Growth Dynamics and Diversity of Yeasts during Spontaneous Plum Mash Fermentation of Different Varieties

The influence of fruit varieties on yeast ecology during spontaneous plum mash fermentation was investigated. Yeast colonies were isolated from mashes obtained from four plum varieties throughout fermentation in laboratory conditions during two consecutive years. The yeast strains were differentiated by random amplification of polymorphic DNA (RAPD-PCR) and identified by the 26S rDNA D1/D2 sequence analysis. Hanseniaspora uvarum, Metschnikowia spp. and Pichia kudriavzevii were the dominant yeasts during the early stages of plum mash fermentation, while the middle and end phases were dominated by Saccharomyces cerevisiae. The strains of Candida sake, Nakazawaea ernobii, Pichia kluyveri, Rhodotorula mucilaginosa and Wickerhamomyces anomalus were also detected in fermenting plum mashes. Metschnikowia sp. M1, H. uvarum H1 and H2 strains were detected in all samples, irrespective of the tested variety and year. Investigation of the impact of individual yeast strains on the production of volatile compounds showed the potential possibility of using them as starter cultures.

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Yeasts from Chinese strong flavour Daqu samples: isolation and evaluation of their potential for fortified Daqu production

AMB Express ◽

10.1186/s13568-021-01337-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Shunchang Pu ◽

Yu Zhang ◽

Ning Lu ◽

Cuie Shi ◽

Shoubao Yan

Keyword(s):

Volatile Compounds ◽

Rapd Analysis ◽

Kluyveromyces Lactis ◽

Inoculum Size ◽

Fermentation Efficiency ◽

Wickerhamomyces Anomalus ◽

Yeast Strains ◽

Saccharomyces Kudriavzevii ◽

Pichia Kluyveri ◽

The Impact

AbstractIn total, 16 yeast were isolated from Chinese strong flavour Daqu samples and underwent RAPD analysis and identification. Totally, 11 different species were identified among these isolates including Saccharomyces cerevisiae, Hanseniaspora vineae, Pichia kluyveri, Trichosporon asahii, Wickerhamomyces anomalus, Kluyveromyces lactis, Yarrowia lipolytica, Wickerhamomyces mori, Galactomyces geotrichum, Dabaryomyces hansenii, and Saccharomyces kudriavzevii. To understand the impact of these yeast strains on the quality and flavour of Daqu, we then assessed volatile compounds associated with Daqu samples fermented with corresponding strains. These analyses revealed strain YE006 exhibited the most robust ability to produce ethanol via fermentation but yielded relatively low quantities of volatile compounds, whereas strain YE010 exhibited relatively poor fermentation efficiency but produced the greatest quantity of volatile compounds. These two yeast strains were then utilized in a mixed culture to produce fortified Daqu, with the optimal inoculum size being assessed experimentally. These analyses revealed that maximal fermentation, saccharifying, liquefying, and esterifying power as well as high levels of volatile compounds were achieved when using a 2% inoculum composed of YE006/YE010 at a 1:2 (v/v) ratio. When the liquor prepared using this optimized fortified Daqu was compared to unfortified control Daqu, the former was found to exhibit significantly higher levels of flavour compounds and better sensory scores. Overall, our findings may provide a reliable approach to ensuring Daqu quality and improving the consistency and flavour of Chinese strong-flavour liquor through bioaugmentation.

