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International Journal of Molecular... Jul 2023Hybrid formation and introgressions had a profound impact on fermentative yeasts domesticated for beer, wine and cider fermentations. Here we provide a comparative...
Hybrid formation and introgressions had a profound impact on fermentative yeasts domesticated for beer, wine and cider fermentations. Here we provide a comparative genomic analysis of a British cider yeast isolate (E1) and characterize its fermentation properties. E1 has a genome into which ~102 kb of DNA were introgressed that replaced the endogenous homologous 55 genes of chromosome XIV between and . Sequence analyses indicated that the DNA donor was either a lager yeast or a yet unidentified ancestor. Interestingly, a second introgression event added ~66 kb of DNA from to the left telomere of . This region bears high similarity with the previously described region C introgression in the wine yeast EC1118. Within this region and encode two oligopeptide transporters that promote improved nitrogen uptake from grape must in E1, as was reported for EC1118. Comparative laboratory scale grape must fermentations between the E1 and EC1118 indicated beneficial traits of faster consumption of total sugars and higher glycerol production but low acetic acid and reduced ethanol content. Importantly, the cider yeast strain produced high levels of fruity ester, including phenylethyl and isoamyl acetate.
Topics: Saccharomyces cerevisiae; Wine; Alcoholic Beverages; Fermentation; Beer; Vitis
PubMed: 37446410
DOI: 10.3390/ijms241311232 -
Microbial Biotechnology Jan 2024The potential use of Torulaspora delbrueckii as a starter culture for wine alcoholic fermentation has become a subject of interest in oenological research. The use of... (Review)
Review
The potential use of Torulaspora delbrueckii as a starter culture for wine alcoholic fermentation has become a subject of interest in oenological research. The use of this non-Saccharomyces yeast can modulate different wine attributes, such as aromatic substances, organic acids and phenolic compound compositions. Thus, the obtained wines are different from those fermented with Saccharomyces cerevisiae as the sole starter. Nevertheless, information about the possible effects of T. delbrueckii chemical modulation on subsequent malolactic fermentation is still not fully explained. In general, T. delbrueckii is related to a decrease in toxic compounds that negatively affect Oenococcus oeni and an increase in others that are described as stimulating compounds. In this work, we aimed to compile the changes described in studies using T. delbrueckii in wine that can have a potential effect on O. oeni and highlight those works that directly evaluated O. oeni performance in T. delbrueckii fermented wines.
Topics: Fermentation; Torulaspora; Wine; Saccharomyces cerevisiae; Phenols
PubMed: 37387409
DOI: 10.1111/1751-7915.14302 -
Food Chemistry Oct 2023The effects of Saccharomyces cerevisiae and Torulaspora delbrueckii on phenolic composition and sensory quality were characterized in the production of alcoholic...
The effects of Saccharomyces cerevisiae and Torulaspora delbrueckii on phenolic composition and sensory quality were characterized in the production of alcoholic beverages from selected pear cultivars with diverse biochemical characteristics. The fermentation process generally affected the phenolic composition by increasing the contents of hydroxycinnamic acids and flavan-3-ols and reducing the levels of hydroxybenzoic acids, procyanidins, and flavonols. Although the phenolic compositions and sensory properties of pear beverages depended primarily on pear cultivar selection, the applied yeast strains also played important roles in beverage quality. Fermentation with T. delbrueckii resulted in higher caffeoylquinic acid and quercetin-3-O-glucoside contents, higher rated intensities of 'cooked pear' and 'floral' odors and a sweeter taste than fermentation with S. cerevisiae. Moreover, higher concentrations of hydroxybenzoic acids, hydroxycinnamic acids, and flavonols correlated closely with astringency perception. Applying T. delbrueckii strains and breeding novel pear cultivars are important approaches to produce fermented beverages of high quality.
Topics: Saccharomyces cerevisiae; Torulaspora; Pyrus; Wine; Plant Breeding; Phenols; Fermentation; Hydroxybenzoates
PubMed: 37148850
DOI: 10.1016/j.foodchem.2023.136184 -
International Journal of Food... Aug 2023In the present study, the physicochemical (pH, water activity, moisture content, salt concentration) classical plate counts (total viable counts, yeasts, lactic acid...
