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Food Chemistry Feb 2022Black currants (Ribes nigrum) were fermented with Saccharomyces and non-Saccharomyces yeasts without added sugar to yield low-ethanol-content beverages. The effects of...
Comparison of volatile compounds and sensory profiles of alcoholic black currant (Ribes nigrum) beverages produced with Saccharomyces, Torulaspora, and Metschnikowia yeasts.
Black currants (Ribes nigrum) were fermented with Saccharomyces and non-Saccharomyces yeasts without added sugar to yield low-ethanol-content beverages. The effects of yeasts on the volatile compounds and sensory characteristics were analysed by HS-SPME-GC-MS, GC-O, and generic descriptive analysis. Ninety-eight volatile compounds were identified from the black currant juice and fermented beverages. Significant increases in the contents of esters (131 %), higher alcohols (391 %), and fatty acids (not present in juice sample) compared to initial juice were observed depending on the yeasts used. GC-O analysis revealed the higher impact of esters on the sensory properties of Saccharomyces bayanus-fermented beverage compared to the Torulaspora delbrueckii-fermented beverage. In the sensory evaluation, non-Saccharomyces yeasts resulted in a higher 'black currant odour'. However, all beverages were intensely sour, which can be a significant challenge in the development of alcoholic berry beverages.
Topics: Alcoholic Beverages; Fermentation; Metschnikowia; Ribes; Saccharomyces; Torulaspora; Wine; Yeasts
PubMed: 34520974
DOI: 10.1016/j.foodchem.2021.131049 -
International Journal of Molecular... Dec 2021The killer phenotype of (Td) and (Sc) is encoded in the genome of medium-size dsRNA viruses (V-M). Killer strains also contain a helper large size (4.6 kb) dsRNA virus...
The killer phenotype of (Td) and (Sc) is encoded in the genome of medium-size dsRNA viruses (V-M). Killer strains also contain a helper large size (4.6 kb) dsRNA virus (V-LA) which is required for maintenance and replication of V-M. Another large-size (4.6 kb) dsRNA virus (V-LBC), without known helper activity to date, may join V-LA and V-M in the same yeast. Kbarr1 killer strain contains the killer virus Mbarr1 in addition to two L viruses, TdV-LAbarr1 and TdV-LBCbarr1. In contrast, the Kbarr2 killer strain contains two M killer viruses (Mbarr1 and M1) and a LBC virus (TdV-LBCbarr2), which has helper capability to maintain both M viruses. The genomes of TdV-LBCbarr1 and TdV-LBCbarr2 were characterized by high-throughput sequencing (HTS). Both RNA genomes share sequence identity and similar organization with their ScV-LBC counterparts. They contain all conserved motifs required for translation, packaging, and replication of viral RNA. Their Gag-Pol amino-acid sequences also contain the features required for cap-snatching and RNA polymerase activity. However, some of these motifs and features are similar to those of LA viruses, which may explain that at least TdV-LBCbarr2 has a helper ability to maintain M killer viruses. Newly sequenced ScV-LBC genomes contained the same motifs and features previously found in LBC viruses, with the same genome location and secondary structure. Sequence comparison showed that LBC viruses belong to two clusters related to each species of yeast. No evidence for associated co-evolution of specific LBC with specific M virus was found. The presence of the same M1 virus in and raises the possibility of cross-species transmission of M viruses.
Topics: Amino Acid Sequence; Base Sequence; Capsid; Double Stranded RNA Viruses; Genome, Viral; Helper Viruses; RNA, Double-Stranded; RNA, Viral; Saccharomyces cerevisiae; Torulaspora; Wine
PubMed: 34948288
DOI: 10.3390/ijms222413492 -
Molecular Ecology May 2023Microbe domestication has a major applied relevance but is still poorly understood from an evolutionary perspective. The yeast Torulaspora delbrueckii is gaining...
