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This study investigated the chemical aromatic profiles of 60 volatile organic compounds (VOCs), including 21 terpenes, 6 norisoprenoids, 6 volatile phenols, 4 C-6 alcohols, and 23 esters, in Graševina wines originating from Slavonia and Podunavlje sub-regions (Croatia). Headspace solid-phase microextraction gas chromatography coupled with mass spectrometric detection (HS-SPME-GCMS) was used to assess 60 VOCs, and a novel HS-SPME-GCMS method for the determination of terpenes and norisoprenoids was developed and validated. Statistical analysis found no significant differences between VOCs present in Graševina wines and others wines (Chardonnay and Pinot gris); nonetheless, comparison of VOC fingerprints between different wines from the same producer showed that four terpenes (α-terpinene, γ-terpinene, 1,4-cineol, and 4-terpineol) were present in higher amounts in Graševina wines when compared to other wines. By exclusively examining VOCs within Graševina wines through the utilization of a heatmap and hierarchical clustering, a distinct visualization of samples and VOCs emerged, highlighting the vintage effect. Simultaneously, a partial least squares discriminant analysis model was developed with a confidence interval of 95%, demonstrating a noticeable distinction between samples originating from the western and eastern regions. Furthermore, by employing the heatmap using only VOCs from the terpene and norisoprenoidic groups, a clear separation of samples into two groups was observed based on geographical origin; namely, higher concentrations of norisoprenoids and terpenes were observed in the Slavonia sub-region. These results suggest that terpenes and norisoprenoids to a lower extent may be valuable aromatic markers for the regional typicality of Graševina wines. [ABSTRACT FROM AUTHOR]

Saccharomyces cerevisiae is commonly used for the production of alcoholic beverages, including cider. In this study, we examined indigenous S. cerevisiae and S. uvarum strains, both species commonly found in cider from Hardanger (Norway), for their strain-specific abilities to produce volatile and non-volatile compounds. Small-scale fermentation of apple juice with 20 Saccharomyces strains was performed to evaluate their aroma-producing potential as a function of amino acids (AAs) and other physicochemical parameters under the same experimental conditions. After fermentation, sugars, organic acids, AAs, and biogenic amines (BAs) were quantified using the HPLC–UV/RI system. A new analytical method was developed for the simultaneous determination of nineteen AAs and four BAs in a single run using HPLC–UV with prior sample derivatization. Volatile compounds were determined using HS-SPME-GC-MS. Based on 54 parameters and after the removal of outliers, the nineteen strains were classified into four groups. In addition, we used PLS regression to establish a relationship between aroma compounds and predictor variables (AAs, BAs, organic acids, sugars, hydrogen sulfide (H2S) production, CO2 release) of all 19 strains tested. The results of the VIP show that the main predictor variables affecting the aroma compounds produced by the selected yeasts are 16, belonging mainly to AAs. [ABSTRACT FROM AUTHOR]

Preventing wine from developing off-flavours is important, but better understanding the wine component at the root of a typical and unique sensory profile is another topic of high interest for the wine industry. Wine is a mark of cultural heritage, is an ancient and celebrated beverage, and is a global industry that is today valued at approximately USD 450 billion. Nowadays, the wine sector is facing dramatic challenges such as climate change, sky-rocketing demand for unique and environmentally friendly wines with fewer intrants, and the extreme competitiveness of wine markets. [Extracted from the article]

Electrocatalysis using low-cost materials is a promising, economical strategy for remediation of water contaminated with organic chemicals and microorganisms. Here, we report the use of iron phosphide (Fe2P) precatalyst for electrocatalytic water oxidation; degradation of a representative aromatic hydrocarbon, the dye rhodamine B (RhB); and inactivation of Escherichia coli (E. coli) bacteria. It was found that during anodic oxidation, the Fe2P phase was converted to iron phosphate phase (Fe2P-iron phosphate). This is the first report that Fe2P precatalyst can efficiently catalyze electrooxidation of an organic molecule and inactivate microorganisms in aqueous media. Using a thin film of Fe2P precatalyst, we achieved 98% RhB degradation efficiency and 100% E. coli inactivation under an applied bias of 2.0 V vs. reversible hydrogen electrode in the presence of in situ generated reactive chlorine species. Recycling test revealed that Fe2P precatalyst exhibits excellent activity and reproducibility during degradation of RhB. High-performance liquid chromatography with UV-Vis detection further confirmed the electrocatalytic (EC) degradation of the dye. Finally, in tests using Lepidium sativum L., EC-treated RhB solutions showed significantly diminished phytotoxicity when compared to untreated RhB. These findings suggest that Fe2P-iron phosphate electrocatalyst could be an effective water remediation agent. [ABSTRACT FROM AUTHOR]

