Page 153 - Zbornik_Konf_2019

https://doi.org/10.15414/2019.9788055220703

4 International Scientific Conference Abstracts Book
th
INFLUENCE OF THE FERMENTATION CONDITIONS ON THE PHENOLIC COMPOUNDS
CONTENT, ANTHOCYANINS, AND THE SPECTRAL CHARACTERISTICS
OF CABERNET SAUVIGNON WINES
Tatyana Yoncheva

Institute of Viticulture and Enology, Pleven, Bulgaria; E-mail.: t_ion@abv.bg
The wine characteristics have been determined by the variety potential and specificity,
but also by the yeast strain carrying out the alcoholic fermentation. Phenolic components and
anthocyanins play a significant role in the formation of organoleptic wine qualities, especially
of red wines. The yeasts influence the wine color primarily with the extracellular β-
glucosidase produced by them.
The objective of the study was to investigate the influence of the technological factors
yeast strain, temperature and inoculum amount of yeast culture on the variation of the total
phenolic substances and anthocyanins during the alcohol fermentation and on the spectral
characteristics of Cabernet Sauvignon wines.
The experiment was carried out with grapes of Cabernet Sauvignon variety with sugars
3
content of 23.10 % and titratable acids of 6.15 g/dm . The alcoholic fermentation was
conducted with inoculum amount of yeast culture 2 %, 3 %, 4 % of the Bordeaux and 8‐11
strains of Saccharomyces cerevisiae species and fermentation temperature 20 °C, 24 °C, 28 °C.
The course of the process was followed by the variation in the dry matter, measured daily with
the Abbe refractometer. The dynamics of the total phenolic compounds content and
anthocyanins during the fermentation was determined by measuring on 1 , 5 , 10 and 20
th
th
st
th
day. After the alcoholic and the malolactic fermentations in the experimental wines were also
analyzed the content of flavonoid phenolic compounds, non-flavonoid phenolic compounds,
and their spectral characteristics.
The results demonstrated that under the experimental conditions both strains Bordeaux
and 8‐11 exhibited the best fermentation activity at 28 °C. The temperature factor had a
stronger impact on the variations of total phenolic compounds and anthocyanins in the course
of the alcoholic fermentation. The quantitative maximum of both indicators was recorded on
the 5 day of the process. In the experimental wines, the variants fermented under the
th
conditions of 28 °C/4 % contained more total phenolic compounds, anthocyanins, flavonoid
phenolic compounds, non-flavonoid phenolic compounds, and the red color ratio was the
highest. The wines of 8‐11 strain were distinguished by a higher total phenolic compounds
content, anthocyanins and, respectively, more intense color.
Keywords: wine, yeast, alcoholic fermentation, phenolic compounds, spectral characteristics.

4 International Scientific Conference Agrobiodiversity Nutrition, Health and Quality of Human and Bees Life |153
th
September 11–13, 2019