Microbe domestication has a major applied relevance but is still poorly understood from an evolutionary perspective. The yeast Torulaspora delbrueckii is gaining importance for biotechnology but little is known about its population structure, variation in gene content or possible domestication routes. Here, we show that T. delbrueckii is composed of five major clades. Among the three European clades, a lineage associated with the wild arboreal niche is sister to the two other lineages that are linked to anthropic environments, one to wine fermentations and the other to diverse sources including dairy products and bread dough (Mix-Anthropic clade). Using 64 genomes we assembled the pangenome and the variable genome of T. delbrueckii. A comparison with Saccharomyces cerevisiae indicated that the weight of the variable genome in the pangenome of T. delbrueckii is considerably smaller. An association of gene content and ecology supported the hypothesis that the Mix-Anthropic clade has the most specialized genome and indicated that some of the exclusive genes were implicated in galactose and maltose utilization. More detailed analyses traced the acquisition of a cluster of GAL genes in strains associated with dairy products and the expansion and functional diversification of MAL genes in strains isolated from bread dough. In contrast to S. cerevisiae, domestication in T. delbrueckii is not primarily driven by alcoholic fermentation but rather by adaptation to dairy and bread-production niches. This study expands our views on the processes of microbe domestication and on the trajectories leading to adaptation to anthropic niches.
Topics: Saccharomyces cerevisiae; Torulaspora; Domestication; Fermentation; Wine
PubMed: 35298044
DOI: 10.1111/mec.16428 -
Journal of Dairy Science Dec 2023The possible contribution of brine-derived microflora to the sensory attributes of cheese is still a rather unexplored field. In this study, 365 bacteria and 105 yeast...
The possible contribution of brine-derived microflora to the sensory attributes of cheese is still a rather unexplored field. In this study, 365 bacteria and 105 yeast strains isolated from 11 cheese brines were qualitatively tested for proteolytic and lipolytic activities, and positive strains were identified by sequencing. Among bacteria, Staphylococcus equorum was the most frequent, followed by Macrococcus caseolyticus and Corynebacterium flavescens. As for yeasts, Debaryomyces hansenii, Clavispora lusitaniae, and Torulaspora delbrueckii were most frequently identified. A total of 38% of bacteria and 59% of yeasts showed at least 1 of the metabolic activities tested, with lipolytic activity being the most widespread (81% of bacteria and 95% of yeasts). Subsequently 15 strains of bacteria and 10 yeasts were inoculated in a curd-based medium and assessed via headspace-solid phase microextraction coupled with gas chromatography-mass spectrometry to determine their volatilome. After a 30-d incubation at 12°C, most strains showed a viability increase of about 2 log cfu/mL, suggesting good adaptability to the cheese environment. A total of 26 compounds were detected in the headspace, carbonyl compounds and alcohols being the major contributors to the volatile profile of the curd-based medium. Multivariate analysis was carried out to elucidate the overall differences in volatiles produced by selected strains. Principal component analysis and hierarchical clustering analysis demonstrated that the brine-related microorganisms were separated into 3 different groups, suggesting their different abilities to produce volatile compounds. Some of the selected strains have been shown to have interesting aromatic potential and to possibly contribute to the sensory properties of cheese.
Topics: Animals; Salts; Yeasts; Bacteria; Gas Chromatography-Mass Spectrometry; Cheese
PubMed: 37641243
DOI: 10.3168/jds.2022-23051 -
MSystems Aug 2022Traditional fermentation processes are driven by complex fungal microbiomes. However, the exact means by which fungal diversity affects fermentation remains unclear. In...
