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Infuence of inoculation with Malolactic bacteria on volatile phenols in wines

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Abstract

Malolactic fermentation (MLF) can help to preserve the quality of wine by hampering the development of Brettanomyces yeast. Wines that underwent MLF inhibited the growth of Brettanomyces, resulting in a product containing little or no volatile phenols. Wines that did not undergo MLF allowed proliferation of Brettanomyces, resulting in a product containing more volatile phenols. This phenomenon was seen in the laboratory and in the cellar. Wines in which the MLF did not occur showed Brettanomyces growth. Early inoculation of wine with malolactic bacteria may be a tool for lowering the risk of volatile phenol production. Copyright © 2009 by the American Society for Enology and Viticulture. All rights reserved.

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... Si les méthodes de prévention ne sont pas suffisantes pour empêcher les contaminations, des procédés peuvent être utilisés pour l'éliminer du procédé de vinification pour éviter l'altération du vin (Pinto et al., 2020;Stadler and Fischer, 2020;Suárez et al., 2007;. Ainsi, l'utilisation de « starters » (levures et/ou bactéries lactiques) pour réaliser les fermentations est un moyen de prévention particulièrement adapté (Berbegal et al., 2018;Gerbaux et al., 2009). De plus, le choix des souches utilisées dans ces « starters » a son importance. ...
... Candida pyralidae CpKT1, CpKT2 Mehlomakulu et al., 2014 Kluyveromyces wickerhamii Kwkt Comitini et al., 2004;Comitini and Ciani, 2011 Pichia anomala Pikt Comitini et al., 2004 Pichia membranifaciens PMTK2 Santos et al., 2009 Torulaspora delbrueckii TdKT Villalba et al., 2016 Wickerhamomyces anomalus KTCf20, WA18 Comitini et al., 2020;Fernández de Ullivarri et al., 2018 En parallèle, il est recommandé d'effectuer régulièrement des analyses microbiologiques afin de détecter de potentielles contaminations par B. bruxellensis (Tableau 4) (Tubia et al., 2018b). Les méthodes classiques de détection de B. bruxellensis consistent en l'utilisation de milieux de croissance sélectifs, qui mettent en évidence des traits spécifiques de cette espèce : acidification (virage de l'indicateur coloré), synthèse de phénols volatils (odeur caractéristique) ou bien résistance à la actidione/cycloheximide (Gerbaux et al., 2009;Rodrigues et al., 2001). (Agnolucci et al., 2014(Agnolucci et al., , 2010Avramova et al., 2018b;du Toit et al., 2005;G-Poblete et al., 2020;Longin et al., 2016a;Louw et al., 2016;Vigentini et al., 2013;. ...
Thesis
La gestion des contaminations par la levure d’altération Brettanomyces bruxellensis est un véritable défi pour la filière viti-vinicole. Le mode de vie biofilm, connu pour accroitre la résistance des micro-organismes et permettre leur persistance dans l’environnement, est une stratégie pouvant être adoptée par B. bruxellensis.Dans ce projet de thèse, des observations microscopiques ont permis de mettre en évidence la présence de matrice autour des cellules, un élément essentiel de la définition d’un biofilm. L’étude a également révélé que différents morphotypes sont impliqués dans la structure du biofilm, en particulier des filaments formant un véritable réseau. Des chlamydospore-like jusque-là jamais décrites chez l’espèce B. bruxellensis, ont été observées au sein du biofilm mais également dans des cultures planctoniques. La production de tels éléments pourrait être une stratégie de la levure pour mieux persister dans les environnements stressants. Des différences notables dans la quantité de cellules adhérées ont été observées en fonction de la nature des supports et des milieux utilisés, démontrant l’impact de l’environnement sur la formation de biofilm chez B. bruxellensis. En particulier, l’absence de glucose semble diminuer la capacité d’adhésion de plusieurs souches de B. bruxellensis.De plus, l’invasion de gélose chez B. bruxellensis nouvellement décrite au cours de ce travail se caractérise par le développement de structures multicellulaires diverses à l’intérieur du milieu gélosé, composées notamment de filaments. L’analyse optimisée à travers un pipeline d’acquisition et de traitement d’images révèle que la présence de glucose et d’oxygène favorise l’invasion de gélose. B. bruxellensis semble également capable de former des structures biofilm-like telles que des biofilms air-liquide et des colonies complexes.Enfin, les capacités d’adhésion, de formation de biofilm et d’invasion semblent souche dépendantes, étayant les connaissances à propos de l’importante diversité intraspécifique chez B. bruxellensis. Deux méthodologies rapides et fiables ont été adaptées afin de discriminer des souches au sein de groupes génétiques précédemment définis : un protocole de RAPD-PCR et un outil de deep learning. Ce dernier se base sur la diversité de morphologie cellulaire pour prédire le groupe génétique d’un isolat avec une précision de 96,6%. Cette approche nouvelle ouvre la voie pour la mise en place de méthodes de routine simples et accessibles aux acteurs de la filière viti-vinicole pour la prévention des risques de contamination par B. bruxellensis.
... Some studies showed that wines that underwent rapid MLF inhibited the growth of Brettanomyces, resulting in a product containing little or no volatile phenols. Conversely, wines that did not undergo MLF or underwent late spontaneous MLF that proceeded slowly allowed the proliferation of Brettanomyces, resulting in a product containing more volatile phenols [86,87]. The abovementioned OIV resolution [19] attests that if MLF is delayed, the risk of production of volatile phenols increases because Brettanomyces can take advantage of the time between alcoholic and malolactic fermentations to multiply, benefiting from the absence of SO 2 . ...
... Thus, the use of malolactic starters is proposed as a good way to limit Brettanomyces development and volatile phenol production. Co-inoculation or early sequential inoculation is presented as the best tool to prevent Brettanomyces contamination by reducing the lag phase between AF and MLF, as also shown in scientific studies [86,88]. ...
Article
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In agriculture, the wine sector is one of the industries most affected by the sustainability issue. It is responsible for about 0.3% of annual global greenhouse gas emissions from anthropogenic activities. Sustainability in vitiviniculture was firstly linked to vineyard management, where the use of fertilizers, pesticides and heavy metals is a major concern. More recently, the contribution of winemaking, from grape harvest to bottling, has also been considered. Several cellar processes could be improved for reducing the environmental impact of the whole chain, including microbe-driven transformations. This paper reviews the potential of microorganisms and interactions thereof as a natural, environmentally friendly tool to improve the sustainability aspects of winemaking, all along the production chain. The main phases identified as potentially interesting for exploiting microbial activities to lower inputs are: (i) pre-fermentative stages, (ii) alcoholic fermentation, (iii) stage between alcoholic and malolactic fermentation, (iv) malolactic fermentation, (v) stabilization and spoilage risk management, and (vi) by-products and wastewater treatment. The presence of proper yeast or bacterial strains, the management and timing of inoculation of starter cultures, and some appropriate technological modifications that favor selected microbial activities can lead to several positive effects, including (among other) energy savings, reduction of chemical additives such as sulfites, and reuse of certain residues.
