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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 -
Molecules (Basel, Switzerland) May 2023The market of non-alcoholic and low-alcohol beer has grown continuously thanks to the advocacy for healthy and responsible drinking. Non-alcoholic and low-alcohol...
The market of non-alcoholic and low-alcohol beer has grown continuously thanks to the advocacy for healthy and responsible drinking. Non-alcoholic and low-alcohol products usually possess less higher alcohols and acetates and more aldehyde off-flavors due to the manufacturing processes. The employment of non-conventional yeasts partially mitigates this problem. In this study, we used proteases to optimize the wort amino acid profile for better aroma production during yeast fermentation. The design of experiments was applied to increase the leucine molar fraction, aiming to boost 3-methylbutan-1-ol and 3-methylbutyl acetate (banana-like aromas). This led to an increase from 7% to 11% leucine in wort after protease treatment. The aroma output in the subsequent fermentation, however, was yeast-dependent. An 87% increase of 3-methylbutan-1-ol and a 64% increase of 3-methylbutyl acetate were observed when was used. When was employed, higher alcohols and esters from valine and isoleucine were increased: 58% more of 2-methylpropyl acetate, 67% more of 2-methylbutan-1-ol, and 24% more of 2-methylbutyl acetate were observed. Conversely, 3-methylbutan-1-ol decreased by 58% and 3-methylbutyl acetate largely remained the same. Apart from these, the amounts of aldehyde intermediates were increased to a varying extent. The impact of such increases in aromas and off-flavors on the perception of low-alcohol beer remains to be evaluated by sensory analysis in future studies.
Topics: Alcohols; Beer; Leucine; Peptide Hydrolases; Yeasts; Fermentation; Endopeptidases; Aldehydes; Acetates
PubMed: 37298894
DOI: 10.3390/molecules28114419 -
Foods (Basel, Switzerland) May 2023Traditional kombucha is a functional tea-based drink that has gained attention as a low or non-alcoholic beverage. The fermentation is conducted by a community of...
Traditional kombucha is a functional tea-based drink that has gained attention as a low or non-alcoholic beverage. The fermentation is conducted by a community of different microorganisms, collectively called SCOBY (Symbiotic Culture of Bacteria and Yeast) and typically consists of different acetic acid bacteria and fermenting yeast, and in some cases lactic acid bacteria that would convert the sugars into organic acids-mostly acetic acid. In this study, the effect of including a starter culture in a kombucha fermentation was investigated. additions led to a quicker accumulation of acetic acid along with the production of several acetate esters including isoamyl acetate and 2-phenethyl acetate. A subsequent tasting also noted a significant increase in the fruitiness of the kombucha. The significant contribution to the aroma content shows the promise of this yeast in future microbial formulations for kombucha fermentations.
PubMed: 37238757
DOI: 10.3390/foods12101938 -
Foods (Basel, Switzerland) Apr 2023Pellicle formation is the most typical characteristic of deteriorating fermented vegetable products. essential oil (PEO) is widely used as a useful natural...
Pellicle formation is the most typical characteristic of deteriorating fermented vegetable products. essential oil (PEO) is widely used as a useful natural preservative. However, few studies have addressed the antifungal activity and mechanism of PEO in pellicle formation microorganisms, and it is still unclear whether it can inhibit pellicle formation and affect its volatile compounds in Sichuan pickles. The current study showed that PEO can inhibit pellicle formation during fermentation of Sichuan pickles as it had significant antifungal activity against the pellicle formation microorganisms SH1 and SH2. The minimum inhibitory concentration (MIC) of PEO against SH1 and SH2 was determined to be 0.4 μL/mL, and the minimum fungicidal concentrations (MFCs) were 1.6 μL/mL and 0.8 μL/mL, respectively. The antifungal mechanism was activated as a result of damage to the cell membrane, an increase in the cell permeability, a decrease in the mitochondrial membrane potential, and the inhibition of ATPase activity. Meanwhile, the addition of PEO to Sichuan pickles can enrich the profiles of volatile compounds during fermentation, including limonene, myrcene, 1,8-cineole, linalool, perilla ketone, heptanal, hexanal, α-thujone and β-terpineol and thus improve the overall sensory acceptability. These results indicated that PEO has the potential to be used as a novel food preservative to control pellicle formation in fermented vegetables.