Traditional fermentation processes are driven by complex fungal microbiomes. However, the exact means by which fungal diversity affects fermentation remains unclear. In this study, we systematically investigated the diversity of a fungal community and its functions during the multibatch fermentation process. Metabolomics analysis showed that the metabolic profiles of the were enhanced with an increase in the fermentation time, as determined from the characteristic volatile flavors. High-throughput sequencing technology revealed that the major fungal species involved in sauce-flavor fermentation are sp. (41.75%, average relative abundance), sp. (13.07%), thermophilic species (9.16%), sp. (6.80%), Aspergillus sp. (4.69%), sp. (3.76%), sp. (3.74%), and Zygosaccharomyces sp. (1.41%). In addition, the fungal diversity increased as the number of fermentation batches increased. Moreover, the increased fungal diversity contributed to the modularity of the fungal communities, wherein sp., sp., and sp. maintained the stability of the fungal community. In addition, metatranscriptomics sequencing technologies were used to reconstruct the key metabolic pathways during fermentation, and it was found that the increased microbial diversity significantly promoted glucose-mediated carbon metabolism. Finally, functional gene analysis showed that functional microorganisms, such as Zygosaccharomyces and , can enhance fermentation as a result of the high expression of pyruvate decarboxylase and propanol-preferring alcohol dehydrogenase during the metabolism of pyruvate. These results indicate that fungal biodiversity can be exploited to enhance fermentation-based processes via network interactions and metabolism during multiple-batch fermentation. Biodiversity and network interactions act simultaneously on the microbial community structure in the fermentation process, thereby rendering the microbiome dynamics challenging to manage and predict. Understanding the complex fermentation community and its relationship to community functions is therefore important in the context of developing improved fermentation biotechnology systems. Our work demonstrates that multiple-batch fermentation steps increase microbial diversity and promote community stability. Crucially, the enhanced modularity in the microbial network increases the metabolism of flavor compounds and ethanol. This study highlights the power of biodiversity and network interactions in regulating the function of the microbiome in food fermentation ecosystems.
Topics: Fermentation; Microbiota; Carbohydrate Metabolism; Mycobiome; Pichia; Saccharomyces
PubMed: 35862822
DOI: 10.1128/msystems.00401-22 -
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 -
Food Microbiology Sep 2020Torulaspora delbrueckii and Saccharomyces cerevisiae are yeast species found concurrently in wine. In order to commence fermentation, they adapt to the initial harsh... (Comparative Study)
Comparative Study
Torulaspora delbrueckii and Saccharomyces cerevisiae are yeast species found concurrently in wine. In order to commence fermentation, they adapt to the initial harsh environment, maintaining cellular homeostasis and promoting metabolism. These actions involve an intricate regulation of stress tolerance, growth and metabolic genes. Their phenotypes are influenced by the fermentation environment and physiological state of the cell, but such gene-environment interactions are poorly understood. This study aimed to compare the cell physiology of the two species, through genome-wide analysis of gene expression, coupling Oxford Nanopore MinION and Illumina Hiseq sequencing platforms. The early transcriptional responses to stress, nutrients and cell-to-cell communication were analysed. Particular attention was given to the fundamental gene modulations, leading to an understanding of the physiological changes needed to maintain cellular homeostasis, exit the quiescent state and establish dominance in the fermentation. Our findings suggest the existence of species-specific adaptation strategies in response to growth in a high sugar synthetic grape juice medium.
Topics: Adaptation, Physiological; Culture Media; Fermentation; Gene Expression; Genome, Fungal; Glucose; Saccharomyces cerevisiae; Torulaspora; Vitis; Wine
PubMed: 32336354
DOI: 10.1016/j.fm.2020.103463 -
Revista Argentina de Microbiologia 2021Yeasts play a crucial role in brewing. During fermentation, besides ethanol and carbon dioxide, yeasts produce a considerable number of organic compounds, which are... (Review)
Review
Yeasts play a crucial role in brewing. During fermentation, besides ethanol and carbon dioxide, yeasts produce a considerable number of organic compounds, which are essential for beer flavor. In particular, Saccharomyces cerevisiae and Saccharomyces pastorianus are traditionally used in the production of ale and lager beers, respectively. Nowadays, the continuous growth of the craft beer market motivates the production of differential and innovative beers; leading specialists and brewers focus on non-conventional yeasts as tools for new product development. In this work, we describe the potential application of non-conventional yeast species such as those of the genera Brettanomyces, Torulaspora, Lachancea, Wickerhamomyces, Pichia and Mrakia in the craft brewing industry, as well as non-traditional brewing yeasts of the Saccharomyces genus. Furthermore, the fermentation conditions of these non-conventional yeasts are discussed, along with their abilities to assimilate and metabolize diverse wort components providing differential characteristics to the final product. In summary, we present a comprehensive review of the state-of-the-art of non-conventional yeasts, which is highly relevant for their application in the production of novel craft beers including flavored beers, non-alcoholic beers, low-calorie beers and functional beers.