... Higher volatile phenol production is proposed to be due to libration of HCAs during MLF [29]. However, on the contrary, MLF step has been reported to preserve wine quality by hampering the development of Brettanomyces [30]. According to these authors, wine underwent MLF inhibited growth of Brettanomyces, resulting to the wine that contains no or very little volatile phenols in wine. ...
... According to these authors, wine underwent MLF inhibited growth of Brettanomyces, resulting to the wine that contains no or very little volatile phenols in wine. Moreover, wines that did not undergo MLF allowed proliferation of Brettanomyces, resulted in volatile phenol containing wines [30]. Since no other clear explanation on MLF effect on Brettanomyces growth in wine has been given yet, further studies are required to understand the role of MLF in 4-EP production. ...
Article
Full-text available
Three red grapevine varieties, Touriga Nacional, Syrah and Cabernet Sauvignon, were evaluated for their susceptibility to spoilage by two strains of Brettanomyces bruxellensis during grape juice fermentation and in finished wine. B. bruxellensis ISA 2211 survived well during both alcoholic and malolactic fermentations. The 4-ethylphenol concentration at the end of malolactic fermentation was 176 µg L−1 for T. Nacional, 190 µg L−1 for C. Sauvignon and 149 µg L−1 for Syrah. These levels were slightly increased during 3 months of incubation, even though no culturable cells of B. bruxellensis could be detected after malolactic fermentation. However, a viable but non-culturable (VBNC) population of 3–4 log cells mL−1 was observed in all grape varieties when analyzed by flow cytometry. On the other hand, commercial varietal wines, inoculated with of B. bruxellensis ISA 1791, could attain levels of 6–8 log CFU mL−1 and 4-ethylphenol reached 1750, 1512 and 2707 µg L−1 in T. Nacional, C. Sauvignon and Syrah, respectively. Overall, the production of 4-ethylphenol was mostly dependent on the existence of growing B. bruxellensis populations, regardless of the grape variety. In finished wines, 4-ethylphenol was always produced in concentrations far above its preference threshold, indicating that T. Nacional, Syrah and C. Sauvignon are equally susceptible to the “horse sweat” taint.
... Some studies showed that wines that underwent MLF inhibited the growth of Brettanomyces, resulting in a product containing little or no volatile phenols. Wines that did not undergo MLF or that underwent late spontaneous MLF that proceeded slowly allowed proliferation of Brettanomyces, resulting in a product containing more volatile phenols (Gerbaux et al., 2009;Nardi et al., 2014). Thus, early inoculation of wine with malolactic bacteria may be a tool for lowering the risk of volatile phenol production. ...
... Thus, the use of malolactic starters is proposed as a good way to limit Brettanomyces development. Moreover, co-inoculation or early sequential inoculation is presented as the best tool to prevent Brettanomyces contamination by reducing the lag phase in between AF and MLF, as shown in scientific studies (Coulon et al., 2010;Gerbaux et al., 2009). After malolactic fermentation, it is recommended to eliminate all microorganisms-particularly by adding SO 2 . ...
Chapter
https://www.crcpress.com/Post-Fermentation-and--Distillation-Technology-Stabilization-Aging-and/Bordiga/p/book/9781498778695
... Culturas starters ou culturas iniciadoras de fermentação consistem na seleção de microrganismos de alimentos com atividade metabólica estável e conhecida, portadores de outras características usadas para produzir alimentos e bebidas fermentadas de aparência, corpo, textura e sabor desejáveis (RaY, 2004). atualmente esse termo abrange as formas de microrganismos fermentadores inoculados ao meio também com função protetora contra espécies contaminantes (GeRBaUX et al., 2009). o processo fermentativo em vinhos é caracterizado por uma transformação complexa do mosto da uva, pela presença de fungos filamentosos, leveduras e bactérias ácido lácticas que utilizam os açúcares fermentescíveis e outros compostos derivados a partir desse processo para elaborar o vinho. ...
... em relação aos estudos de requerimentos nutricionais das bactérias malolácticas, fontes de carbono, nitrogênio, fosfato, manganês, aminoácidos e vitaminas são nutrientes comuns para Oenococci e Lactobacilli. a partir disso, um meio quimicamente definido foi elaborado composto de 44 constituintes para prover um meio de cultura adequado a testes laboratoriais, com sucesso em 22 cepas dentre Oenococcus, Lactobacillus e Pediococcus, permitindo variações protocolares, a exemplo de uma riboflavina que pode favorecer as cepas de O. oeni (teRRaDe;oRDUÑa, 2009;teRRaDe et al., 2009 Um outro estudo mais específico, envolvendo bactérias do vinho e fenóis, avalia a influência da inoculação das culturas iniciadoras de fermentação maloláctica, em laboratório e em adega, impedindo o desenvolvimento de leveduras Brettanomyces, que são consideradas contaminantes por alterar a composição do vinho, produzindo fenóis voláteis ( GeRBaUX et al., 2009). o potencial de biodeacidificação do vinho é também estudado com leveduras transgênicas para realizar a fermentação maloláctica. ...
Article
Este artigo apresenta uma revisão bibliográfica a respeito das culturas iniciadoras de fermentação em vinhos. Fez-se uma abordagem a partir dos últimos cinco anos de pesquisa em temáticas pertinentes às áreas de Microbiologia, Biotecnologia, Ciências de Alimentos e Enologia com culturas iniciadoras. Foram revisados os processos de fermentação alcoólica, maloláctica, mista, bem como os métodos de estudo, com destaque para a Biotecnologia e as perspectivas de estudos. Palavras-chave: Culturas iniciadoras. Fermentação alcoólica. Fermentação maloláctica. Culturas mistas. Biotecnologia.
... Early inoculation with LAB after AF has been suggested as a useful way to control the proliferation of B. bruxellensis. Investigations from Gerbaux et al. (2009) showed that MLF began much sooner in Pinot Noir wines inoculated with two different wine bacteria, which contributed to a shorter duration for the winemaking process and significantly reduced the concentrations of volatile phenols (Gerbaux et al. 2009). Moreover, the inoculation of selected wine bacteria at the beginning of the AF is a solution to shorten the time-lapse between AF and MLF and thereby prevent the development of B. bruxellensis. ...
... Early inoculation with LAB after AF has been suggested as a useful way to control the proliferation of B. bruxellensis. Investigations from Gerbaux et al. (2009) showed that MLF began much sooner in Pinot Noir wines inoculated with two different wine bacteria, which contributed to a shorter duration for the winemaking process and significantly reduced the concentrations of volatile phenols (Gerbaux et al. 2009). Moreover, the inoculation of selected wine bacteria at the beginning of the AF is a solution to shorten the time-lapse between AF and MLF and thereby prevent the development of B. bruxellensis. ...