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Diversity of Yeasts Involved in Cocoa Fermentation of Six Major Cocoa-Producing Regions in Ivory Coast

European Scientific Journal ESJ ◽

10.19044/esj.2017.v13n30p496 ◽

2017 ◽

Vol 13 (30) ◽

pp. 496 ◽

Cited By ~ 2

Author(s):

Odilon Koff ◽

Lamine Samagaci ◽

Bernadette Goualie ◽

Sebastien Niamke

Keyword(s):

Ivory Coast ◽

Growth Dynamics ◽

Rflp Analysis ◽

Starter Cultures ◽

Raw Material ◽

Intraspecific Diversity ◽

Cocoa Bean ◽

Pichia Kudriavzevii ◽

Cocoa Bean Fermentation ◽

Cocoa Fermentation

Cocoa beans (Theobroma cacao L.) are the raw material for chocolate production. Fermentation of cocoa pulp is crucial for developing chocolate flavor precursors. This fermentation is led by a succession of complex microbial communities where yeasts play key roles during the first stages of the process. In this study, we identified and analyzed the growth dynamics of yeasts involved in cocoa bean fermentation of six major cocoaproducing regions in Ivory Coast. A total of 743 yeasts were isolated, and were identified by sequencing of D1/D2 regions of 26S rDNA gene. These isolates included 11 species with a predominance of Pichia kudriavzevii (44,81 %), Pichia kluyveri (20,99 %) and Saccharomyces cerevisiae (18,97 %) respectively. In addition, the length polymorphism of the genetic marker ITS1-5.8S-ITS2 and PCR-RFLP analysis revealed an intraspecific diversity within the three-main species involved in cocoa fermentation of six major local regions in Ivory Coast. This intraspecific diversity could be exploited for selecting appropriate starter cultures.

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How Different Fermentation Type Affects Volatile Composition of Plum Jerkums

Applied Sciences ◽

10.3390/app11104658 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4658

Author(s):

Magdalena Januszek ◽

Paweł Satora

Keyword(s):

Volatile Compounds ◽

Current Paper ◽

Higher Alcohols ◽

High Quality ◽

Volatile Composition ◽

Spontaneous Fermentation ◽

Fermentation Efficiency ◽

Yeast Strains ◽

The Impact

Quality of plum jerkum is significantly associated to the profile of volatile compounds. Therefore, we decided to assess the impact of various fermentation types on selected properties of plum jerkums, especially compounds which contribute to the aroma of the finished product. We used the following yeast strains: S. cerevisiae S1, H. uvarum H2, and Ethanol RED (S. cerevisiae). Moreover, we considered spontaneous fermentation. S. cerevisiae and H. uvarum strains were isolated during the fermentation of Čačanska Lepotica or Węgierka Dąbrowicka (plum cultivars), respectively. As for fermentation type, spontaneous fermentation of H. uvarum H2 provided the best results. It could be associated to the fact that plum juices fermented with H. uvarum H2 presented the highest concentration of terpenoids, esters, or some higher alcohols. In the current paper, application of indigenous strains of yeasts resulted in the required oenological characteristics, e.g., highest fermentation efficiency and concentration of ethanol was determined in juices fermented with Ethanol RED (S. cerevisiae) and also with S. cerevisiae S1. Our results suggested that indigenous strains of yeasts present in plums demonstrate great potential for the production of plum jerkums of high quality.

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Isolation and Characterization of Yeasts from Rumen Fluids for Potential Use as Additives in Ruminant Feeding

Veterinary Sciences ◽

10.3390/vetsci8030052 ◽

2021 ◽

Vol 8 (3) ◽

pp. 52

Author(s):

Chanon Suntara ◽

Anusorn Cherdthong ◽

Metha Wanapat ◽

Suthipong Uriyapongson ◽

Vichai Leelavatcharamas ◽

...

Keyword(s):