PubMed: 37107388
DOI: 10.3390/foods12081593 -
Current Research in Food Science 2023Wheat-gluten, the protein-rich portion of wheat, can be processed to produce a highly savory sauce product after solid and liquid-state fermentation (SSF and LSF) with...
Wheat-gluten, the protein-rich portion of wheat, can be processed to produce a highly savory sauce product after solid and liquid-state fermentation (SSF and LSF) with the inoculation of selected lactic acid bacteria (LAB) and yeast under salt-free condition. However, limited research has been done on the impact of different types of microbes in this process. This work studied the flavour impact on fermented wheat-gluten by the single inoculation of or one yeast ( or ). Glucose was depleted during LSF in all treatments. Lactic acid production increased over time in -fermented samples but not in yeast-fermented samples. Cysteine, serine and arginine remained low over LSF in -fermented samples but increased in yeast-fermented samples. More fruity esters such as isoamyl acetate and isobutyl acetate were detected in samples fermented by , while boosted the production of alcohols such as 3-methyl butanol and 2-phenylethyl alcohol. Principal component analysis revealed a clear difference in volatile profiles of the samples fermented with different strains. Therefore, the fermented sauce can potentially be processed into different flavor directions, and based on the flavor profile, be used in different food applications.
PubMed: 37033740
DOI: 10.1016/j.crfs.2023.100492 -
Moscow University Biological Sciences... 2022The taxonomic composition and spatial localization of yeast and bacteria in kefir grains (KG) obtained for study from different regions of the planet were investigated....
The taxonomic composition and spatial localization of yeast and bacteria in kefir grains (KG) obtained for study from different regions of the planet were investigated. The diversity of their microbiome has been demonstrated by high-throughput sequencing of bacterial 16S rRNA genes and the ITS1 region of the 18S-ITS1-5.8S-ITS2-28S complex of yeast rRNA. It has been established that the main representatives of the complex community of KG from different regions are lactic acid bacteria (LAB; lactobacilli, lactococci, and spp. in different ratios) and different types of yeast of the genus (family ). Acetic acid bacteria and a small percentage of yeast were detected in the KG from Tibet, and yeast was detected in the KG from Ossetia.
PubMed: 36843649
DOI: 10.3103/S0096392522040010 -
Foods (Basel, Switzerland) Oct 2022There is a lack of studies evaluating the metabolic contribution of non- yeasts in early fermentation phases. This study aimed to investigate the volatile aroma profiles...
There is a lack of studies evaluating the metabolic contribution of non- yeasts in early fermentation phases. This study aimed to investigate the volatile aroma profiles produced by various non- yeasts just before sequential inoculation with to provide an insight into the particular effects they induce at this stage. The grape must of Malvazija istarska was inoculated with monocultures of , , , , and , alongside a control. Eighty volatile compounds were quantified via headspace solid-phase microextraction and gas chromatography-mass spectrometry, and the data were statistically elaborated. Volatile profiles of non- yeasts differed significantly from the control. Most treatments caused increases in linalool and β-damascenone, decreases in higher alcohols and fatty acids, and improved synthesis of odoriferous esters. and produced compounds not commonly found in fermented wines. Multivariate statistical analysis linked the investigated yeasts to specific, particularly abundant compounds. Future studies should explore to what degree these contributions persist after sequential inoculation with in diverse grape must matrices.