Article
Full-text available
Brettanomyces bruxellensis is a common and significant wine spoilage microorganism. B. bruxellensis strains generally detain the molecular basis to produce compounds that are detrimental for the organoleptic quality of the wine, including some classes of volatile phenols that derive from the sequential bioconversion of specific hydroxycinnamic acids such as ferulate and p-coumarate. Although B. bruxellensis can be detected at any stage of the winemaking process, it is typically isolated at the end of the alcoholic fermentation (AF), before the staring of the spontaneous malolactic fermentation (MLF) or during barrel aging. For this reason, the endemic diffusion of B. bruxellensis leads to consistent economic losses in the wine industry. Considering the interest in reducing sulfur dioxide use during winemaking, in recent years, biological alternatives, such as the use of tailored selected yeast and bacterial strains inoculated to promote AF and MLF, are actively sought as biocontrol agents to avoid the “Bretta” character in wines. Here, we review the importance of dedicated characterization and selection of starter cultures for AF and MLF in wine, in order to reduce or prevent both growth of B. bruxellensis and its production of volatile phenols in the matrix.
... The use of co-inoculation to terminate MLF faster with respect to traditional winemaking can help protect the wine from spoilage and save time. GERBAUX et al. (2009) observed that early inoculation of wine with malolactic bacteria may be a way to reduce the risk of volatile phenol production by Brettanomyces. ...
Article
Full-text available
The practice of inoculating selected bacteria before alcoholic fermentation (AF) (co-inoculation) to induce malolactic fermentation (MLF) was used to produce red table wines from several grape varieties. In most of the microvinification trials, MLF was completed before or within one week af-ter de-vatting. The acetic acid content remained within an acceptable level (<0.60 g/L). In an in-dustrial vinification (200 hL), MLF induced by co-inoculation was completed before de-vatting, while in the wines inoculated after AF, the total malic acid degradation was obtained 33 days later. The potential risk of increasing the volatile acidity was also evaluated by inducing MLF in partial-ly fermented wines. The co-inoculation practice was compatible with the production of red wines. The decrease in vinification time with respect to traditional MLF management could offer a signif-icant advantage for industrial wineries.
... In this case, the interactions between the chosen yeasts and bacteria must be taken into account, so the control of a low pH level [28,[43][44][45][46][47][48]. Some researchers advise an earlier inoculation (before the total ending of the AF), because the bigger amount of free sulphur dioxide combining with the carbonilic compounds coming from the yeasts growing phase, and the lower alcoholic content (non reaching toxic levels) would suppose an important advantage [49]. When the metabolism of the sugars has not finished, different compounds produced by the yeasts reach their maximum level, so the main problem of the earlier inoculation of the bacteria is the possible existence of an inhibitory effect of the metabolites from the yeasts on them [50]. ...
Article
Full-text available
Malolactic fermentation of wines involves not only the conversion of malate into lactate, but also several biotransformations in the wine composition that can affect positively the sensory characteristics of the wine. This secondary fermentation is held by lactic acid bacteria coming naturally from the grapes, although the wine composition not always constitutes the best medium for the lactic acid bacteria development. Nowadays, because of the climate change, the conditions are getting worse for the growing and metabolism of these bacteria: the increasing of the alcoholic content and the reduction of the nutrient content of the wines make life quite difficult for these microorganisms. For this reason, several strategies are being developed in order to enhance the wine malolactic fermentation, most of them focussing in the bacteria themselves. This document deals about the different biotechnological ways that are being used to try to solve this oenological problem.
... ods (Alexandre et al., 2004), which increases the risk of spoilage by other wine microorganisms like Brettanomyces spp. (Gerbaux et al., 2009). The compatibility of selected strains of S. cerevisiae and O. oeni has also been taken into account to improve the occurrence of sequential malolactic fermentations in a safe, predictable way (Arnink and Henick-Kling, 2005;Patynowski et al., 2002) . ...
Article
Full-text available
Interactions between yeasts and lactic acid bacteria are strain specific, and their outcome is expected to change in simultaneous alcoholic - malolactic fermentations from the pattern observed in successive fermentations. One Oenococcus oeni strain Lalvin VP41™ was inoculated with two Saccharomyces cerevisiae strains either simultaneously, three days after the yeast inoculation, or when alcoholic fermentation was close to finish. Early bacterial inoculations with each yeast strain allowed for the growth of the bacterial populations, and the length of malolactic fermentation was reduced to six days. Alcoholic fermentation by Lalvin ICV D80® yeast strain left the highest residual sugar, suggesting a negative effect of the bacterial growth and malolactic activity on its performance. In sequential inoculations the bacterial populations did not show actual growth with either yeast strain. In this strategy, both yeast strains finished the alcoholic fermentations, and malolactic fermentations took longer to finish. Lalvin ICV D80® allowed for higher viability and activity of the bacterial strain than Fermicru UY4® under the three inoculation strategies. This was beneficial for the sequential completion of both fermentations, but negatively affected the completion of alcoholic fermentation by Lalvin ICV D80® in the early bacteria additions. Conversely, Fermicru UY4®, which was rather inhibitory towards the bacteria, favored the timely completion of both fermentations simultaneously. As bacteria in early inoculations with low or no SO2 addition can be expected to multiply and interact with fermenting yeasts, not only are the yeast-bacterium strains combination and time point of the inoculation to be considered, but also the amount of bacteria inoculated.
... Since arginine and other amino acids promote the anaerobic growth of Dekkera bruxellensis (Blomqvist et al., 2012), their depletion by the growth of wine LAB during MLF could have inhibitory effects on spoilage yeasts. This fact is congruent with Gerbaux et al. (2009) that observed as wines in which the MLF did not occur showed increase of volatile phenols. Although lactobacilli such as L. hilgardii and L. buchneri, that include spoilage strains, seem to have lower nutrient requirements than O. oeni (Terrade and Mira de Orduña, 2009), the prior depletion of some essential amino acids due the activity of the latter, possibly added as a starter culture, could reduce the risk of subsequent contamination avoiding negative sensory effects. ...
