Page 185 - Petelin, Ana, ur. 2024. Zdravje delovno aktivnih in starejših odraslih / Health of Working-Age and Older Adults. Zbornik povzetkov z recenzijo ▪︎ Book of Abstracts. Koper: Založba Univerze na Primorskem/University of Primorska Press

Wine with less sulphur

Jurij Gunzek
School Centre Šentjur, Higher vocational school, Šentjur, Slovenia

Introduction and purpose: Sulphur dioxide is potentially the most important irritant in
wine. The ILO (International Labour Organisation) recommends avoiding sulphur di-
oxide if you suffer from bronchitis, asthma, conjunctivitis, emphysema, cardiovascu-
lar disease. According to the WHO recommendations, no more than 25 mg SO /per-
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son should be consumed daily. In wine, sulphur is defined as free and total SO . Free
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SO represents sulphur dioxide that is not bound to acetaldehyde, other aldehydes
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or organic compounds. Total SO is defined as the summary of all the species (speci-
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ation) of sulphur dioxide in wine (molecular, bisulphite and sulphite) in either free or
bound form.
Content presentation: The small proportion of sulphur dioxide in wine is result to the
action of wine yeasts in the fermentation of the must. Most of the sulphur dioxide in
wine is added during the technological process of grape processing and wine care. The
maximum levels of sulphur dioxide in wine are prescribed by wine legislation. White
and rosé wine which are containing less than 7g/l reducing sugars and defined as a pre-
mium wine may contain a maximum of 180 mg/l total SO . A premium red wine con-
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taining up to 7 g/l reducing sugars may contain a maximum of 140 mg/l total SO . For
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some time now, initiatives have been made in professional circles to lower the permit-
ted SO content in wine. These requirements will be an additional challenge for wine posterji | poster presentations
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producers, but we believe that in the future, wine with as little sulphur as possible will
be an important competitive advantage for winemakers. Modern grape processing
technologies are available to reduce sulphur use significantly.
Conclusions: Many wineries in Slovenia have invested in equipment to create reducing
conditions in wine production in recent years, also with the help of European fund-
ing. Special presses with the possibility of injecting nitrogen or carbon dioxide are
used to prevent the binding of oxygen, which inhibits the growth of micro-organ-
isms. The reduction in oxygen fixation and the consequent reduction in the need to
use sulphur is also achieved in the conditions in which wine is stored in modern con-
tainers in which inert gases (nitrogen, carbon dioxide, argon) are used to reduce oxy-
gen fixation. Recent research on physical treatment processes for wine offers interest-
ing solutions to reduce the need for sulphur. The best results have been obtained with
UHPH (Ultra High-Pressure Homogenisation) wine treatment. In this treatment, the
must is exposed to high pressures and consequently high temperatures (100 °C and
above), but for a very short time, typically 0.2 s for the whole process. The results of
the above-mentioned studies are promising, in particular because of their antimicrobi-
al and antienzymatic efficacy and very low sensory impact.
Keywords: wine, sulphur dioxide, technological process

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