Wine corks decontamination using plasma activated water.

Cork taint provides off-odors and changes negatively wine composition. In fact, it is one of the most important causes of discarding bottled wine. 2,4,6-Trichloroanisole (TCA) is the most known molecule responsible of that problem. In this study, cork stoppers were artificially contaminated with a multi-pattern solution which contained different chloroanisoles and chlorophenols. Contaminated corks were immersed for 3 h in four Plasma Activated Water (PAW) generated during 1.5 min, 5 min, 15 min and 30 min. The products of OH•, NO• and NO2• with phenol were determined by HPLC for each PAW. After treating contaminated corks with PAW generated during 5 min, more than 72 % of TCA was removed and it was suggested OH• as the main reactive species decomposing TCA. Finally, other chloroanisole and chlorophenol molecules were examined after PAW treatments showing successful reductions in almost every molecule. Thus, it was presented PAW treatment as an easy solution for solving cork taint problems in wine industry.

Influence of the temperature and the origin of CO2 (anaerobiosis methodology) on the intracellular fermentation of wines made by carbonic maceration.

BACKGROUND: The present study aimed to determine the optimal conditions for making wines by the carbonic maceration (CM) method. In this test, we attempted to identify the causes of the higher volatile acidity of some wines vinified by this method. Accordingly, we measured the development and speed of intracellular fermentation inside the whole grapes under different vinification conditions. RESULTS: An active fermentation of the must in the tanks produced by inoculation with active dry yeasts was more efficient for the process than the addition of exogenous carbon dioxide (CO2 ). In addition, in CM vinification, the moment of devatting had a great influence on the content of acetaldehyde and acetic acid in the whole grapes. CONCLUSION: Yeast inoculation in the tanks and control of the devatting time are technological tools that could play an important role in the characteristics of the wines produced by carbonic maceration, especially with respect to acetic acid content. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Influence of the carbonic maceration winemaking method on the physicochemical, colour, aromatic and microbiological features of tempranillo red wines.

The aim of the study was to determine the differences in the microbiological, physical-chemical, aromatic and phenolic composition between two winemaking methods: carbonic maceration and the standard method of destemming and crushing. We analysed 84 commercial Rioja wines made from the Tempranillo grape variety during the 2017 vintage, 40 had been made by carbonic maceration and 44 by destemming and crushing. Despite the heterogeneity within the two groups of wines, it was possible to differentiate between them. Wines made by carbonic maceration presented higher aromatic quality due to their higher total content of esters and acetates, as well as a greater colour intensity due to a higher phenolic content and higher rates of ionization and polymerization. In addition, it was observed that the antioxidant activity, the content in coumaroyl derivatives of anthocyanins and the vitisins A and B were considerably greater in wines made by carbonic maceration.

Effect of the Sequential Inoculation of Non-Saccharomyces/Saccharomyces on the Anthocyans and Stilbenes Composition of Tempranillo Wines.

The phenolic compounds of red wines are responsible for their color, astringency, and antioxidant properties. The fermentative yeasts might be used to modulate wines in terms of their color, aroma and probably healthy properties. In this study, six non-Saccharomyces species were tested because they might enhance the properties of red Tempranillo wines from Rioja. The results confirmed that the anthocyanins and stilbenes composition of wine can be modulated with the use of a specific fermentation starter. Metschnikowia pulcherrima, Zygosaccharomyces bailii, Candida zeylanoides, and Torulaspora delbrueckii achieved the greatest improvements of the monomeric anthocyanin composition, and the latter three yeast species achieved the best results of stilbene composition when compared to S. cerevisiae and the other non-Saccharomyces yeasts. Overall, results suggested that the use of M. pulcherrima, Z. bailii, C. zeylanoides and T. delbrueckii as fermentation starters could be of great interest to achieve wines with better color and likely healthy properties.

Wine aroma evolution throughout alcoholic fermentation sequentially inoculated with non- Saccharomyces/Saccharomyces yeasts.