BACKGROUND: The use of indigenous selected starters in winemaking is gaining interest due to certain advantages for the sensory quality of the wine. The present work shows the results of a laboratory experiment in which the influence of selected indigenous yeasts on the colour characteristics of Pinot Noir was studied with the use of high hydroxycinnamate decarboxylase activity yeasts. Pichia guilliermondii ZIM624 and Wickerhamomyces anomalus S138 yeasts were used in sequential fermentation with two strains of Saccharomyces cerevisiae, the native ZIM2180 strain and commercial Fermol Premier Cru (FPC). RESULTS: In co‐inoculation fermentations, non‐Saccharomyces yeasts decreased colour intensity (on average by 25.5%). In wines fermented with ZIM624, the concentration of vinylphenolic pyranoanthocyanins increased (average concentration 1.5 mg L−1). However, vitisin concentration was significantly higher in S138 + FPC fermentation (1.3 mg L−1 and an average of 0.9 mg L−1, respectively). Pinot Noir wines fermented with only ZIM2180 and sequential inoculation of ZIM624 + ZIM2180 resulted in significantly higher colour intensity (6.1 ± 0.0 AU and 4.4 ± 0.0 AU, respectively) and lower wine hue parameters compared to other wines. Sensory evaluation also showed that both wines had the highest perceived colour intensity and purple colour suggesting improvement in wine quality parameters. CONCLUSIONS: The results confirmed that selected indigenous starters made out of Saccharomyces and non‐Saccharomyces yeasts can alter Pinot Noir wine colour parameters and improve wine colour properties. Those yeasts properties should be investigated prior to the development of new commercial starters but also be considered in large scale spontaneous fermentations of low colour intensity red wines like Pinot Noir. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The existing multisensory literature suggests that the combination of the different human senses in a controlled fashion during food/drink experiences can provide more enjoyment to consumers. The present research reviews recent literature relating multisensory perception with wine experiences, focusing on the interaction of the five basic senses (taste, smell, vision, touch, and sound). This is mostly being assessed from a perceptual and behavioral consumer perspective. Here, the authors report different ways in which such interactions across these senses can affect the way a wine is experienced, prior to, during, and even after tasting. The authors finish this literature review by providing some insights in the context of wine and food pairing, while also generally reflecting on potential future work. These insights may be inspirational for a diverse group of organizations working with wine. Based on such multisensory approaches, it may be possible to bring unforeseen sensations to the different wine experiences, while at the same time stressing particular sensory and/or emotional attributes. [ABSTRACT FROM AUTHOR]

Anthocyanins are being explored as natural food colorants thanks to their diverse color portfolio. However, the main challenge for food industry application is their instability and pH-associated color change which occurs in majority of the foods containing natural pigments. Anthocyanin-derived pigments pyranoanthocyanins are being largely investigated as stable natural food colorants, since they are resistant to pH, SO2 or ascorbic acid. In this study two experimental approaches were compared for the synthesis of pyranoanthocyanin vitisin A and three vinylphenolic pyranoanthocyanins (malvidin-3-O-glucoside-4-vinylcatechol, malvidin-3-O-glucoside-4-vinylphenol, and malvidin-3-O-glucoside-4-vinylguaiacol). Synthesis of pyranoanthocyanins with artificial ageing of model wine solution at 30 °C was compared to the fermentation of model grape must with yeasts. Both model solutions contained Vitis vinifera L. cv. Pinot Noir anthocyanin skin extract. The fermentation with the yeast Pichia guilliermondii ZIM624 showed higher potential for the production of vinylphenolic pyranoanthocyanins in comparison to artificial ageing at 30 °C. The results show a 50-fold higher yield of malvidin-3-O-glucoside-4-vinylphenol obtained by fermentation in comparison to artificial ageing. In contrast, artificial ageing of model wine produced higher yield of vitisin A (21.3%) while fermentation with P. guilliermondii ZIM624 produced this pyranoanthocyanin to a lesser extent (1.1%). The vitisin A yield in fermentations with six other yeast strains was lower than 4%. Produced pyranoanthocyanins were isolated with semi-preparative HPLC–DAD and identified with HPLC–PDA–MS3. The color of pyranoanthocyanin methanol fractions ranged from orange to pink, to light purple. [ABSTRACT FROM AUTHOR]