Incubation Time ◽

Cellulase Activity ◽

The Other ◽

Pichia Kudriavzevii ◽

Factor B ◽

Yeast Strains ◽

Randomized Design ◽

Holstein Friesian ◽

The Media ◽

Completely Randomized Design

Saccharomyces cerevisiae is a yeast strain often used to improve the feed quality of ruminants. However, S. cerevisiae has limited capacity to provide biomass when inoculated with carbon sources and a low ability to produce cellulase enzymes. Here, we hypothesized that yeast in the rumen produces a large amount of biomass and could release cellulase enzymes to break down fiber content. Therefore, the aim of this study was to screen, isolate and identify yeast from the rumen fluids of Holstein Friesian steers and measure the efficiency of biomass production and cellulase activity. A fermentation medium containing sugarcane molasses as a carbon source and urea as a nitrogen source was optimized. Two fistulated–crossbred Holstein Friesian steers averaging 350 ± 20 kg body weight were used to screen and isolate the ruminal yeast. Two experiments were designed: First, a 12 × 3 × 3 factorial was used in a completely randomized design to determine biomass and carboxymethyl cellulase activity. Factor A was the isolated yeast and S. cerevisiae. Factor B was sugarcane molasses (M) concentration. Factor C was urea (U) concentration. In the second experiment, potential yeasts were selected, identified, and analyzed for 7 × 4 factorial use in a completely randomized design. Factor A was the incubation times. Factor B was the isolated yeast strains, including codes H-Khon Kaen University (KKU) 20 (as P. kudriavzevii-KKU20), I-KKU20 (C. tropicalis-KKU20), and C-KKU20 (as Galactomyces sp.-KKU20). Isolation was imposed under aerobic conditions, resulting in a total of 11 different colonies. Two appearances of colonies including asymmetric colonies of isolated yeast (indicated as A, B, C, E, and J) and ovoid colonies (coded as D, F, G, H, I, and K) were noted. Isolated yeast from the rumen capable of providing a high amount of biomass when inoculant consisted of the molasses 15% + urea 3% (M15 + U3), molasses 25% + urea 1% (M25 + U1), molasses 25% + urea 3% (M25 + U3), and molasses 25% + urea 5% (M25 + U5) when compared to the other media solution (p < 0.01). In addition, 11 isolated biomass-producing yeasts were found in the media solution of M25 + U1. There were 4 isolates cellulase producing yeasts discovered in the media solution of M25 + U1 and M25 + U5 whereas molasses 5% + urea 1% (M5 + U1), molasses 5% + urea 3% (M5 + U3), molasses 5% + urea 5% (M5 + U5), molasses 15% + urea 1% (M15 + U1), molasses 15% + urea 3% (M5 + U3), and M25 + U3 were found with 2, 3, 1, 2, 1, and 2 isolates, respectively. Ruminal yeast strains H-KKU20, I-KKU20, and C-KKU20 were selected for their ability to produce biomass. Identification of isolates H-KKU20 and I-KKU20 revealed that those isolates belonged to Pichia kudriavzevii-KKU20 and Candida tropicalis-KKU20 while C-KKU20 was identified as Galactomyces sp.-KKU20. Two strains provided maximum cell growth: P. kudriavzevii-KKU20 (9.78 and 10.02 Log cell/mL) and C. tropicalis-KKU20 (9.53 and 9.6 Log cells/mL) at 60 and 72 h of incubation time, respectively. The highest ethanol production was observed in S. cerevisiae at 76.4, 77.8, 78.5, and 78.6 g/L at 36, 48, 60, and 72 h of incubation time, respectively (p < 0.01). The P. kudriavzevii-KKU20 yielded the least reducing sugar at about 30.6 and 29.8 g/L at 60 and 72 h of incubation time, respectively. The screening and isolation of yeasts from rumen fluids resulted in 11 different yeasts being obtained. The potential yeasts discovered in the rumen fluid of cattle were Pichia kudriavzevii-KKU20, Candida tropicalis-KKU20, and Galactomyces sp.-KKU20. P. kudriavzevii-KKU20 had higher results than the other yeasts in terms of biomass production, cellulase enzyme activity, and cell number.