PubMed: 36230163
DOI: 10.3390/foods11193088 -
Foods (Basel, Switzerland) Oct 2022Viticulture is one of the traditional industries in Slovakia, where there are six wine-growing regions: Malokarpatska, Southern Slovakia, Central Slovakia, Nitra,...
Viticulture is one of the traditional industries in Slovakia, where there are six wine-growing regions: Malokarpatska, Southern Slovakia, Central Slovakia, Nitra, Eastern Slovakia, and Tokaj. This study focuses on the detection of microbiota in soil samples, grape leaves and berries, and samples taken from fermenting must and young wine (the variety Tramín červený) in relation to the detected concentrations of biogenic amines during the fermentation process. In the examined samples, the number of yeasts and molds (from 3.8 to 6.8 log cfu/g or mL) and TVC (from 3.7 to 6.5 log cfu/g or mL) were determined via culture examination. At the same time, the number of LAB (from ˂3.0 to 4.4 log cfu/g or mL) was determined, which was the highest on day 4 of the must fermentation process and was related to the detected of the highest concentration of biogenic amines (histamine and tyramine) on day 6 in the investigated must samples using the UHPLC system. Mycobiota species were identified by MALDI-TOF MS, PCR, ITS-PCR-RFLP, and PCR sequencing of the amplified products. The study confirmed the presence of the yeasts . At the same time, the presence of molds ( and ) was also confirmed in soil samples, leaves, grape berries, and fresh grape must. The study confirmed the reduction in the species diversity of the microbiota during the must fermentation process, which resulted in decreases in the concentrations of the monitored biogenic amines in the early stages of the must fermentation process and young wine of the variety Tramín červený.
PubMed: 36230137
DOI: 10.3390/foods11193061 -
New Microbes and New Infections 2022
PubMed: 36177393
DOI: 10.1016/j.nmni.2022.101018 -
Food Research International (Ottawa,... Oct 2022This work aimed to evaluate the performance of co-cultivation of potential probiotic yeast and lactic acid bacteria (LAB) in producing plant-based fermented beverages....
This work aimed to evaluate the performance of co-cultivation of potential probiotic yeast and lactic acid bacteria (LAB) in producing plant-based fermented beverages. The co-culture comprised LAB Lactiplantibacillus plantarum CCMA0743 with the yeasts Pichia kluyveri CCMA 0615, Pichia guilliermondii CCMA 1753 and Debaryomyces hansenii CCMA 1761 separately. The plant substrate was 75 g oat, 175 g sunflower seeds, and 75 g almonds. The viability of microorganisms in the plant-based matrix was evaluated during fermentation, storage at 4 °C, and under simulated gastrointestinal tract (GIT) conditions. Chemical analysis, antioxidant activity, and sensory profile of the beverages were also determined. The three yeasts and the LAB showed counts greater than 6.0 log CFU/mL after fermentation, and the plant-based matrix protected the yeasts during simulated digestion. P. kluyveri and D. hansenii showed higher survival than P. guilliermondii and L. plantarum after exposure to simulated GIT conditions. The pH of the plant-based matrix reduced from approximately 7 to 3.8. Lactic acid was the main organic acid produced during fermentation. In addition, 113 volatile compounds were detected by gas chromatography-mass spectrometry (GC-MS), including alcohols, aldehydes, alkanes, alkenes, acids, ester, ether, ketones, phenol, and amides. The beverage sensory profile varied with the co-culture. The co-culture D. hansenii and L. plantarum showed higher antioxidant activity than the other co-culture tested, and the homogeneous texture attribute characterized the beverage produced with this combination. Results show the suitability of tested co-cultures to produce a plant-based fermented beverage and indicate more significant potential for D. hansenii and L. plantarum co-culture as a starter for its functionalization.
Topics: Antioxidants; Coculture Techniques; Fermented Beverages; Gas Chromatography-Mass Spectrometry; Lactobacillales; Probiotics; Saccharomyces cerevisiae
PubMed: 36076400
DOI: 10.1016/j.foodres.2022.111697