Effects of sulfur dioxide on wine made with sulfitic maceration

Gabriela Victoria Jardim¹, Leticia Zigiotto¹, Wellynthon Machado and Ângela Rossi Marcon¹.

¹Unipampa- Federal University of Pampa, Campus Dom Pedrito. Street Vinte Um de Abril, 80. CEP 96450-000. RS (Brazil)

Abstract. Sulfitic maceration is part of a technique used in large companies to store must through the superdosing of
sulfur dioxide added after the destemming of the grapes. The objective of this study was to analyze the physico-
chemical characteristics of the wines elaborated by sulfitic maceration. The study was conducted at the Federal
University of Pampa (UNIPAMPA), Campus Dom Pedrito, RS, Brazil. Three vinifications (identified by treatments
1, 2 and 3) were performed with 3 replicates each. The grapes used were the cultivar Alicante Bouschet. Treatment 1
underwent the same procedures as treatment 2, except for the dosage of 1400 mg.L-1 of added sulfur dioxide. The
grapes were destemmed, crushed and macerated for 2 days and before fermentation started, the must was heated to
remove SO2. In the treatment 3 a traditional maceration was carried out for 5 days. The physicochemical
characteristics of the wines were analyzed by Fourier Transform Infrared Spectroscopy (FTIR) and the results were
analyzed by statistical analysis of comparison of averages. The color intensity of treatment 2 showed no significant
difference in relation to the treatment 3, demonstrating that with 2 days of sulphitic maceration, occurs a color
extraction similar to a traditional 5-day maceration .