Article
In the last two decades knowledge on lactic acid bacteria (LAB) associated with wine has increased considerably. Investigations on genetic and biochemistry of species involved in malolactic fermentation, such as Oenococcus oeni and of Lactobacillus have enabled a better understand of their role in aroma modification and microbial stability of wine. In particular, the use of molecular techniques has provided evidence on the high diversity at species and strain level, thus improving the knowledge on wine LAB taxonomy and ecology. These tools demonstrated to also be useful to detect strains with potential desirable or undesirable traits for winemaking purposes. At the same time, advances on the enzymatic properties of wine LAB responsible for the development of wine aroma molecules have been undertaken. Interestingly, it has highlighted the high intraspecific variability of enzymatic activities such as glucosidase, esterase, proteases and those related to citrate metabolism within the wine LAB species. This genetic and biochemistry diversity that characterizes wine LAB populations can generate a wide spectrum of wine sensory outcomes. This review examines some of these interesting aspects as a way to elucidate the link between LAB diversity with wine aroma and flavour. In particular, the correlation between inter- and intra-species diversity and bacterial metabolic traits that affect the organoleptic properties of wines is highlighted with emphasis on the importance of enzymatic potential of bacteria for the selection of starter cultures to control MLF and to enhance wine aroma.
... Moreover, it is now well known that co-inoculation reduces the total fermentation time (Rosi et al., 2006;Jussier et al., 2006;Massera et al., 2009;Abrahamse & Bartowsky, 2012;Knoll et al., 2012;Pan et al., 2011). This reduction limits the risk of spoilage by other microorganisms, such as the Brettanomyces species, which are mainly responsible for 4-ethylphenol production (Jussier et al., 2006;Curtin et al., 2007;Gerbaux et al., 2009). In addition, the thermoregulation time in the tanks can be reduced, thereby decreasing the wineries' energy costs. ...
Article
Full-text available
The present work reports the impact of yeast/LAB co-inoculation on the aromatic proffle of Merlot wines made in wineries. This study was carried out over two consecutive years on five Merlot wines in Bordeaux and Swiss wineries, using Saccharomyces cerevisiae and Oenococcus oeni starter cultures. Seventy aromatic compounds were quantified and, in addition, the sensory proffles of two wines were determined in order to compare the aromatic notes of the sequential and co-inoculated wines. The influence of the timing of inoculation with lactic acid bacteria (LAB) on the metabolic proffle of wines was observed. It confirmed previous work carried out on a micro-scale but, for the first time, the impact of yeast/LAB co-inoculation was significantly demonstrated from a sensory point of view under winery conditions. In particular, the fruity and lactic notes, as well as the markers associated with these descriptors, such as esters and diacetyl, were altered. Co-inoculation does not always favour fruity expression, nor does it reduce the diacetyl content and lactic aroma intensity. All of the trends were observed either in the production and degradation of metabolites, or by the development of an aromatic mask over the short and long term.
... Of the group of volatile phenols, ethyl phenols are particularly important because they contribute negatively to the final quality of wine, being responsible for the 'phenolic', 'animal' and 'stable' off-odours found in certain red wines (Gerbaux et al., 2009). Results from this study displayed significantly lower concentrations of 4-vinyl-guaiacol and 4-vinylphenol (precursors of ethyl phenols) in wines produced by co-inoculation, in concordance with Izquierdo Can˜as et al. (2012). ...
Article
A study has been carried out in order to determine the effect of the lactic acid bacteria inoculation time on the kinetic of vinification and on chemical and sensory characteristics of Cabernet Franc wines. Traditional vinifications, with lactic acid bacteria inoculated after completion of alcoholic fermentation were compared with vinifications where yeast and bacteria were co-inoculated at the beginning of vinification. One commercial yeast strain and an autochthonous Oenococcus oeni strain (C22L9), previously identified and selected at our laboratory, were used. Monitoring of alcoholic and malolactic fermentations was carried out by yeast and lactic acid bacteria counts and by measuring l-malic acid concentration. Wines were chemically characterized and analysed for volatile compounds content. A sensory analysis, consisting of a descriptive and a triangular test, was also carried out. Results from this study showed that the concurrent yeast/bacteria inoculation of musts at the beginning of vinification produced a reduction in duration of the process without an excessive increase in volatile acidity. Differences in volatile compounds content and the corresponding impact on the sensorial profile of wines were also displayed. These results suggest that co-inoculation is a worthwhile alternative for winemaking of Cabernet Franc wines, if compared with traditional post-alcoholic fermentation lactic acid bacteria inoculation.
... However, sequential inoculations of LAB starter pose risks: MLF can be sluggish due to the elevated ethanol concentration and to the low pH of wine (Massera, Soria, Catania, Krieger, & Combina, 2009). Moreover, with sequential inoculation the antibacterial action of SO 2 is limited because of the decreased addition of this preservative at the end of the alcoholic fermentation (Alexandre, Costello, Remize, Guzzo, & Guilloux-Benatier, 2004), thus increasing the possibility for microorganisms such as Brettanomyces spp. to spoil the produced wine (Di Toro et al., 2015;Gerbaux, Briffox, Dumont, & Krieger, 2009). Therefore, early inoculation of a LAB starter together with yeast directly into the must, in order to stimulate a simultaneous MLF and AF, has been suggested to overcome these problems and to speed up wine production by reducing the time requested for MLF completion (Azzolini, Tosi, Vagnoli, Krieger, & Zapparoli, 2010;Izquierdo Cañas, P erez-Martín, García Romero, Seseña Prieto, & Palop Herreros, 2012;Zapparoli et al., 2009). ...
Article
Traditional vinification process is undertaken with the inoculation of the lactic acid bacteria (LAB) at the end of alcoholic fermentation (AF) to induce malolactic fermentation (MLF). MLF is an important phase during winemaking and the LAB co-inoculation with yeast starter represents a promising approach to enhance the quality and safety of wine. In this investigation we have studied: i) the effect of timing of LAB inoculation on the vinification dynamics and chemical features of Negroamaro wines; ii) the interactions between two commercial yeast and two commercial Oenococcus oeni strains. The fermentations dynamics were monitored by microbial counts, quantifying l-malic acid concentration and analyzing the volatile compounds contents in the obtained wines. Our results indicate that simultaneous yeasts/bacteria inoculation at the beginning of vinification reduces the processes duration and simultaneously lowers of volatile acidity. Wine obtained after co-inoculum showed a profile dominated by red and ripe fruits notes associated to esters and to buttery and creamy notes linked to diethyl succinate and ethyl lactate. Furthermore, compatibility specification between commercial yeasts and LAB strains were observed, suggesting the importance of the assessment of microbial-compatibility before their utilization in large-scale vinification.
... Culturas starters ou culturas iniciadoras de fermentação consistem na seleção de microrganismos de alimentos com atividade metabólica estável e conhecida, portadores de outras características usadas para produzir alimentos e bebidas fermentadas de aparência, corpo, textura e sabor desejáveis (RaY, 2004). atualmente esse termo abrange as formas de microrganismos fermentadores inoculados ao meio também com função protetora contra espécies contaminantes (GeRBaUX et al., 2009). o processo fermentativo em vinhos é caracterizado por uma transformação complexa do mosto da uva, pela presença de fungos filamentosos, leveduras e bactérias ácido lácticas que utilizam os açúcares fermentescíveis e outros compostos derivados a partir desse processo para elaborar o vinho. ...
