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International Journal of Food... Sep 2017Aim of this work was to study the impact of mixed cultures of Saccharomyces cerevisiae and Torulaspora delbrueckii and T. delbrueckii monoculture on the fermentation...
Aim of this work was to study the impact of mixed cultures of Saccharomyces cerevisiae and Torulaspora delbrueckii and T. delbrueckii monoculture on the fermentation process conducted on two different cocoa hybrids, PS1319 and SJ02, in Bahia, Brazil. This was performed throughout studying physico-chemical changes during the fermentation process and analyzing volatile compounds and sensory analysis of chocolates. (GTG)-PCR fingerprinting was used to type isolates at strain level allowing to assess the implantation of the starter cultures added. Resulted clusters were composed by T. delbrueckii strains isolated during the first 24h of fermentation. On the contrary, S. cerevisiae, the most strongly fermenting ethanol-tolerant species, took over the fermentation at a second stage. Quantification data of T. delbrueckii during spontaneous fermentation confirm the attitude of this species of not being so commonly involved in this process. This study also showed that the inoculum influenced the PS1319 hybrid end-product quality, changing analytic profile and sensory perception of chocolates. No big influences were recorded for SJ02 hybrid, but this may be improved. In combination with S. cerevisiae, T. delbrueckii had a positive influence on the analytical profile of chocolates. The application of starter cultures did change the aroma profile of the resulting chocolate as determined by GC-MS; in some case the differences observed had a significantly impact on the consumer perception of the chocolates.
Topics: Brazil; Cacao; Ethanol; Fermentation; Saccharomyces cerevisiae; Torulaspora; Wine
PubMed: 28641144
DOI: 10.1016/j.ijfoodmicro.2017.06.004 -
Food Research International (Ottawa,... Aug 2019
Corrigendum to 'Inoculation of Torulaspora delbrueckii as a bio-protection agent in winemaking' [Food Research International, Inoculation of Torulaspora delbrueckii as a bio-protection agent in winemaking, Volume: 107 (2018), 451-461].
PubMed: 31229112
DOI: 10.1016/j.foodres.2018.11.062 -
Current Research in Food Science 2021This study evaluated the effects of yeast extracts (YE) addition (0 % and 0.25 %, w/v) on the no-volatile and volatile compounds of spent coffee grounds (SCG)...
The potential of spent coffee grounds hydrolysates fermented with and for developing an alcoholic beverage: The yeasts growth and chemical compounds modulation by yeast extracts.
This study evaluated the effects of yeast extracts (YE) addition (0 % and 0.25 %, w/v) on the no-volatile and volatile compounds of spent coffee grounds (SCG) hydrolysates fermented with single-cultures of two non- wine yeasts, and . The added YE improved the growth of both and , especially , resulting in higher ethanol production (1.98 % vs 1.47 %, v/v) by the latter yeast. In addition, the added YE did not impact on most of the alkaloids production regardless of yeast type, while significantly decreasing the contents of chlorogenic, and caffeic acids in SCG hydrolysates fermented with . Furthermore, more odor-active compounds such as acetate esters and 2-phenylethyl alcohol were produced when YE was added, and generated significantly higher amounts of esters compared to that of . Moreover, YE addition showed a more noticeable effect on the fermentation performance of relative to that of . These findings indicated the potential of SCG hydrolysates fermented with evaluated non- yeasts and may expand the applications on utilizing SCG to develop new value-added alcoholic products.
PubMed: 34382007
DOI: 10.1016/j.crfs.2021.07.004 -
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 -
Food Microbiology Oct 2020Alcoholic fermentation (AF) and malolactic fermentation (MLF) both have significant influence on the production of black raspberry wine. In this study, three microbes...
Alcoholic fermentation (AF) and malolactic fermentation (MLF) both have significant influence on the production of black raspberry wine. In this study, three microbes associated with AF and MLF including S. cerevisiae, T. delbrueckii and O. oeni were used to investigate their combined effect on basic compositional, volatile and sensory property of black raspberry wine, and four fermentation trials including single S. cerevisiae inoculation plus spontaneous MLF (BSU) and controlled MLF with O. oeni (BSO), sequential culture of T. delbrueckii and S. cerevisiae plus spontaneous MLF (BTSU) and controlled MLF (BTSO) were tested and compared. Fermentation results showed MLF in BSU, BSO and BTSO were successful, with respective period of 40, 25 and 23 days, whereas a stuck MLF occurred in BTSU. Volatile compounds were determined by HS-GC-IMS method, with a total of 45 aromas identified. BTSO was distinguished by a significant higher signal intensity of many fruity esters and a lower production of several alcohols and terpenes, which was in agreement with its perception result of strong 'fruity' and slight note of 'solvent' and 'herbaceous' during quantitative descriptive analysis. On the contrary, BSU was found to reinforce the synthesis of most detected volatiles, resulting in the enhancement of both beneficial and off-flavour compounds, therefore scoring lower in the 'global aroma' descriptor. Principal component analysis showed BSU and BSO were similar in the volatile composition, whereas BTSO was quite different. Overall, BTSO had greater potential to be used in the production of black raspberry wine.