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Profile of Volatile Compounds of On-Farm Fermented and Dried Cocoa Beans Inoculated with Saccharomyces cerevisiae KY794742 and Pichia kudriavzevii KY794725

Molecules ◽

10.3390/molecules26020344 ◽

2021 ◽

Vol 26 (2) ◽

pp. 344

Author(s):

Gilson Celso Albuquerque Chagas Junior ◽

Nelson Rosa Ferreira ◽

Eloisa Helena de Aguiar Andrade ◽

Lidiane Diniz do Nascimento ◽

Francilia Campos de Siqueira ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Volatile Compounds ◽

Multivariate Analyses ◽

High Capacity ◽

Starter Cultures ◽

Cocoa Beans ◽

Pichia Kudriavzevii ◽

Fermentative Capacity ◽

Product Identity ◽

On Farm

This study aimed to identify the volatile compounds in the fermented and dried cocoa beans conducted with three distinct inoculants of yeast species due to their high fermentative capacity: Saccharomyces cerevisiae, Pichia kudriavzevii, the mixture in equal proportions 1:1 of both species, and a control fermentation (with no inoculum application). Three starter cultures of yeasts, previously isolated and identified in cocoa fermentation in the municipality of Tomé-Açu, Pará state, Brazil. The seeds with pulp were removed manually and placed in wooden boxes for the fermentation process that lasted from 6 to 7 days. On the last day of fermentation, the almonds were packaged properly and placed to dry (36 °C), followed by preparation for the analysis of volatile compounds by GC-MS technique. In addition to the control fermentation, a high capacity for the formation of desirable compounds in chocolate by the inoculants with P. kudriavzevii was observed, which was confirmed through multivariate analyses, classifying these almonds with the highest content of aldehydes, esters, ketones and alcohols and low concentration of off-flavours. We conclude that the addition of mixed culture starter can be an excellent alternative for cocoa producers, suggesting obtaining cocoa beans with desirable characteristics for chocolate production, as well as creating a product identity for the producing region.

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Influence of L. thermotolerans and S. cerevisiae Commercial Yeast Sequential Inoculation on Aroma Composition of Red Wines (Cv Trnjak, Babic, Blatina and Frankovka)

Fermentation ◽

10.3390/fermentation7010004 ◽

2020 ◽

Vol 7 (1) ◽

pp. 4

Author(s):

Ana-Marija Jagatić Korenika ◽

Ivana Tomaz ◽

Darko Preiner ◽

Marina Lavrić ◽

Branimir Šimić ◽

...

Keyword(s):

Yeast Strain ◽

Isoamyl Alcohol ◽

Starter Cultures ◽

Geranyl Acetate ◽

Red Wines ◽

Wine Quality ◽

Volatile Phenol ◽

Sequential Inoculation ◽

Commercial Yeast ◽

The Impact

Even though Saccharomyces cerevisiae starter cultures are still largely used nowadays, the non-Saccharomyces contribution is re-evaluated, showing positive enological characteristics. Among them, Lachancea thermotolerans is one of the key yeast species that are desired for their contribution to wine sensory characteristics. The main goal of this work was to explore the impact of L. thermotolerans commercial yeast strain used in sequential inoculation with S. cerevisiae commercial yeast on the main enological parameters and volatile aroma profile of Trnjak, Babić, Blatina, and Frankovka red wines and compare it with wines produced by the use of S. cerevisiae commercial yeast strain. In all sequential fermented wines, lactic acid concentrations were significantly higher, ranging from 0.20 mg/L in Trnjak up to 0.92 mg/L in Frankovka wines, while reducing alcohol levels from 0.1% v/v in Trnjak up to 0.9% v/v in Frankovka wines. Among volatile compounds, a significant increase of ethyl lactate and isobutyl acetate, geraniol, and geranyl acetate was detected in all wines made by use of L. thermotolerans. In Babić wines, the strongest influence of sequential fermentation was connected with higher total terpenes and total ester concentrations, while Trnjak sequentially fermented wines stood up with higher total aldehyde, volatile phenol, and total lactone concentrations. Control wines, regardless of variety, stood up with higher concentrations of total higher alcohols, especially isoamyl alcohol. The present work contributed to a better understanding of the fermentation possibilities of selected non-Saccharomyces strains in the overall red wine quality modeling.