In the present study, the physicochemical (pH, water activity, moisture content, salt concentration) classical plate counts (total viable counts, yeasts, lactic acid bacteria, Staphylococcus aureus, Pseudomonas spp., Enterobacteriaceae) and amplicon sequencing of naturally black dry-salted olives obtained from different retail outlets of the Greek market were investigated. According to the results, the values of the physicochemical characteristics presented great variability among the samples. Specifically, pH and water activity (a) values ranged between 4.0 and 5.0, as well as between 0.58 and 0.91, respectively. Moisture content varied between 17.3 and 56.7 % (g ΗΟ/100 g of olive pulp), whereas salt concentration ranged from 5.26 to 9.15 % (g NaCl/100 g of olive pulp). No lactic acid bacteria, S. aureus, Pseudomonas spp. and Enterobacteriaceae were detected. The mycobiota consisted of yeasts that were further characterized and identified by culture-dependent (rep-PCR, ITS-PCR, and RFLP) and amplicon target sequencing (ATS). Pichia membranifaciens, Candida sorbosivorans, Citeromyces nyonsensis, Candida etchelsii, Wickerhamomyces subpelliculosus, Candida apicola, Wickerhamomyces anomalus, Torulaspora delbrueckii and Candida versatilis were the dominant species according to ITS sequencing (culture-dependent), while ATS revealed the dominance of C. etchelsii, Pichia triangularis, P. membranifaciens, and C. versatilis among samples. The results of this study demonstrated considerable variability in quality attributes among the different commercial samples of dry-salted olives, reflecting a lack of standardization in the processing of this commercial style. However, the majority of the samples were characterized by satisfactory microbiological and hygienic quality and complied with the requirements of the trade standard for table olives of the International Olive Council (IOC) for this processing style in terms of salt concentration. In addition, the diversity of yeast species was elucidated for the first time in commercially available products, increasing our knowledge on the microbial ecology of this traditional food. Further investigation into the technological and multifunctional traits of the dominant yeast species may result in better control during dry-salting and enhance the quality and shelf-life of the final product.
Topics: Sodium Chloride; Olea; Staphylococcus aureus; Greece; Food Microbiology; Yeasts; Enterobacteriaceae; Fermentation
PubMed: 37120943
DOI: 10.1016/j.ijfoodmicro.2023.110226 -
Food Microbiology Aug 2023Contamination of white-brined cheeses (WBCs) with yeasts is of major concern in the dairy industry. This study aimed to identify yeast contaminants and characterize...
Contamination of white-brined cheeses (WBCs) with yeasts is of major concern in the dairy industry. This study aimed to identify yeast contaminants and characterize their succession in white-brined cheese during a shelf-life of 52 weeks. White-brined cheeses added herbs (WBC1) or sundried tomatoes (WBC2) were produced at a Danish dairy and incubated at 5 °C and 10 °C. An increase in yeast counts was observed for both products within the first 12-14 weeks of incubation and stabilized afterwards varying in a range of 4.19-7.08 log CFU/g. Interestingly, higher incubation temperature, especially in WBC2, led to lower yeast counts, concurrently with higher diversity of yeast species. Observed decrease in yeast counts was, most likely, due to negative interactions between yeast species leading to growth inhibition. In total, 469 yeast isolates from WBC1 and WBC2 were genotypically classified using the (GTG)-rep-PCR technique. Out of them, 132 representative isolates were further identified by sequencing the D1/D2 domain of the 26 S rRNA gene. Predominant yeast species in WBCs were Candida zeylanoides and Debaryomyces hansenii, while Candida parapsilosis, Kazachstania bulderi, Kluyveromyces lactis, Pichia fermentans, Pichia kudriavzevii, Rhodotorula mucilaginosa, Torulaspora delbrueckii, and Wickerhamomyces anomalus were found in lower frequency. Heterogeneity of yeast species in WBC2 was generally larger compared to WBC1. This study indicated that, along with contamination levels, taxonomic heterogeneity of yeasts is an important factor influencing yeast cell counts, as well as product quality during storage.
Topics: Cheese; Yeasts; Polymerase Chain Reaction
PubMed: 37098422
DOI: 10.1016/j.fm.2023.104266