Topics: Batch Cell Culture Techniques; Fermentation; Kinetics; Lactic Acid; Malates; Oenococcus; Rubus; Saccharomyces cerevisiae; Sensation; Torulaspora; Volatile Organic Compounds; Wine
PubMed: 32539970
DOI: 10.1016/j.fm.2020.103551 -
Brazilian Journal of Microbiology :... Sep 2022The objective of this work was to evaluate the microencapsulation feasibility of Saccharomyces cerevisiae CCMA 0543 and Torulaspora delbrueckii CCMA 0684 in three...
The objective of this work was to evaluate the microencapsulation feasibility of Saccharomyces cerevisiae CCMA 0543 and Torulaspora delbrueckii CCMA 0684 in three different compositions of wall material by spray-dryer. The yeasts (10 CFU mL) were microencapsulated separately using maltodextrin (15%), maltodextrin (15%) with sucrose (2%), or maltose (2%) as wall material. The viability was evaluated for 6 months at two different temperatures (7 and 25 °C). The yield, cell viability after spray drying, and characterization of the microcapsules were performed. Results indicate that cell viability ranged between 94.06 and 97.97%. After 6 months, both yeasts stored at 7 °C and 25 °C presented 10 and 10 CFU mL, respectively. Regarding Fourier-transform infrared spectroscopy analysis, all microencapsulated yeasts presented typical spectra footprints of maltodextrin. After 6 months of storage, S. cerevisiae CCMA 0543 obtained a 10.8% increase in cell viability using maltodextrin with maltose as wall material compared to maltodextrin and maltodextrin with sucrose. However, T. delbrueckii CCMA 0684 obtained a 13.5% increase in cell viability using only maltodextrin. The study showed that maltodextrin as a wall material was efficient in the microencapsulation of yeasts. It is possible to assume that maltose incorporation increased the cell viability of S. cerevisiae CCMA 0543 during storage.
Topics: Coffee; Fermentation; Maltose; Saccharomyces cerevisiae; Spray Drying; Sucrose; Torulaspora
PubMed: 35676493
DOI: 10.1007/s42770-022-00776-4 -
Foods (Basel, Switzerland) Jun 2022This study investigated the spoilage potential of yeast strains (Km1, Km2 and Km3) Pk1 and Td1 grown in skyr in cold storage. Yeast strains were isolated from skyr and...
This study investigated the spoilage potential of yeast strains (Km1, Km2 and Km3) Pk1 and Td1 grown in skyr in cold storage. Yeast strains were isolated from skyr and identified by sequencing of the 26S rRNA gene. yeasts were grown in skyr to high numbers, generating large amounts of volatile organic compounds (VOC) associated with off-flavours, among them were alcohols (3-methyl-1-butanol, 2-methyl-1-propanol and 1-hexanol), esters (ethyl acetate and 3-methylbutyl acetate) and aldehydes (hexanal, methylbutanal and methylpropanal). Growth of Pk1 led to moderate increases in several alcohols and esters (mostly, 3-methyl-1-butanol and ethyl acetate), whereas only minor shifts in VOCs were associated with Td2. The levels of the key aroma compounds, diacetyl and acetoin, were significantly decreased by all strains and Pk1. In contrast to the other yeast species, was able to utilize lactose, producing ethanol and carbon dioxide. Based on the overall results, was characterised by the highest spoilage potential. The study revealed the differences between the yeast species in fermentative and spoilage activities, and clarified the role of yeast metabolites for off-flavour formation and quality defects in skyr during cold storage.
PubMed: 35741978
DOI: 10.3390/foods11121776 -
Food Chemistry Jan 2024In this work, three mannoprotein extracts were obtained from T. delbrueckii by enzymatic and chemical treatments. The obtained mannoprotein extracts showed important...
In this work, three mannoprotein extracts were obtained from T. delbrueckii by enzymatic and chemical treatments. The obtained mannoprotein extracts showed important differences in their molecular weight distribution and monosaccharide composition, although no significant differences were found in their protein content. In order to evaluate the possible influence of mannoprotein characteristics in the interaction with flavanols, mannoprotein-flavanol interactions were studied by HPLC-DAD-MS and ITC. The results obtained indicate that the mannoprotein extracts were able to precipitate flavanols to a different extent. Furthermore, the degree of flavanol precipitation seemed not to be related to the affinity of the interaction but to the type of intermolecular forces. In this sense, a higher proportion of hydrogen bonding could favor a greater crosslinking between aggregates promoting flavanol precipitation. This, in turn, could be related to the MP characteristics since the presence of β-glucan moieties might have an effect on the formation of hydrogen bonds.