Article
Full-text available
This article presents a review about wine starters cultures. It makes a report in recent 5 years of researches about starters cultures in the follow areas: Microbiology, Biotechnology, Food Science and Enology. It was reviewed winemaking fermentations and mixed cultures as well as methodologies in the domain of Biotechnological data and the studies perpectives. Keywords: Starter culture. Alcoholic Fermentation. Malolactic Fermentantion. Mixed Culture. Biotechnology.
... Of the group of volatile phenols, ethyl-phenols are particularly important because they contribute negatively to the final quality of wine, being responsible for the 'phenolic', 'animal' and 'stable' off-odours found in certain red wines (Couto et al., 2006;Gerbaux et al., 2009;Nelson, 2008). This study shows differences, statistically significant in some cases, in the concentrations of some of these compounds in wines produced by COI or SEQ, although their behaviour differed depending on the grape variety. ...
Article
A study was carried out to determine the effect of the inoculation time of the lactic acid bacteria (LAB) on the kinetic of vinification and on chemical and sensory characteristics of Tempranillo and Merlot wines. Traditional vinifications, with LAB inoculated after completion of AF, were compared with vinifications where yeast and bacteria were co-inoculated. Two commercial yeast strains and an autochthonous Oenococcus oeni strain (C22L9) previously identified and selected at our laboratory were used. Monitoring of alcoholic and malolactic fermentations was carried out by yeast and lactic acid bacteria counts and by measuring contents of glucose+fructose, malic acid and lactic acid. The implantation rate of O. oeni C22L9 was calculated by typing isolates obtained from count plates using the RAPD-PCR (Randomly Amplified Polymorphic DNA-Polymerase Chain Reaction) technique. Wines were chemically characterised and analysed for biogenic amine and volatile compound contents. A sensory analysis, consisting in a descriptive and a triangular test was also carried out. Results from this study showed that for both grape varieties, the concurrent yeast/bacteria inoculation of musts produced a significant reduction in duration of the process, without a pronounced degradation of malic acid during AF, nor an excessive increase in volatile acidity. Biogenic amine content was also lower in wines produced by co-inoculation. Important differences in volatile compound contents were observed, although there was little impact on the sensorial profile of wines. These results suggest that co-inoculation using O. oeni C22L9 is a worthwhile alternative compared to traditional post AF inoculation for Tempranillo and Merlot winemaking.
... Therefore, the fruity character of the wines was preserved. Volatile phenols are a large family of compounds that participate in wine aroma, supplying very varied aromas (Zamora, 2003;Gerbaux et al., 2009). Different studies have determined the capacity of certain LAB to produce volatile phenols (Couto et al., 2006;Nelson, 2008), including ethylphenols. ...
Article
The behaviour in malolactic fermentation (MLF) of an autochthonous strain of Oenococcus oen4 C22L9, isolated from a winery in Castifia-La Mancha (Spain), and of two other commercial strains of 0. oeni, PN4 and Alpha (Lallemand Inc.), inoculated by direct inoculation (MBR®) and after a short accimatisation phase (1-STEP®), was studied. Strain C22L9 carried out MLF slightly faster than the two other commercial strains, leading to a lower increase in volatile acidity and in 2,3-butanedione and 3-hydroxy-2-butanone concentrations, a higher lactic acid content, lower degradation of citric acid and increased degradation of ethanoL No great differences were observed in the duration of MLF, although the accilmatisation cultures were slightly faster, or in the composition of the wines when using the 0. oeni strains in the form of MBR® or 1-STEP® cultures. The tasters did not detect significant differences in the wines obtained from the same strain of 0. oeni in the two inoculation formats.
... Co-inoculation approach has several clear benefits compared to the sequential inoculation, since the introduction of LAB inoculum before AF helps the bacteria to improve its adaptation to the medium. Moreover, it is now well known that co-inoculation reduces the total fermentation time (Jussier et al., 2006;Rosi et al., 2006;Massera et al., 2009;Pan et al., 2011;Abrahamse and Bartowsky, 2012;Knoll et al., 2012) and may limits the risk of spoilage by other microorganisms, such as the Brettanomyces species (Jussier et al., 2006;Curtin et al., 2007;Gerbaux et al., 2009). ...
... Chitosan addition, with or without batonnage, clearly helped to prevent Brettanomyces growth up to 6 months. On 2011 Sangiovese wines (Figures 2c & 2d), where Brettanomyces populations were slightly higher, it is interesting to notice the positive impact of bacteria co-inoculation on Brettanomyces contamination, as previously described [3]. Furthermore, Brettanomyces development occurred earlier in untreated wines, confirming chitosan impact. ...
Conference Paper
Full-text available
Brettanomyces bruxellensis and the consequences of its development in wines are a continuous threat for wine quality. This undesirable yeast is able to develop during aging under difficult conditions. It is also responsible for the production of negative aromatic compounds such as volatile phenols related to sensory descriptors such as animal-like, horse, barnyard, band aid and medicinal. Nowadays at an international scale, volumes concerned by this defect become significant. Several strategies are useful in order to control Brettanomyces and its development in musts and wines. However these strategies are not always sufficient. In this context, chitosan of fungal origin has been introduced as a new potential interesting tool to control Brettanomyces in the context of winemaking [1]. Recent studies have showed the impact of a fungal origin chitosan application on wines contaminated with Brettanomyces, leading to the elimination of Brettanomyces cells, even at high levels of populations up to 105 – 106 CFU/mL and at the dosage of 4 g/hL [2]. In these studies, the chitosan preparation was added and the wine racked off after 10 days and the efficiency of the treatment was evaluated in a short delay after the treatment. Due to the necessity to control wine microbiological stability during the period of aging, especially in the context of red wine aging in barrels, our research focuses on the application of an enological chitosan preparation in order to prevent wine from Brettanomyces contamination along the aging period at both pilot winery- and at winery-scale. This communication presents the evaluation of the impact of different addition protocols of an enological chitosan preparation on Brettanomyces population evolution and volatile phenols content along the aging, up to 9 months. To conclude, the results confirm the interest of chitosan as a preventive tool to control Brettanomyces in the context of wine aging.
... Co-inoculation Approach Findings show the production of biogenic amines being curtailed with co-inoculation strategies versus sequential inoculation strategies. It is also stated that co-inoculation often results in the inhibition of the production of 4-ethylphenol and 4-ethylguaiacol, both of which can cause a myriad of sensory and organoleptic problems (Gerbaux et al. 2009). Early inoculation with a high amount of selected O. oeni strains will not only allow a dominance over the indigenous bacteria flora, but due to the fact that bacteria cells are added very early in the winemaking process, the MLF will complete promptly after AF, which will then allow the product to be microbiologically stabilized at an earlier date. ...
