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Research Article
Received: 10 October 2023 Revised: 30 May 2024 Published online in Wiley Online Library: 12 September 2024
(wileyonlinelibrary.com) DOI 10.1002/jsfa.13876
Development of an alternative method to
quantify H
2
S: application in wine fermentation
María José Paredesaand Sergio Benavides-Valenzuelab
*
Abstract
BACKGROUND: A colorimetric method for the quantification of hydrogen sulfide (H₂S) produced in microbial fermentations was
developed using lead gelled alginate microparticles packed in glass columns. The formation of a lead sulfide complex, between
H₂S and lead ion (Pb
2+
) immobilized on the microparticles, allowed simple and accurate quantification by colorimetry.
RESULTS: The microparticle-loaded columns were calibrated and showed significant analytical sensitivity. The calibration curve
of the system showed a correlation coefficient (r
2
) of 0.995 and a detection limit of 1.29 ±0.02 ∼gL
−1
. The application of the
columns in laboratory wine fermentations was able to detect variations in H
2
S production from 10.6 to 23.5 ∼gL
−1
by increas-
ing the sugar content in the medium, and from 10.6 to 3.2 ∼gL
−1
with decreasing nitrogen content in the medium.
CONCLUSION: Validation of the proposed method was carried out by determining H₂S in a vinic fermentation model, the results
of which were compared with those obtained using a reference chemical method. The data obtained showed no statistically sig-
nificant differences between the two methods, confirming the reliability and accuracy of the developed system.
© 2024 Society of Chemical Industry.
Keywords: ionic gelation; microparticles; H
2
S; wine fermentation; colorimetric method
INTRODUCTION
Hydrogen sulfide (H
2
S) is a colorless, toxic gas. It is produced as a
by-product of anaerobic fermentation of organic matter,
1
and
although it is required in very low concentrations in cheese
and beer, it is undesirable in other foods.
2
The wine industry can
be the most affected by the production of H
2
S in fermentations,
this is because it gives the wine an unpleasant smell, like ‘rotten
eggs’.
2–4
The H
2
S perception threshold is low; in white wines, it
is 0.9–1.1 μgL
−1
,
3
while for reds it is 1.6–80 μgL
−1
, so it can be
easily perceptible.
34
The H
2
S production in wine fermentations
is due to several factors such as: sulfites in the must, environmen-
tal conditions during fermentation
2,5
(temperature, nutrients
anoxia stages, among others), and genetic characteristics of the
fermentative yeasts
2,5,6
(production of sulfite reductase, sulfite
oxidase, and sulfhydryl oxidase enzymes
2
). The ability to detect
and quantify H
2
S during wine fermentation is necessary to iden-
tify and correct the causes.
7
The routine monitoring of the winery
is often not enough to control H
2
S production, hence real-time
detection and quantification are key to help the winemaker
address the problem early.
8
In this regard, there are several
methods to quantify H
2
S,
9
such as molecular absorption
spectrometry,
10
cadmium or zinc traps,
11,12
electrochemical gal-
vanic cells,
8
fluorescence,
9
chromatography, and amperome-
try.
13-15
However, these methods require expensive instruments
and specialized personnel. Even methods that are usually accu-
rate are cumbersome to apply, such as cadmium traps; a common
colorimetric method used to measure H
2
S during fermentation.
11
This method has several disadvantages, such as time-consuming
preparations and sampling procedures, photo-oxidation of the
capture agent, interference by sulfites,
11
and loss of sulfide
through volatilization and/or oxidation.
1
Nevertheless, colorimet-
ric methods remain an alternative in which H
2
S formation can be
measured in real-time, while color intensity can be correlated with
H
2
S concentration. Traditional H₂S detection in winemaking
involves colorimetric methods using lead acetate-impregnated
materials; H₂S gas reacts with lead acetate, forming a black lead
sulfide precipitate whose height correlates with H₂S concentra-
tion. A variant of this method was established by Park,
16
who
developed a method that can quantitatively measure H
2
Sby
changing the cellulose matrix to silica crystals as a solid support
for lead acetate solutions. Both the cellulose and the silica column
can be installed at the headspace outlet of the fermenter so that
they detect gases from the fermentation process [carbon dioxide
(CO
2
), H
2
S, water, and others].
Lead sulfur capture and fixation methods although effective in
detecting the presence of H
2
S; packing and preparation of the col-
umn is a laborious task which, if not done correctly, can result in
the creation of air pockets at some points, while others are over-
loaded and heavily compacted. This results in an uneven distribu-
tion of the lead acetate within the column, which can make
*Correspondence to: S Benavides-Valenzuela, Escuela de Nutrición y Dietética,
Facultad de Ciencias para el Cuidado de la Salud, Universidad San Sebastián,
Lientur 1457 Concepción, Bio Bio region, 4030000, Chile, E-mail: sergio.
benavides@uss.cl
aDepartment of Fruticulture and Oenology, Faculty of Agriculture and Forestry,
Pontificia Universidad Católica de Chile, Santiago, Chile
bEscuela de Nutrición y Dietética, Facultad de Ciencias para el Cuidado de la
Salud, Universidad San Sebastián, Concepción, Chile
J Sci Food Agric 2025; 105: 850–857 www.soci.org © 2024 Society of Chemical Industry.
850