Historically, yeasts from the genus Saccharomyces have been conventionally used in the production of wine and other fermented beverages. Traditionally, their main role has been the transformation of sugars into ethanol, however, research has shown that yeasts also influence wine aroma, texture, flavour and colour. In lieu of this, non-Saccharomyces yeasts, which have been considered as spoilage yeasts in the past, have been exploited as potential wine starters because they can improve the sensorial characteristics of wines. Because they are considered to be poor fermenters, mixed fermentations with Saccharomyces yeasts are applied either in a form of co-inoculation or sequential fermentation. Among wine characteristics, colour of red wines has special importance because it is the first wine characteristic perceived by the consumers. Red wine colour stems from anthocyanins, located in the grape skins that are extracted to grape must during maceration/fermentation. Various technological strategies in the winemaking process have already been employed to improve wine colour. One of them is yeast-mediated colour improvement employing a careful selection of yeast starters that can promote the synthesis of stable colour pigments pyranoanthocyanins from anthocyanins. The two most known groups of pyranoanthocyanins are vinylphenolic pyranoanthocyanins and vitisins. In comparison to anthocyanins they are less susceptible to pH, SO2 bleaching and oxygen presence. Their concentration in the wines differs according to the yeast strain used and the type of fermentation applied. Furthermore, wine colour can also be influenced by the cell wall adsorption capability of yeasts. Numerous studies have shown the positive influence of a careful selection of non-Saccharomyces yeast in promoting stable pigments synthesis in the production of wine. In this review, we discuss how application of different yeast species - Saccharomyces and non-Saccharomyces can enhance wine colour through different fermentation strategies applied. [ABSTRACT FROM AUTHOR]

Saccharomyces cerevisiae and its sibling species Saccharomyces paradoxus are known to inhabit temperate arboreal habitats across the globe. Despite their sympatric distribution in the wild, S. cerevisiae is predominantly associated with human fermentations. The apparent ecological differentiation of these species is particularly striking in Europe where S. paradoxus is abundant in forests and S. cerevisiae is abundant in vineyards. However, ecological differences may be confounded with geographic differences in species abundance. To compare the distribution and abundance of these two species we isolated Saccharomyces strains from over 1200 samples taken from vineyard and forest habitats in Slovenia. We isolated numerous strains of S. cerevisiae and S. paradoxus, as well as a small number of Saccharomyces kudriavzevii strains, from both vineyard and forest environments. We find S. cerevisiae less abundant than S. paradoxus on oak trees both within and outside the vineyard, but more abundant on grapevines and associated substrates. Analysis of the uncultured microbiome shows, that both S. cerevisiae and S. paradoxus are rare species in soil and bark samples, but can be much more common in grape must. In contrast to S. paradoxus, European strains of S. cerevisiae have acquired multiple traits thought to be important for life in the vineyard and dominance of wine fermentations. We conclude, that S. cerevisiae and S. paradoxus currently share both vineyard and non-vineyard habitats in Slovenia and we discuss factors relevant to their global distribution and relative abundance. [ABSTRACT FROM AUTHOR]

Consumer wine preferences are changing rapidly towards exotic flavours and tastes. In this work, we tested five non-conventional yeast strains for their potential to improve Ribolla Gialla wine quality. These strains were previously selected from numerous yeasts interesting as food production candidates. Sequential fermentation of Ribolla Gialla grape juice with the addition of the Saccharomyces cerevisiae T73 Lalvin industrial strain was performed. Zygosaccharomyces kombuchaensis CBS8849 and Kazachstania gamospora CBS10400 demonstrated positive organoleptic properties and suitable fermentation dynamics, rapid sugar consumption and industrial strain compatibility. At the same time, Torulaspora microellipsoides CBS6641, Dekkera bruxellensis CBS2796 and Dekkera anomala CBS77 were unsuitable for wine production because of poor fermentation dynamics, inefficient sugar consumption and ethanol production levels and major organoleptic defects. Thus, we selected strains of K. gamospora and Z. kombuchaensis that significantly improved the usually plain taste of Ribolla wine by providing additional aromatic complexity in a controlled and reproducible manner. [ABSTRACT FROM AUTHOR]