Chapter
Although wine yeasts have been known for a long time, the production and use of active dry yeasts (ADY) began in the United States only in the mid-1960s and expanded worldwide thereafter. The history of controlled malolactic fermentation (MLF) is even shorter. Malolactic (ML) starter cultures for easy direct inoculation were only made available in the early 1990s. Important changes in the industry over the past two decades not only because of the global warming, which impacts on the grape composition, but also because of the challenges coming from new regulation, has forced the development of a range of new oenological products to help the wine industry to produce save and good quality wines, wines with less SO2 or lower alcohol, good acidity balance, and desired aromatic profile.
... Recent studies with IFV in Burgundy (Gerbaux) show co-inoculation with selected O. oeni strains can inhibit the growth of Brettanomyces (below 10 cell/mL) as opposed to the spontaneous control that is still contaminated with 500 cell/mL of Brettanomyces while the MLF is not completed and the wine is not stabilized [65]. ...
Article
Full-text available
Malolactic fermentation (MLF) in wine is an important step in the vinification of most red and some white wines, as stands for the biological conversion of l-malic acid into l-lactic acid and carbon dioxide, resulting in a decrease in wine acidity. MLF not only results in a biological deacidification, it can exert a significant impact on the organoleptic qualities of wine. This paper reviews the biodiversity of lactic acid bacteria (LAB) in wine, their origin, and the limiting conditions encountered in wine, which allow only the most adapted species and strains to survive and induce malolactic fermentation. Of all the species of wine LAB, Oenococcus oeni is probably the best adapted to overcome the harsh environmental wine conditions and therefore represents the majority of commercial MLF starter cultures. Wine pH is most challenging, but, as a result of global warming, Lactobacillus sp. is more often reported to predominate and be responsible for spontaneous malolactic fermentation. Some Lactobacillus plantarum strains can tolerate the high alcohol and SO2 levels normally encountered in wine. This paper shows the potential within this species for the application as a starter culture for induction of MLF in juice or wine. Due to its complex metabolism, a range of compositional changes can be induced, which may positively affect the quality of the final product. An example of a recent isolate has shown most interesting results, not only for its capacity to induce MLF after direct inoculation, but also for its positive contribution to the wine quality. Degrading hexose sugars by the homo-fermentative pathway, which poses no risk of acetic acid production from the sugars, is an interesting alternative to control MLF in high pH wines. Within this species, we can expect more strains with interesting enological properties.
... Previous studies suggest that a delay in malolactic fermentation can lead to elevated levels of volatile phenols [27]; the reason for that phenomenon is currently unknown. The malic acid degradation in Chardonnay and Pinot blanc shown in Figure 1 confirms that lysozyme can delay but not inhibit MLF if it is added in concentrations below the legal limit. ...
Article
Full-text available
Most yeast and bacteria in wine are able to metabolize hydroxycinnamic acids into volatile phenols via enzyme-mediated decarboxylation. Our trials performed in wine and model systems suggest that lysozyme addition prior to fermentation affects both bacterial activity and the release of hydroxycinnamic acids from their tartrate esters. This increases the potential for volatile phenol formation, as microorganisms can only metabolize free hydroxycinnamates. Wines with delayed malolactic fermentation due to lysozyme addition contained significantly higher concentrations of free hydroxycinnamic acids and elevated levels of volatile phenols in some cases. The reason for this is likely related to the side activity of lysozyme in combination with a detoxification mechanism that only occurs under stressful conditions for the yeast. Experiments in model systems indicate that lysozyme can affect the yeast at a pH higher than usually found in wine by attacking chitin in the bud scars of the cell walls and therefore weakening the cell structure. Free hydroxycinnamates can also affect yeast viability, making an increased release during fermentation problematic for a successful fermentation.
... Non-Saccharomyces yeast species were counted on Lysine agar medium (66 g/L Lysine medium (Oxoid®), 10 mL at 50% potassium lactate (v/v), 0.11 mL at 90% (v/v) lactic acid, 0.2 g/L chloramphenicol). Brettanomyces bruxellensis populations were determined by plating on a specific medium composed of 10 g/L yeast extract, 20 g/ L bacto-peptone, 20 g/L glucose, 0.1 g/L p-coumaric acid, 0.1 g/L ferulic acid, 0.03 g/L bromocresol green, 0.2 g/L chloramphenicol, 0.006% (w/v) cycloheximide (antifungal property), 20 g/L agar and pH was adjusted to 4.8 (Gerbaux, Briffox, Dumont, & Krieger, 2009). Lactic acid bacteria were enumerated on LAC agar medium composed of 78 mL/ L standardized grape juice, 33 g/L yeast extract, 0.6 mL/L Tween 80, 0.08 g/L MnSO 4 ·H 2 0, 20 g/L agar, 10 mL/L Delvocid® at 1% (w/v)) and acetic bacteria were determined by plating on a Mannitol agar medium composed of 25 g/L mannitol, 10 g/L yeast extract, 20 g/L agar, 10 mL/L Delvocid® at 1% (w/v) and 10 mL/L penicillin at 0.5% (w/v)). ...
... Non-Saccharomyces yeast species were counted on Lysine agar medium (66 g/L Lysine medium (Oxoid®), 10 mL at 50% potassium lactate (v/v), 0.11 mL at 90% (v/v) lactic acid, 0.2 g/L chloramphenicol). Brettanomyces bruxellensis populations were determined by plating on a specific medium composed of 10 g/L yeast extract, 20 g/L bacto-peptone, 20 g/L glucose, 0.1 g/L p-coumaric acid, 0.1 g/L ferulic acid, 0.03 g/L bromocresol green, 0.2 g/L chloramphenicol, 0.006% (w/v) cycloheximide (antifungal property), 20 g/L agar and pH was adjusted to 4.8 (Gerbaux, Briffox, Dumont, & Krieger, 2009). Lactic acid bacteria were enumerated on LAC agar medium composed of 78 mL/L standardized grape juice, 33 g/L yeast extract, 0.6 mL/L Tween 80, 0.08 g/L MnSO 4 ·H 2 0, 20 g/L agar, 10 mL/L Del-vocid® at 1% (w/v)) and acetic bacteria were determined by plating on a Mannitol agar medium composed of 25 g/L mannitol, 10 g/L yeast extract, 20 g/L agar, 10 mL/L Delvocid® at 1% (w/v) and 10 mL/L penicillin at 0.5% (w/v)). ...
... It is well known that the period from the end of the AF to the beginning of the FML is specifically conducive to the development of Brettanomyces/Dekkera. Early wine inoculation with LAB, immediately after AF or co-inoculation, has been proved a simple and effective method to prevent Brettanomyces development and the production of off-flavors due to high concentrations of ethylphenols [45]. This study showed that phenol content in wine elaborated by co-inoculation of LAB starters was significantly lower than those ones by spontaneous MLF. ...