Topics: Torulaspora; Wine; Polyphenols; Plant Extracts; Fermentation
PubMed: 37536068
DOI: 10.1016/j.foodchem.2023.137044 -
International Journal of Food... Nov 2023Progress in oenological biotechnology now makes it possible to control alcoholic (AF) and malolactic (MLF) fermentation processes for the production of wines. Key...
Comparative study of inoculation strategies of Torulaspora delbrueckii and Saccharomyces cerevisiae on the performance of alcoholic and malolactic fermentations in an optimized synthetic grape must.
Progress in oenological biotechnology now makes it possible to control alcoholic (AF) and malolactic (MLF) fermentation processes for the production of wines. Key factors in controlling these processes and enhancing wine quality include the use of selected strains of non-Saccharomyces species, Saccharomyces cerevisiae, and Oenococcus oeni, as well as the method of inoculation (co-inoculation or sequential) and the timing of inoculation. In the present work, we investigated the effects of different inoculation strategies of two Torulaspora delbrueckii (Td-V and Td-P) strains followed by S. cerevisiae. Times (two, four, and six days) and types (co-inoculation and sequential) of inoculation were evaluated on the AF of a synthetic grape must. Furthermore, this synthetic medium was optimized by adding linoleic acid and β-sitosterol to simulate the natural grape must and facilitate reproducible results in potential assays. Subsequently, the wines obtained were inoculated with two strains of Oenococcus oeni to carry out MLF. Parameters after AF were analysed to observe the impact of wine composition on the MLF performance. The results showed that the optimization of the must through the addition of linoleic acid and β-sitosterol significantly enhanced MLF performance. This suggests that these lipids can positively impact the metabolism of O. oeni, leading to improved MLF efficiency. Furthermore, we observed that a 4-day contact period with T. delbrueckii leads to the most efficient MLF process and contributed to the modification of certain AF metabolites, such as the reduction of ethanol and acetic acid, as well as an increase in available nitrogen. The combination of Td-P with Oo-VP41 for 4 or 6 days during MLF showed that it could be the optimal option in terms of efficiency. By evaluating different T. delbrueckii inoculation strategies, optimizing the synthetic medium and studying the effects on wine composition, we aimed to gain insights into the relationship between AF conditions and subsequent MLF performance. Through this study, we aim to provide valuable insights for winemakers and researchers in the field of wine production and will contribute to a better understanding of the complex interactions between these species in the fermentation process.
Topics: Vitis; Fermentation; Saccharomyces cerevisiae; Torulaspora; Linoleic Acid; Culture Media
PubMed: 37597274
DOI: 10.1016/j.ijfoodmicro.2023.110367 -
Journal of Bioscience and Bioengineering Jul 2020Saccharomyces cerevisiae can obtain xylose utilization capacity via integration of heterogeneous xylose reductase (XR) and xylitol dehydrogenase (XDH) genes into its...
Saccharomyces cerevisiae can obtain xylose utilization capacity via integration of heterogeneous xylose reductase (XR) and xylitol dehydrogenase (XDH) genes into its metabolic pathway, and XYL2 which encodes the XDH plays an essential role in this process. Herein, we reported that two hypothetical XYL2 genes from the multistress-tolerant yeasts of Issatchenkia orientalis and Torulaspora delbrueckii were cloned, and they encoded two XDHs, IoXyl2p and TdXyl2p, respectively, with the activities for oxidation of xylitol to xylulose. Comparative studies demonstrated that IoXyl2p and TdXyl2p, like the SsXyl2p from Scheffersomyces stipitis, were probably localized to the cytoplasm and strictly dependent on NAD rather than NADP as the cofactor for catalyzing the oxidation reaction of xylitol. IoXyl2p had the highest specific activity, maximum velocity (V), affinity to xylitol (K), and catalytic efficiency (k/K) among the three XDHs. The optimum temperature for oxidation of xylitol were at 45 °C by IoXyl2p and at 35 °C by TdXyl2p and SsXyl2p, and the optimum pH of IoXyl2p, TdXyl2p and SsXyl2p for oxidation of xylitol was 8.0, 8.5 and 7.5, respectively. Mg promoted the activities of IoXyl2p and TdXyl2p, but slightly inhibited the activity of SsXyl2p. Most metal ions had much weaker inhibition effects on IoXyl2p and TdXyl2p than SsXyl2p. IoXyl2p displayed the strongest salt resistance among the three XDHs. To summarize, IoXyl2p from I. orientalis and TdXyl2p from T. delbrueckii characterized in this study are considered to be the attractive candidates for the construction of genetically engineered S. cerevisiae for efficiently fermentation of carbohydrate in lignocellulosic hydrolysate.
Topics: Cloning, Molecular; D-Xylulose Reductase; Enzyme Stability; Fermentation; Fungal Proteins; Kinetics; Pichia; Torulaspora; Xylitol; Xylose
PubMed: 32171656
DOI: 10.1016/j.jbiosc.2020.02.012