Oprean Letitia, Tita Mihaela, Gaspar Eniko, Lengyel Ecaterina

Lucian Blaga University
Faculty of Agricultural Sciences, Food Industry and Environmental Protection, Ioan Ratiu street no.7-9
Sibiu, Romania

Contact the author

Keywords

Alcoholic fermentation, Saccharomyces cerevisie var. ellipsoideus, yeast, fermenter

Tags

IVES Conference Series | Terroir 2010

Citation

Related articles…

How to transform the odor of a white wine into a red wine? Color it red!

Does a white wine smell like red wine if you color it with red food coloring? A study by Morrot, Brochet, and Dubourdieu (2001, Brain and Language) suggests so. Subjects perceived red wine odors when tasting white wine that had been colored red. The perceived odor profile of the colored white wine became similar to that of a red wine. However, the forced-choice procedure used by Morrot et al. has some methodological shortcomings. Here, we used an alternative method (a rating procedure) to evaluate the presented wines.

First application of an original methodology created to overcome conflicts between stakeholders in an important wine-growing territory: methodology, results, and perspectives in the application of sustainability EME4.1C

Considering the previous research and activities, also, on Sustainability EME4.1C which, as widely known, considers in a harmonious chain all the factors material, immaterial, moral and spiritual related to all aspects environmental, economic, social, existential, relational, ethical, technical and “MetaEthic” indexed 4.1C

Mechanisms involved in the heating of the environment by the aerodynamic action of a wind machine to protect a vineyard against spring frost

One of the main consequences of global warming is the rise of the mean temperature. Thus, the heat summation by the plants begins sooner in the early spring, and by cumulating growing degree-days, phenological development tends to happen earlier. However, spring frost is still a recurrent phenomenon causing serious damages to buds and therefore, threatening the harvests of the winegrowers. The wind machine is a solution to protect fruit crops against spring frost that is increasingly used. It is composed of a 10-m mast with a blowing fan at its peak. By tapping into the strength of the nocturnal thermal inversion, it sweeps the crop by propelling warm air above to the ground. Thus, stratification is momentarily suppressed. Furthermore, the continuous action of the machine, alone or in synergy, or the addition of a heater allow the bud to be bathed in a warmer environment. Also, the punctual action of the tower’s warm gust reaches the bud directly at each rotation period. All these actions allow the bud to continuously warm up, but with different intensities and over a different period. Although there is evidence of the effectiveness of the wind machines, the thermal transfers involved in those mechanisms raise questions about their true nature. Field measurements based on ultrasonic anemometers and fast responding thermocouples complemented by laboratory measurements on a reduced scale model allow to characterize both the airflow produced by the wind machine and the local temperature in its vicinity. Those experiments were realized in the vineyard of Quincy, in the framework of the SICTAG project. In the future paper, we will detail the aeraulic characterization of the wind machine and the thermal effects resulting from it and we will focus on how the wind machine warms up the local atmosphere and enables to reduce the freezing risk.

Effect of mannoproteins extracted from Torulaspora delbrueckii on wine flavanol composition and on flavanol-salivary protein interactions

Global climate change is exerting an influence on vine phenology, leading to a decoupling of technological and phenolic maturity of grapes. This results in the modification of berry chemical composition, which can translate into wines with excessive astringency. The addition of mannoproteins (MP) to wine has been proposed as a way of mitigating this problem, since some studies have shown that MPs can modulate wine astringency. However, the mechanism underlying the astringency modulation effect of MPs is not well known and it seems to be dependent on the compositional and structural characteristics of the MP.

Mannoproteins extraction from wine lees using natural deep eutectic solvents

Wine lees can be a good source of yeast mannoproteins for both food and wine applications [1,2]. However, mannoprotein extraction from wine lees has not yet been scaled up to an industrial scale, mainly because of the limited cost-effectiveness ratio of the methods employed at the laboratory scale [2].