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Barrel aging is crucial for the production of high-quality wines, with barrel reuse playing a key role in this process. Therefore, disinfecting and cleaning barrels are vital to prevent health and safety issues, being B. bruxellensis one of the most extended problems. In this study, naturally contaminated oak barrels with B. bruxellensis were immersed during 3 h in four Plasma Activated Water (PAW) generated for 1.5 min, 5 min, 15 min and 30 min. The presence of secondary radicals (OH•, NO•, NO2•) was observed after HPLC and spectrometry analysis. The results suggested that those reactive species played an important role in the inactivation of B. bruxellensis. PAW_5 (generated during 5 min), which achieved a reduction of 3.49 ± 0.83 logarithmic units in B. bruxellensis population, was chosen as the best one in terms of economic and time consumption. Thus, an ecofriendly, sustainable and inexpensive solution was presented to inactivate B. bruxellensis from wine barrels.

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.

In winemaking, excessive production of acetic acid by acetic acid bacteria poses a major challenge, leading to rejection of wine by consumers. The aim of this study was to devise an economically viable and easy-to-use liquid culture medium for the preventive detection of microorganisms capable of generating acetic acid in wine. The modified medium incorporated specific nutrients that favored the growth of acetic acid bacteria and increased selectivity. Under varying conditions and with different types of wine, this medium was tested together with inoculated samples, comparing the occurrence of acetic acid and olfaction. The result was a new liquid medium based on olfactometry, designed to facilitate its use in wineries, even by untrained personnel and without the need for complex laboratory equipment. Validation was carried out on a variety of wines, determining the onset of the presence of acetic acid in the medium. This innovative culture medium provides a means to estimate the concentration of micro-organisms capable of producing acetic acid in wine. Its application in wineries facilitates proactive decision making, avoiding undesirable increases in acetic acid concentration.

The demand for chemical-free beverages is posing a challenge to the wine industry to provide safe and healthy products with low concentrations of chemical preservatives. The development of new technologies, such as Atmospheric Pressure Cold Plasma (APCP), offers the wine industry the opportunity to contribute to this continuous improvement. The purpose of this research is to evaluate the effect of Argon APCP treatment, applied in both batch and flow systems, on Tempranillo red wine quality. Batch treatments of 100 mL were applied with two powers (60 and 90 W) at four periods (1, 3, 5, and 10 min). For flowing devices, 750 mL of wine with a flow of 1.2 and 2.4 L/min were treated at 60 and 90 W for 25 min and was sampled every 5 min. Treatments in batch resulted in wines with greater color intensity, lower tonality, and higher content in total phenolic compounds and anthocyanins, so that they were favorable for wine quality. Among the batch treatments, the one with the lowest power was the most favorable. Flow continuous treatments, despite being more appropriate to implement in wineries, neither led to significant improvements in the chromatic and phenolic wine properties nor caused wine spoilage.

The aim of the study was to determine the relevance of microorganisms present during the carbonic maceration vinification in the specific attributes of young red wines produced by this method. For this purpose, wines were made by the two winemaking methods: carbonic maceration and the standard method of destemming and crushing, starting from the same batch of grapes. The microbiological population of the initial grapes was homogenised by means of a “pied de cuve”, and afterwards, the microbial evolution (yeasts, lactic acid and acetic acid bacteria) was followed in different fermentation stages. Finally, the wines obtained were analysed and tasted. After homogenising the initial microbiota, small microbiological differences were detected both in the counts of microorganisms and in the species involved. Nevertheless, the wines obtained were remarkably different, both in their chemical composition and in their organoleptic characteristics. This would indicate that, although the microbiota present could influence some of the characteristics of carbonic maceration wines, the main factor that determines the unique characteristics of these wines is their particular production procedure based in the intracellular fermentation.