1 Introduction as well as to analyze the effects of sulfur dioxide, comparing

it with a traditional maceration winemaking.
For large companies producing grape derivatives (juices,
wines, distillates and etc.) the use of grapes that have low 1.1 Sulfur dioxide in the oenological industry
sanity and little maturation makes it possible to create a
niche market where the prices of the products are more Sulphur dioxide is used in the wine industry due to its
competitive, although it is necessary to maintain a certain efficiency and durability in wine preservation. Among its
quality. Large companies also need logistics for the functions is the action against oxidation, and inhibition of
processing of all raw materials, since the availability of microorganisms [1]. Adding high doses of sulfur dioxide
tanks and equipment during the harvest is limited, because requires stainless steel tanks for proper storage, as the
the grape harvest is concentrated in 3 months of the year. product at high dosages becomes corrosive. However, due to
Thus, sulphite maceration appears as a technique that desulfation, it is possible to decrease the SO2 dose of the
facilitates the relocation of equipment and utilization of final product.
grapes with undesired quality. The sulfitic maceration is a
technique that uses after the destemming and crushing 1.2 Phenolic compounds
processes, the addition of high doses of sulfur dioxide
(between 1000 and 2000 mg.L-1 of SO2). After the high The red wines are thus named because of their coloration
dosage is made a short pre-fermentative maceration which and their structure coming from the phenolic compounds,
we call "sulphite maceration" followed by the pressing. This these are extracted mainly during the process of maceration,
technique promotes rapid extraction of phenolic compounds period in which the musts stays in contact with grape skin
without starting alcoholic fermentation for the production of Their quantity also depends on the characteristic of each
a red wine and also makes it possible to store the wort cultivar. Phenolic compounds as well as primary aroma
without the need of a cooling system. For further molecules are accumulated during maturation and are
vinification or juice preparation, the sulphited must is passed mainly concentrated in the skin of the grape. [2]
through a desulfurizer (equipment with a vacuum or steam
heat exchanger) whereby the sulfur dioxide is withdrawn 1.3 ‘Alicante Bouschet’
and the product can then be destined for the desired
purposes. As this technique uses very energetic processes The cultivar 'Alicante Bouschet' is a cultivar Vitis
such as SO2 overdosing and the heating process to eliminate vinifera known for its coloration quite a tintory, is generally
it, the study aims to analyze the physico-chemical used in Brazil to add color in red wines.
characteristics of the wine elaborated by sulfitic maceration,
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2 Materials and methods Table 1. Must: Total acidity, tartaric, malic and gluconic acid from
the must. Treatments: 1 - control treatment, with pre-fermentative
The vinifications of the study were elaborated in maceration of 2 days; 2 - sulfitic maceration of 2 days; 3 -
the experimental winery of the Federal University of Pampa traditional fermentative maceration for 5 days.
(UNIPAMPA), Campus Dom Pedrito, located in the city of
Dom Pedrito, State of Rio Grande do Sul, Brazil. The Treatments Total Tartaric Malic Gluconic
cultivar 'Alicante Bouschet' from a vineyard located in the acidity acid acid acid
wine region of the Gaúcha Campaign, on the border of
1 9,40 a* 9,23 a 9,46 a 1,36 b
Brazil and Uruguay, was used as the study model.
Three treatments were performed with 3 replicates,
2 5,10 b 2,26 b 5,70 b 5,13 a
obtaining on average 6 liters of must for each repetition. The
microvinifications were based on an average Brix of 15.4 ° 3 8,40 a 7,40 a 8,00 a 0,20 c
Brix, density of 1.0675, total sugars 128.3 mg.L-1, pH of
3.23 and total acidity of 7.63 g.L-1 tartaric acid. Treatment 1,
*The letters correspond to the statistical difference, through the
called control treatment, underwent the same procedures as
Tukey test at 5% probability
treatment 2, except for the dosage of 1400 mg.L-1 of sulfur
dioxide added in gaseous form. In these two treatments, the Among the applied treatments, there was no statistical
grapes were destemmed, crushed and macerated for 2 days, influence for the variables of density and quantity of soluble
and before fermentation started, the musts underwent SO 2 solids expressed in ºBrix in the must, therefore there was no
removal, this heating to simulate the desulphitation reached significant difference for the amount of ethanol produced in
100º C and was done in the laboratory by an open system, the wines as shown in table 2.
the procedure reduced the initial volume of musts to 40%
and therefore it was necessary to add distilled water to Table 2. Density and ºBrix of wine must and ethanol
replace the evaporated volume and then start the
Treatments: 1 - control treatment, with pre-fermentative
fermentation. The warming decreased the total SO2 of wine maceration of 2 days; 2 - sulfitic maceration of 2 days; 3-
from 1400mg.L-1 to 100mg.L-1, according to analysis done traditional fermentative maceration for 5 days.
through the Gibertini equipments. In the treatment 3 a
traditional vinification was carried out with 5 days of
maceration during the beginning of the alcoholic Treatments Density ºBrix Etanol
fermentation.
For treatments 1 and 3 were added 50mg.L-1 of 1 1,066 a 15,80 a 9,91 a
SO2 in the pre-fermentative operations. In all treatments
were added: 2 mL.HL-1 of Everzym Rouge enzyme; 20g.HL- 2 1,063 a 14,76 a 10,29 a
1
of Gesferm nutrient for yeasts; and due to low amount of
sugar, were added 34 g.L-1 sucrose. The commercial yeast 3 1,073 a 14,73 a 8,82 a
used was 522 Saccharomyces cerevisiae and at the end of
the fermentations, the physicochemical analyzes of the *The letters correspond to the statistical difference, through the
wines were performed using Fourier transform infrared Tukey test at 5% probability
spectroscopy (FTIR) and, from the results, analyzes of
variance (ANOVA) and comparisons by the Tukey test at However, when we observed the ammonia (table 3), the
5% probability. amount of nitrogenous compounds that bound to SO 2
directly influenced the availability of nutrients to the yeasts,
which explains the fermentation interruption in T2, visible
3 Results and discussion in the amount of residual sugar (table 4).
Tabela 3. Ammonia and potassium from the must.
Physicochemical analyzes of the must were made
before fermentation started, but on the same day, which Treatments: 1 - control treatment, with pre-fermentative
means that the control (T1) and sulfite (T2) treatments had maceration of 2 days; 2 - sulfitic maceration of 2 days; 3-
already undergone the heating process (desulphation traditional fermentative maceration for 5 days..
simulation). It is possible to observe, according to table 1, Treatments Ammonia Potassium
the lower total acidity, tartaric and malic acid in the
sulphited wine must (T2), due to the influence of the acid 1 90,66 a 1799,66 a
compounds binding to SO2. Heating influenced the
production of gluconic acid compared to treatment 3 (T3) 2 5,0 b 1349,66 b
that was not heated and only a traditional maceration was
done. The significant difference in T1 in relation to T2 also 3 87, 66 a 1349,66 b
demonstrates the influence of SO2 in high doses in the
production of gluconic acid. *The letters correspond to the statistical difference, through the
Tukey test at 5% probability