Article
Full-text available
: This study investigates the effects of simultaneous inoculation of a selected Saccharomyces cerevisiae yeast strain with two different commercial strains of wine bacteria Oenococcus oeni at the beginning of the alcoholic fermentation on the kinetics of malolactic fermentation (MLF), wine chemical composition, and organoleptic characteristics in comparison with spontaneous MLF in Tempranillo grape must from Castilla-La Mancha (Spain). Evolution of MLF was assessed by the periodic analysis of L-malic acid through the enzymatic method, and most common physiochemical parameters and sensory traits were evaluated using a standardized sensory analysis. The samples were analyzed by GC/MS in SCAN mode using a Trace GC gas chromatograph and a DSQII quadrupole mass analyzer. Co-inoculation reduced the overall fermentation time by up to 2 weeks leading to a lower increase in volatile acidity. The fermentation-derived wine volatiles profile was distinct between the co-inoculated wines and spontaneous MLF and was influenced by the selected wine bacteria used in co-inoculation. Co-inoculation allows MLF to develop under reductive conditions and results in wines with very few lactic and buttery flavors, which is related to the impact of specific compounds like 2,3-butanedione. This compound has been also confirmed as being dependent on the wine bacteria used.
... This strategy may reduce the off-flavours production by Brettanomyces spp. strains in wine (Gerbaux, Briffox, Dumont, & Krieger, 2009). In addition, the production of the volatile phenols seems to be more related to the strain diversity of B. bruxellensis and the time, than the cynnamoyl esterase activity of the malolactic starters such as Oenococcus oeni (Madsen et al., 2017). ...
Article
Background The application of emerging technologies for the food preservation is a relevant topic for the industry; these technologies are highly efficient to reduce the growth of spoilage microorganisms as well as the production of undesirable microbial metabolites in foods and the processing environment. Spoilage caused by the yeast metabolic activity affects the wine marketability. These novel technologies can be easily implemented during dynamic and customized winemaking processes, in order to control the microbial contaminations and to preserve the wine quality. Scope and approach During the last two decades, the Brettanomyces spp. contamination in the bottled wines and the winery environment has attracted interest due to production of the volatile phenol compounds, the high stress resistance and the peculiar metabolic features. The use of the emerging technologies, such as high hydrostatic pressure, ultrasounds, pulsed electric fields, UV irradiation, microwaves, ozone and electrolyzed water, novel finishing agents, and biotechnological approaches resulted useful to reduce the contamination levels and the production of off-flavours. In addition, the application of the emerging technologies allowed the reduction of sulphur dioxide, considering its allergenic properties and the raise of Brettanomyces spp. resistance to this compound. The effect of these technologies on nutritional and sensory properties of wines is also discussed. Key findings and conclusions This review highlights some useful novel approaches to control Brettanomyces spp. during winemaking, allowing the producers to follow the “hurdle concept” and to minimize wine sensory changes. Full-text at: https://authors.elsevier.com/a/1aiOO3I9F4DAkQ
... Biogenic amines re- present additional undesirable bio-products resulting from more commonly associated with wine ageing and cellar equipment. Due to its tolerance of ethanol and lack of nutrients, Brettanomyces often spoils wine during ageing in oak barrels, or when alcoholic or mal- olactic fermentation is stuck (Gerbaux, Briffox, Dumont, & Krieger, 2009;Wedral et al., 2010). Furthermore, Brettanomyces populations can also be found in bottled wines, due to contamination in the early stage of winemaking, insufficient SO 2 concentrations and inefficient filtration before bottling (Curtin, Kennedy, & Henschke, & P. A., 2012;Oelofse et al., 2008). ...
... The incubation temperature was 28 • C for 48 h for both agar media. B. bruxellensis populations were determined by plating on a specific medium composed of 10 g/L yeast extract, 20 g/L bacto-peptone, 20 g/L glucose, 0.1 g/L p-coumaric acid, 0.1 g/L ferulic acid, 0.03 g/L bromocresol green, 0.2 g/L chloramphenicol, 0.006% (w/v) cycloheximide (antifungal property), 20 g/L agar, and pH was adjusted to 4.8 as described by Gerbaux et al. (2009). The incubation temperature was 28 • C for 7 days for this specific agar medium. ...
Article
Full-text available
In wine, one method of limiting the addition of sulphites, a harmful and allergenic agent, is bio-protection. This practice consists of the early addition of microorganisms on grape must before fermentation. Non-Saccharomyces yeasts have been proposed as an interesting alternative to sulphite addition. However, scientific data proving the effectiveness of bio-protection remains sparse. This study provides the first analysis of the chemical and microbiological effects of a Metschnikowia pulcherrima strain inoculated at the beginning of the red winemaking process in three wineries as an alternative to sulphiting. Like sulphiting, bio-protection effectively limited the growth of spoilage microbiota and had no influence on the phenolic compounds protecting musts and wine from oxidation. The bio-protection had no effect on the volatile compounds and the sensory differences were dependent on the experimental sites. However, a non-targeted metabolomic analysis by FTICR-MS highlighted a bio-protection signature.
Article
Previously six selected Oenococcus oeni strains (P2A, P3A, P3G, P5A, P5C and P7B) have been submitted to further characterization in order to clarify their potential as malolactic starters. Laboratory scale vinifications gave an insight of the most vigorous strains: both P2A and P3A strains were able to conclude malolactic fermentation (MLF) in less than 15 days. The remaining strains showed good viability and were able to successfully finish MLF in the established analysis time, except for the strain P5A, which viability was totally lost after inoculation. Also spontaneous fermentation was not initiated. None of the strains was biogenic amine producer; however, P5C strain significantly increased the concentration of volatile phenol-precursor hydroxycinnamic acids after MLF. Regarding the evolution of wine aromatic compounds, main changes were detected for both ethyl and acetate esters after MLF; however, key aromatic compounds including alcohols, terpenes or acids were also found to significantly increase. Principal component analysis classified the strains in two distinct groups, each one correlated with different key volatile compounds. P2A, P3A, P3G and P5C strains were mainly linked to esters, while P7B and the commercial strain Viniflora OENOS showed higher score for diverse compounds as hexanoic acid, β-damascenone, linalool or 2-phenylethanol. These results confirmed the specific impact of each strain on wine aroma profile, which could lead to the production of wines with individual characteristics, in which the reliability and safety of MLF is also ensured.
Chapter
The grapevine Syrah is originated from France, and is used in several winegrowing regions around the world. It is a grape variety used successfully worldwide, producing wines with high variability of styles, with complexity and providing numerous aromas and flavors, in young and/or aged/guard wines. The most valued assets of Syrah is the capacity to adapt to different climates and soils due to its plasticity, being commercially used over many years ago in several countries. In this chapter we show the main characteristics of Syrah variety worldwide, with researches carried out in different winegrowing zones in Brazil, in traditional sites and also in new viticultural regions. The results show the variation of physicochemical composition of the grapes and wines, as well as the sensory profiles of wines mainly influenced by different climates, rootstocks and winemaking protocols.