The demand for chemical-free beverages is posing a challenge to the wine industry to provide safe and healthy products with low concentrations of chemical preservatives. The development of new technologies, such as Atmospheric Pressure Cold Plasma (APCP), offers the wine industry the opportunity to contribute to this continuous improvement. The purpose of this research is to evaluate the effect of Argon APCP treatment, applied in both batch and flow systems, on Tempranillo red wine quality. Batch treatments of 100 mL were applied with two powers (60 and 90 W) at four periods (1, 3, 5, and 10 min). For flowing devices, 750 mL of wine with a flow of 1.2 and 2.4 L/min were treated at 60 and 90 W for 25 min and was sampled every 5 min. Treatments in batch resulted in wines with greater color intensity, lower tonality, and higher content in total phenolic compounds and anthocyanins, so that they were favorable for wine quality. Among the batch treatments, the one with the lowest power was the most favorable. Flow continuous treatments, despite being more appropriate to implement in wi

Spontaneous fermentation is the most traditional way and a low-intervention method for conducting alcoholic fermentation in wineries, giving rise to the most complex wine profiles. However, inoculation with single culture inocula of Saccharomyces cerevisiae strains has become widespread in the modern wine industry. Nevertheless, some authors have pointed out that the use of the same yeasts in all the winegrowing regions of the world can cause a loss of typicity and have a standardizing effect on the wines. For this reason, many wineries and regions are carrying out programs of isolation and selection of yeasts that are typical of their vineyards/wineries. The aim of this work was to study the ecology of spontaneous fermentations in 11 wineries from all over the Rioja qualified designation of origin (Spain) during 3–4 consecutive years in order to establish the existence of typical strains belonging to wineries, sub-zones, or regional ecosystems. The results obtained showed a great diversity of strains of Saccharomyces cerevisiae in each fermentation studied. These strains were different each year in each winery, and hardly any common strains were detected between neighboring wineries, which would indicate that there are no representative strains from the winery or the area.

This study was aimed to analyze the effects of the nitrogen foliar application, and elicitation on microbial populations of musts. The nitrogenous compounds were raw and treated wastewater from mushroom industry and a commercial yeast derivate; the elicitors were methyl jasmonate, chitosan and one commercial elicitor from a yeast source. Those six products were sprayed as pre-harvest treatment over the leaves of Tempranillo grapevines for improving quality and maturity of grapes. The applications of raw and treated wastewaters from mushroom industry, chitosan and methyl jasmonate elicitation did not cause changes in microbial diversity of must samples. In contrast, spraying commercial yeast derivate products made the must microbiota reach a high richness of species that would be positive in ecological terms. This research succeeded in establishing the impacts of foliar applications in the grapevines on the microbial community, and in any case, negative impacts were observed so that, presumably, these foliar applications can be perfectly implemented as agronomic practice.

The effects of pulsed electric field (PEF) technology on the microbiota of wines aging in oak barrels without additional chemical preservatives were studied. Two differently aged wines without sensory deviations, naturally having Brettanomyces/Dekkera, were PEF-treated. Results showed that the PEF treatment in continuous flow inactivated the most abundant spoilage microbial population of each wine. However, the recovery of some microorganisms after treatment was also observed. Therefore, to determine PEF as an alternative to the use of SO, additional studied are needed with a wider sampling set.

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.

Oak wood barrel sanitization is crucial in terms of food safety, since barrels enrich the wine in aromas and taste sensation and provide physico-chemical stability. The most used method is barrel sulphuring; however, there is a European prohibition (Directive 98/8/CE2) that does not allow the use of this method. For this reason, the aim of the present work was to study an alternative technology, the atmospheric pressure cold plasma (APCP) to sanitize oak wood staves. Three wine spoilage microorganisms, two bacteria (Pediococcus pentosaceus and Acetobacter pasteurianus) and a yeast (Brettanomyces bruxellensis), were inoculated in the wood staves. Then, they were exposed to APCP device at a 12-passes treatment with different plasma powers (90 W and 500 W) and plasma gases (air, nitrogen and argon). A total inactivation of the yeast was achieved after the air and nitrogen plasma treatments, being the most sensitive microorganism to the APCP. In terms of bacteria, P. pentosaceus and A. pasteurianus showed a lower inactivation with respect to their controls. The reactive oxygen and nitrogen species generated during the plasma generation process seem to play the main role on the microbial inactivation. Finally, no morphological modifications on the wood surface were identified after APCP treatments.