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International Journal of Food... Nov 2022The current use of non-Saccharomyces yeasts in mixed fermentations increases the relevance of the interactions between yeast species. In this work, the interactions...
The current use of non-Saccharomyces yeasts in mixed fermentations increases the relevance of the interactions between yeast species. In this work, the interactions between Saccharomyces cerevisiae and Torulaspora delbrueckii were analyzed. For this purpose, fermentations with and without contact between strains of those yeast species were performed in synthetic must. Fermentation kinetics, yeast growth and dynamics were measured over time. Additionally, the effects of nitrogen and other nutrient supplementations on the mixed fermentations were determined. Our results showed that S. cerevisiae did not always dominate the sequential fermentations, and experiments without yeast contact (in which T. delbrueckii cells were removed from the medium before inoculating S. cerevisiae at 48 h) resulted in stuck fermentations except when the inoculum size was increased (from 2 × 10 to 10 cells/mL) or there was a supplementation of thiamine, zinc and amino acids at the same concentration as initially found in the synthetic must. Our findings highlight the importance of inoculum size and ensuring the availability of enough micronutrients for all yeast species, especially in sequential fermentations.
Topics: Amino Acids; Fermentation; Micronutrients; Nitrogen; Saccharomyces cerevisiae; Thiamine; Torulaspora; Wine; Zinc
PubMed: 36084391
DOI: 10.1016/j.ijfoodmicro.2022.109915 -
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 -
Foods (Basel, Switzerland) Jan 2023Non-Saccharomyces (NS) yeasts are gaining popularity in modern winemaking for improving wine quality. Climate change is one of the biggest challenges winegrowing now...
Non-Saccharomyces (NS) yeasts are gaining popularity in modern winemaking for improving wine quality. Climate change is one of the biggest challenges winegrowing now faces in warm regions. Here, Lachancea thermotolerans LtS1 and Torulaspora delbrueckii TdS6 combined with Saccharomyces cerevisiae ScS13 isolated from Assyrtiko grapes from Santorini island were evaluated in grape must fermentation with the aim to mitigate major consequences of temperature rise. Different inoculation protocols were evaluated, including simultaneous and sequential mixed-strain inoculations, displaying significant variation in the chemical and kinetic characteristics. Both LtS1 and TdS6 could raise the titratable acidity (TA). TdS6 also reduced the volatile acidity (VA) and was thus chosen for further evaluation in microvinifications and pilot-scale fermentations. Consistent with lab-scale trials, sequential inoculation exhibited the longest persistence of TdS6 resulting in minimum VA levels. Diethyl succinate, ethyl propanoate, and ethyl isobutyrate were significantly increased in sequential inoculations, although a decline in the net total ester content was observed. On the other hand, significantly higher levels of TA, succinic acid, and 2-methylpropanoic were associated with sequential inoculation. The overall performance of TdS6 coupled with a high compatibility with S. cerevisiae suggests its use in the fermentation of Santorini-Assyrtiko or other high sugar musts for the production of structured dry or sweet wines.
PubMed: 36613407
DOI: 10.3390/foods12010191 -
Molecules (Basel, Switzerland) Apr 2024The effects of different fermentation methods utilizing 1004 and 32169 on the physicochemical properties, organic acid content, polyphenol and flavonoid...
The effects of different fermentation methods utilizing 1004 and 32169 on the physicochemical properties, organic acid content, polyphenol and flavonoid concentrations, antioxidant activity, and volatile aroma compounds of Huaniu apple cider were investigated in this study. Employing methods of single inoculation, co-inoculation, and sequential inoculation, it was found that sequential fermentation exhibited strong fermentative power in the initial stages, effectively reducing the content of soluble solids and achieving a balanced composition of malic, succinic, and citric acids while maintaining a lower titratable acidity. Sequential inoculation was observed to significantly enhance the total polyphenols and flavonoids, as well as the antioxidant capacity ( < 0.05). Specifically, in the synthesis of volatile aroma compounds, sequential inoculation significantly enhanced the richness and diversity of the Huaniu apple cider's aromas, particularly in terms of the concentration of ester compounds ( < 0.05). Principal component analysis further confirmed the superiority of sequential inoculation in terms of aroma component diversity and richness. The findings of this study suggest that sequential inoculation of fermentation with non- and is an effective strategy for optimizing the flavor characteristics of Huaniu apple cider, offering valuable theoretical support and practical guidance for enhancing cider quality and fostering the development of new products.
Topics: Saccharomyces cerevisiae; Malus; Fermentation; Torulaspora; Volatile Organic Compounds; Flavoring Agents; Polyphenols; Antioxidants; Flavonoids; Odorants
PubMed: 38675570
DOI: 10.3390/molecules29081750 -
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 -
Microorganisms Apr 2023Drinking wine is a processed beverage that offers high nutritional and health benefits. It is produced from grape must, which undergoes fermentation by yeasts (and... (Review)
Review
Drinking wine is a processed beverage that offers high nutritional and health benefits. It is produced from grape must, which undergoes fermentation by yeasts (and sometimes lactic acid bacteria) to create a product that is highly appreciated by consumers worldwide. However, if only one type of yeast, specifically , was used in the fermentation process, the resulting wine would lack aroma and flavor and may be rejected by consumers. To produce wine with a desirable taste and aroma, non- yeasts are necessary. These yeasts contribute volatile aromatic compounds that significantly impact the wine's final taste. They promote the release of primary aromatic compounds through a sequential hydrolysis mechanism involving several glycosidases unique to these yeasts. This review will discuss the unique characteristics of these yeasts (, , , , , , , , and others) and their impact on wine fermentations and co-fermentations. Their existence and the metabolites they produce enhance the complexity of wine flavor, resulting in a more enjoyable drinking experience.
PubMed: 37317152
DOI: 10.3390/microorganisms11051178 -
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 -
Food Chemistry May 2023To investigate the effects of mixed fermentation with T. delbrueckii on aroma profiles of blueberry fermented beverage, five fermentations were conducted: monoculture of...
To investigate the effects of mixed fermentation with T. delbrueckii on aroma profiles of blueberry fermented beverage, five fermentations were conducted: monoculture of T. delbrueckii and S. cerevisiae, respectively; co-inoculation of two strains; sequential inoculation of two strains at time intervals of 24 h and 48 h, respectively. Compared with pure S. cerevisiae fermentation, ethanol level was decreased by up to 1.1% vol., while total anthocyanins were increased by 27.7%-85.0% in mixed fermentations. Marker aroma compounds in different fermentations with relative odor activity values higher than 1were identified. T. delbrueckii significantly decreased volatile acid content (especially acetic acid) by 22.2%-83.3%. Ethyl 3-methylbutanoate, ethyl hexanoate and ethyl octanoate, in pure T. delbrueckii fermentation were significantly decreased, while their concentrations were increased by 1.6-4.4 folds in sequential fermentations. Besides, linalool, rose oxide, benzeneacetaldehyde were significantly increased by sequential fermentation, which was associated with the enhancement of fruity and sweet notes.
Topics: Saccharomyces cerevisiae; Torulaspora; Wine; Blueberry Plants; Anthocyanins; Fermentation; Acetic Acid
PubMed: 36586265
DOI: 10.1016/j.foodchem.2022.135284 -
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 -
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