Article
Malolactic fermentation (MLF) is an integral step in red winemaking, which in addition to deacidifying wine can also influence the composition of volatile fermentation-derived compounds with concomitant affects on wine sensory properties. Long-established winemaking protocols for MLF induction generally involve inoculation of bacteria starter cultures post alcoholic fermentation, however, more recently there has been a trend to introduce bacteria earlier in the fermentation process. For the first time, this study shows the impact of bacterial inoculation on wine quality parameters that define red wine, including wine colour and phenolics, and volatile fermentation-derived compounds. This study investigates the effects of inoculating Shiraz grape must with malolactic bacteria at various stages of alcoholic fermentation [beginning of alcoholic fermentation (co-inoculation, with yeast), mid-alcoholic fermentation, at pressing and post alcoholic fermentation] on the kinetics of MLF and wine chemical composition. Co-inoculation greatly reduced the overall fermentation time by up to 6 weeks, the rate of alcoholic fermentation was not affected by the presence of bacteria and the fermentation-derived wine volatiles profile was distinct from wines produced where bacteria were inoculated late or post alcoholic fermentation. An overall slight decrease in wine colour density observed following MLF was not influenced by the MLF inoculation regime. However, there were differences in anthocyanin and pigmented polymer composition, with co-inoculation exhibiting the most distinct profile. Differences in yeast and bacteria metabolism at various stages in fermentation are proposed as the drivers for differences in volatile chemical composition. This study demonstrates, with an in-depth analysis, that co-inoculation of yeast and bacteria in wine fermentation results in shorter total vinification time and produces sound wines, thus providing the opportunity to stabilise wines more rapidly than traditional inoculation regimes permit and thereby reducing potential for microbial spoilage.
Chapter
Wine is an ancient, traditional, and widely popular alcoholic beverage fermented from grapes. Winemaking requires a succession of biotransformations that must be well managed by the winemaker. This involves not only the natural microflora but also, often, selected starters, added to the must or wine at the appropriate time. Microbial resource management has played a central role in the wine industry. There are two different fermentations in the winemaking process. The alcoholic fermentation process is mediated by the metabolic activity of common yeast, Saccharomyces cerevisiae, and the malolactic fermentation (MLF), by that of lactic acid bacteria belonging to the ancient genera-Lactobacillus, Oenococcus, Leuconostoc, and Pediococcus with a predominance of the species Oenococcus oeni. MLF is the process by which certain LAB convert l-malic acid into l-lactic acid and carbon dioxide. This fermentation is essential to produce some red wines, white wines, and sparkling base wines. The softening of the wine, by increasing its pH, is the main function of MLF, and the removal of a microbial carbon source impacts the flavor profile of the finished wines. Several species of lactic acid bacteria (LAB) can undertake MLF, of which O. oeni is one of the species most adapted to the harsh conditions of wine. MLF bacteria have the ability to transport malate into their cytoplasm via a specific malate permease, in addition to passive transport, and produce a cytoplasmic malolactic enzyme responsible for the malic acid decarboxylation. For the success of MLF, the selection of the right bacteria depends on the control of appropriate physico-chemical parameters.
Article
Malolactic fermentation (MLF) of Tempranillo Rioja wines (Spain) inoculated with two lactic acid bacteria (LAB) strains were studied and compared with spontaneous MLF. Inoculation with selected Oenococcus oeni lyophila shortened MLF duration up to 19 days and lead to wines with more fresh and fruity characters, especially when implantation was 100%. We demonstrated modifications in the concentration of volatile and nitrogenous compounds and a good correlation between analytical and sensory attributes was also noted. In addition, the low initial amino acid concentration and the consumption of these compounds by the inoculated yeast strain during alcoholic fermentation resulted in wines with very low biogenic amines levels (under 3.75 mg L−1) after MLF and 3 month storage period in all cases. The results showed the significance of choose the most suitable starter to elaborate quality wines and suggest the control of amino acid content in must and wine to prevent the formation of biogenic amines.
Article
Full-text available
Brettanomyces bruxellensis and the conse-quences of its development in wines are a contin-uous threat for wine quality. In this context, chi-tosan of fungal origin was introduced as a new tool to control B. bruxellensis in the context of winemaking. Recent studies have showed the impact of a fungal origin chitosan application on wines contaminated with B. bruxellensis, leading to the elimination of B. bruxellensis cells. In these studies, the chitosan preparation was added, the wine racked off after 10 days and the efficiency of the treatment was evaluated in a short delay after the treatment. This study focused on the evalua-tion of the impact of different addition protocols of an enological chitosan preparation on B. brux-ellensis population evolution and volatile phenols content along the aging, up to 9 months. The results confirm the interest of fungal origin chi-tosan as a preventive tool to control B. bruxellen-sis in the context of wine aging.
Article
Malolactic fermentation (MLF) is the bacterially driven decarboxylation of L-malic acid to L-lactic acid and carbon dioxide, and brings about deacidification, flavour modification and microbial stability of wine. The main objective of MLF is to decrease wine sourness by a small increase in wine pH via the metabolism of L-malic acid. Oenococcus oeni is the main lactic acid bacterium to conduct MLF in virtually all red wine and an increasing number of white and sparkling wine bases. Over the last decade, it is becoming increasingly recognized that O. oeni exhibits a diverse array of secondary metabolic activities during MLF which can modify the sensory properties of wine. These secondary activities include the metabolism of organic acids, carbohydrates, polysaccharides and amino acids, and numerous enzymes such as glycosidases, esterases and proteases, which generate volatile compounds well above their odour detection threshold. Phenotypic variation between O. oeni strains is central for producing different wine styles. Recent studies using array-based comparative genome hybridization and genome sequencing of three O. oeni strains have revealed the large genomic diversity within this species. This review will explore the links between O. oeni metabolism, genomic diversity and wine sensory attributes.
Étude des phénols volatils dans les vins de Pinot noir en Bourgogne
  • V Gerbaux
  • S Jeudy
  • C Monamy
Gerbaux, V., S. Jeudy, and C. Monamy. 2000. Étude des phénols volatils dans les vins de Pinot noir en Bourgogne. Bull. OIV. 835-836:581-599.
Optimisation de la macération finale à chaud, intérêt d'un enzymage et d'une macération sous chapeau immergé pour la vinification du Pinot noir
  • V Gerbaux
  • C Briffox
  • B Vincent
Gerbaux, V., C. Briffox, and B. Vincent. 2003. Optimisation de la macération finale à chaud, intérêt d'un enzymage et d'une macération sous chapeau immergé pour la vinification du Pinot noir. Rev. Fr Oenol. 201:16-21.