Nine non-Saccharomyces yeasts belonging to 6 species (Torulaspora delbrueckii, Metschnikowia pulcherrima, Lachancea thermotolerans, Zygosaccharomyces bailii, Williopsis pratensis and Candida zeylanoides) and two mixed inoculum of T. delbrueckii and L. thermotolerans were screened for aroma formation and fermentative behaviour in sequential inoculations with Saccharomyces cerevisiae. The main differences in aromatic composition within wines were detected in the first stages of vinification between S. cerevisiae and non-Saccharomyces species, but not within the latter species. Most of the wines made with non-Saccharomyces in sequential fermentation with S. cerevisiae tended to produce higher ethanal and glycerol and lower volatile acidity than those inoculated only with S. cerevisiae. However, no significant differences were found in alcohol content. The addition of S. cerevisiae tended to standardise the wines and only those made with T. delbrueckii and L. thermotolerans, both alone and together, showed different aromatic profiles. Wines elaborated with non-Saccharomyces yeasts that quickly decreased in tanks showed characteristics similar than those made only with S. cerevisiae. Therefore, sequential inoculation of non-Saccharomyces/Saccharomyces is a useful tool to modulate wine characteristics, but only with species which remain longer in tanks. These findings can be useful to carry out selection processes within these species.

Impact of Chemical and Biological Fungicides Applied to Grapevine on Grape Biofilm, Must, and Wine Microbial Diversity.

This study was aimed to measure the impact of the application of a bio-fungicide against Botrytis cinerea on the microbiota involved in the alcoholic fermentation (AF) of Tempranillo Rioja wines. For this purpose, a bio-fungicide composed of the biological control bacterium Bacillus subtilis QST713 was applied to the vineyard. The microbial diversity was analyzed from grape biofilm to wine. Impact on microbial diversity was measured employing indexes assessed with the software PAST 3.10 P.D. Results were compared to non-treated samples and to samples treated with a chemical fungicide mainly composed by fenhexamid. Overall, the impact of the biological-fungicide (bio-fungicide) on the microbial diversity assessed for grape biofilm and for musts was not remarkable. Neither of the tested fungicides enhanced the growth of any species or acted against the development of any microbial groups. The bio-fungicide had no significant impact on the wine microbiota whereas the chemical fungicide caused a reduction of microbial community richness and diversity. Although environmental threats might generate a detriment of the microbial species richness, in this study the tested bio-fungicide did not modify the structure of the microbial community. Indeed, some of the Bacillus applied at the grape surface, were detected at the end of the AF showing its resilience to the harsh environment of the winemaking; in contrast, its impact on wine quality during aging is yet unknown.

Evaluating a preventive biological control agent applied on grapevines against Botrytis cinerea and its influence on winemaking.

BACKGROUND: This research was aimed to study the influence on grape and wine quality and on the fermentation processes of the application of a preventive biological treatment against Botrytis cinerea in Tempranillo Rioja grapevines. For this purpose, a biofungicide containing Bacillus subtilis QST713 was applied twice to the vineyard. RESULTS: Results were compared with non-treated samples from the same vineyard and with samples treated with a chemical fungicide composed of fenhexamid. Data showed that general grape quality and spontaneous alcoholic fermentation performance were not influenced by either fungicide application. The chemical fungicide had a considerable influence on the clonal diversity of Saccharomyces cerevisiae species, which led to the alcoholic fermentation. Furthermore, it caused longer malolactic fermentation than with the biological fungicide and in the control. The biofungicide made malolactic fermentation 1 day shorter because the establishment of the commercial lactic acid bacteria used as a starter culture was total. After malolactic fermentation, the wines did not show significant differences in general oenological parameters. CONCLUSION: Preventive biofungicide treatment against B. cinerea did not negatively influence the quality of grapes and wines and the fermentation processes. Therefore, biological control of B. cinerea with B. subtilis applied on grapevines could be advisable in oenological terms. © 2018 Society of Chemical Industry.