Topics: Beer; Fermentation; Flavoring Agents; Pichia; Saccharomyces cerevisiae; Yeasts
PubMed: 33674169
DOI: 10.1016/j.ram.2021.01.003 -
Food Research International (Ottawa,... Dec 2023All coffee production stages occur in a microbiome, which is generally composed of bacteria, yeasts, and filamentous fungi. The use of starter cultures in post-harvest...
All coffee production stages occur in a microbiome, which is generally composed of bacteria, yeasts, and filamentous fungi. The use of starter cultures in post-harvest processing stages is an interesting alternative, since they promote faster removal of mucilage and incorporation of compounds that improve sensory quality, which can result in diverse sensory attributes for the beverage. This study was therefore developed with the objective of evaluating the effect of the following processing procedures on the chemical and sensory characteristics of the coffee beverage: first, fermentation of coffee fruit of the yellow Catucaí variety of Coffea arabica with indigenous microorganisms, followed by inoculation of the starter culture Torulaspora delbrueckii CCMA 0684 during the drying stage. The fruit was divided into two lots, which were differentiated by a natural fermentation process before drying began. The starter culture was inoculated on the coffee at different times during the drying process: at 0 h, 24 h, 48 h, or 72 h after drying began. The sensory attributes, the volatile compound composition of the roasted beans, the organic acid profile, the bioactive compounds, and the fatty acid profile of the green coffee beans were analyzed. The fatty acid and bioactive compound content showed little variation among treatments. Analysis of volatile compounds and organic acids and evaluation of sensory attributes made it possible to distinguish the two treatments. We conclude that natural fermentation of coffee fruit improve the chemical and sensory quality of the coffee beverage. The effect of natural fermentation may be before inoculation of the starter cultures or even during drying.
Topics: Torulaspora; Fermentation; Yeast, Dried; Fungi; Fatty Acids
PubMed: 37986481
DOI: 10.1016/j.foodres.2023.113632 -
Food Chemistry Nov 2021The study aimed to improve the quality of dry-processed coffee grown at low altitudes through yeast inoculation, using three species (Saccharomyces cerevisiae CCMA 0543,...
The study aimed to improve the quality of dry-processed coffee grown at low altitudes through yeast inoculation, using three species (Saccharomyces cerevisiae CCMA 0543, Torulaspora delbrueckii CCMA 0684, and Candida parapsilosis CCMA 0544) singly and with co-inoculation for fermentation. Important chemical compounds and groups were analyzed by liquid and gas chromatography and Fourier-transform infrared spectroscopy (FTIR). The inoculated coffees with yeast populations around 10 cell/g obtained the highest scores, and the co-inoculation with C. parapsilosis CCMA 0544 and T. delbrueckii CCMA 0684 had the highest score in the sensory analysis (85). Different descriptors were observed in each treatment, and body, flavor, balance, and aftertaste are strongly related to C. parapsilosis CCMA 0544. The fermentation process improved the quality of low-altitude coffees, and the combination of non-Saccharomyces yeasts (C. parapsilosis CCMA 0544 and T. delbrueckii CCMA 0684) was the most indicated as starter cultures.
Topics: Altitude; Candida parapsilosis; Coffea; Coffee; Fermentation; Flavoring Agents; Saccharomyces cerevisiae; Taste; Torulaspora
PubMed: 34082390
DOI: 10.1016/j.foodchem.2021.130133