Previous studies of hypersaline environments have revealed the dominant presence of melanized yeast-like fungi and related Cladosporium spp. In this study, we focused on the genera Aspergillus and Penicillium and their teleomorphic forms. From oligotrophic and eutrophic hypersaline waters around the world, 60 different species were identified, according to their morphological characteristics and extrolite profiles. For the confirmation of five new species, additionally, sequence analysis of the internal transcribed spacer region, the partial large subunit-rDNA and the partial β-tubulin gene was performed. The species Aspergillus niger, Eurotium amstelodami and Penicillium chrysogenum were detected with the highest frequencies at all of the sampled sites; thus, they represent the pan-global stable mycobiota in hypersaline environments. Possible candidates were also Aspergillus sydowii and Eurotium herbariorum, as they were quite evenly distributed among the sampled sites, and Aspergillus candidus, which was abundant, but more locally distributed. These species and their byproducts can accumulate downstream following evaporation of brine, and they can become entrapped in the salt crystals. Consequently, marine salt used for consumption can be a potential source of food-borne fungi and their byproducts. For example, ochratoxin-A-producing species Penicillium nordicum was recovered from brine, salt and salted meat products. [ABSTRACT FROM AUTHOR]

Previous studies of fungi in polar environments have revealed a prevalence of basidiomycetous yeasts in soil and in subglacial environments of polythermal glaciers. Ascomycetous yeasts have rarely been reported from extremely cold natural environments, even though they are known contaminants of frozen foods. Using media with low water activity, we have isolated various yeast species from the subglacial ice of four glaciers from the coastal Arctic environment of Kongsfjorden, Spitzbergen, including Debaryomyces hansenii and Pichia guillermondii, with counts reaching 10 CFU L. Together with the basidiomycetes Cryptococcus liquefaciens and Rhodotorula mucilaginosa, these yeasts represent the stable core of the subglacial yeast communities. Other glacial ascomycetous species isolated included Candida parapsilosis and a putative new species that resembles Candida pseudorugosa. The archiascomycete Protomyces inouyei has seldom been detected anywhere in the world but was here recovered from ice in a glacier cave. The glacier meltwater contained only D. hansenii, whereas the seawater contained D. hansenii, Debaryomyces maramus, Pichia guilliermondii, what appears to represent a novel species resembling Candida galli and Metschnikowia bicuspidata. Only P. guilliermondii was isolated from sea ice, while snow/ice in the fjord tidal zone included C. parapsilosis, D. hansenii, P. guilliermondii and Metschnikowia zobellii. All of these isolated strains were characterized as psychrotolerant and xero/halotolerant, with the exception of P. inouyei. [ABSTRACT FROM AUTHOR]

Abstract: Six different species of the known teleomorphic food-borne xerophilic genus Eurotium were repeatedly isolated in a mycodiversity study of hypersaline waters. At salinities above 17% NaCl, E. amstelodami was detected most consistently, followed by E. repens and E. herbariorum, while E. rubrum, E. chevalieri and a potentially new species, “Eurotium halotolerans”, were detected only occasionally at lower salinities. The qualitative secondary metabolite profiles produced by Eurotium spp. from salterns were not different from those of Eurotium spp. from foods and other habitats. Spatiotemporal frequency of occurrence and in vitro determined adaptive ability of propagules to survive prolonged exposure to hypersaline conditions indicate that E. amstelodami, E. herbariorum, and E. repens contribute to the indigenous fungal community in hypersaline water environments, while E. rubrum, E. chevalieri and “E. halotolerans” are only temporal inhabitants of brine at lower salinities. [Copyright &y& Elsevier]

Until recently, it was believed that microbial communities at high salinities are dominated exclusively by Archaea and Bacteria and one eukaryotic species, the alga Dunaliella salina. Recently, it became evident that melanized fungi, so far described only in the crystallization pond of Adriatic salterns within the season of salt production, can be considered as a new group of eukaryotic halophiles. They were represented by black, yeast-like hyphomycetes: Hortaea werneckii , Phaeotheca triangularis , Trimmatostroma salinum , Aureobasidium pullulans , together with phylogenetically closely related Cladosporium species. In the present study, the distribution of the melanized fungal population in five different evaporating ponds in the Adriatic salterns [covering the entire salinity range (3-30% NaCl)] was followed throughout the year. It appeared in three peaks, at 5-8%, 10-20% and 18-25% NaCl, which correlated primarily with high nitrogen values. At the highest environmental salinities, melanized fungi represented 85-100% of the total isolated mycobiota, but with lowering salinities they were partially replaced by non-melanized fungi and, at the end of the season, with NaCl concentrations below 5%, they were detected only occasionally. Melanized fungi have been isolated from hypersaline waters on three continents, indicating that they are present globally in hypersaline waters of man-made salterns. [ABSTRACT FROM AUTHOR]