Regarding the color intensity, the T2 does not present

significant statistical difference in relation to the treatment
 41st OIV Congress, Uruguay 2018

3, demonstrating that with 2 days of sulfitic maceration a Aknowledgment

color extraction similar to that occurs in a traditional
maceration of 5 days occurs. Anthocyanins, responsible for the authors thankhank the Salton Winery for the
wine pigmentation, are compounds that bind to SO 2 in donation of the grapes and the must, as well as the
search of stability. [1] Sulphur dioxide, according to pH, winemaker Daiane A. Badalloti for her willingness to help
influences the color percentage of anthocyanins [3] us.
Table 4. Physicochemical analysis.
Treatments: 1 - control treatment, with pre-fermentative
maceration of 2 days; 2 - sulfitic maceration of 2 days; 3 -
traditional fermentative maceration for 5 days. References
Tr Total pH Volatil Red. Glyc Color 1. B. W. Zoecklein, K. C. Fugelsang, B. H. Gump, F. S.
* acidity acidity Sugar Nury, Análisis y Producción de Vino, EA, p.185-196
(2001).
1 13,8 a 2,78 a 0,16 a 2,03 c 6, 63 b 1,68 b 2. P. Ribéreau-Gayon, D. Dubourdieu, B. Donèche, A.
Lonvaud, Handbook of Enology: The microbiology of
2 9,53 b 3,17 a 0,23 a 4,66 a 8,06 a 3,67 a wine and vinifications, EW, v.1, ed.2, p. 246 (2006).
3. P. Ribéreau-Gayon, Y. Glories, A. Maujean, D.
3 11,76 3,08 a 0,16 a 2,70 b 6,70 b 4,79 a
Dubourdieu, Handbook of Enology: The chemistry of
ab
wine stabilization and treatments, EW, v.2, ed.2, p.152-
158 (2006).
*The letters correspond to the statistical difference, through the
Tukey test at 5% probability. Total acidity (g.L-1tartaric acid);
Volatile acidity (g.L-1 acetic acid); Glyc = Glycogen (g.L-1); Color
= 420nm + 520nm + 620nm.

Oenococcus oeni bacteria were not added for the

malolactic fermentation, the wine was left in favorable
temperature conditions after the alcoholic fermentation and
the sterilization caused by the warming of the must and the
SO2 overdose (in the case of T2) can be seen, even with no
statistical difference, T3 with traditional maceration shows
some onset of malolactic fermentation, whereas T1 and T2
do not (table 5).
Table 5. Wine: Malic acid and latic acid
Treatments: 1 - control treatment, with pre-fermentative
maceration of 2 days; 2 - sulfitic maceration of 2 days; 3 -
traditional fermentative maceration for 5 days.

Treatments Malic acid Latic acid

1 5,63 a 0,00 a

2 3,3 b 0,00 a

3 4,7 a 0,06 a

*The letters correspond to the statistical difference, through the

Tukey test at 5% probability

4 Conclusions
It can be concluded that SO2 overdosing combined with
a 2-day pre-fermentative maceration extracts similar
amounts of grape compounds compared to traditional
maceration. Sulfitic maceration, besides helping to produce
quality wines, due to the sanity state of the grape, can also
contribute to wineries with few storage tanks, since it can
reduce maceration by at least 3 days.