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Processes, Challenges and Optimisation of Rum Production from Molasses—A Contemporary Review

Fermentation ◽

10.3390/fermentation7010021 ◽

2021 ◽

Vol 7 (1) ◽

pp. 21

Author(s):

Tinashe Mangwanda ◽

Joel B. Johnson ◽

Janice S. Mani ◽

Steve Jackson ◽

Shaneel Chandra ◽

...

Keyword(s):

Management Practices ◽

Scientific Literature ◽

Asia Pacific ◽

Yeast Strains ◽

Challenges And Opportunities ◽

The Caribbean ◽

The Impact ◽

Production Industry ◽

Stringent Quality

The rum industry is currently worth USD 16 billion, with production concentrated in tropical countries of the Caribbean and Asia-Pacific regions. The primary feedstock for rum production is sugar cane molasses, a by-product of sugar refineries. The main variables known to affect rum quality include the composition of the molasses, the length of fermentation, and the type of barrels and length of time used for aging the rum. The goal of this review is to provide an overview of the impact of these variables on rum quality, and to highlight current challenges and opportunities in the production of rum from molasses. In order to achieve this, we review the relevant contemporary scientific literature on these topics. The major contemporary challenges in the rum production industry include minimising the effects of variability in feedstock quality, ensuring the fermentation process runs to completion, preventing microbial contamination, and the selection and maintenance of yeast strains providing optimum ethanol production. Stringent quality management practices are required to ensure consistency in the quality and organoleptic properties of the rum from batch to batch. Further research is required to fully understand the influences of many of these variables on the final quality of the rum produced.

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High Potential of Pichia kluyveri and Other Pichia Species in Wine Technology

International Journal of Molecular Sciences ◽

10.3390/ijms22031196 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1196

Author(s):

Javier Vicente ◽

Fernando Calderón ◽

Antonio Santos ◽

Domingo Marquina ◽

Santiago Benito

Keyword(s):

Ethanol Yield ◽

Color Stability ◽

Quality Parameters ◽

Wine Industry ◽

Wine Aroma ◽

Wine Quality ◽

Promising Tool ◽

Pichia Kluyveri ◽

The Impact ◽

Fermentative Yeast

The surfaces of grapes are covered by different yeast species that are important in the first stages of the fermentation process. In recent years, non-Saccharomyces yeasts such as Torulaspora delbrueckii, Lachancea thermotolerans, Metschnikowia pulcherrima, and Pichia kluyveri have become popular with regard to winemaking and improved wine quality. For that reason, several manufacturers started to offer commercially available strains of these non-Saccharomyces species. P. kluyveri stands out, mainly due to its contribution to wine aroma, glycerol, ethanol yield, and killer factor. The metabolism of the yeast allows it to increase volatile molecules such as esters and varietal thiols (aroma-active compounds), which increase the quality of specific varietal wines or neutral ones. It is considered a low- or non-fermentative yeast, so subsequent inoculation of a more fermentative yeast such as Saccharomyces cerevisiae is indispensable to achieve a proper fermented alcohol. The impact of P. kluyveri is not limited to the grape wine industry; it has also been successfully employed in beer, cider, durian, and tequila fermentation, among others, acting as a promising tool in those fermentation processes. Although no Pichia species other than P. kluyveri is available in the regular market, several recent scientific studies show interesting improvements in some wine quality parameters such as aroma, polysaccharides, acid management, and color stability. This could motivate yeast manufacturers to develop products based on those species in the near future.

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China’s Belt and Road Initiative: Will it Make or Mar Development in the Central and West Africa Subregions?

Journal of Public Administration and Governance ◽

10.5296/jpag.v10i4.17876 ◽

2020 ◽

Vol 10 (4) ◽

pp. 19

Author(s):

William G. Dzekashu ◽

Julius N. Anyu

Keyword(s):

Growth Dynamics ◽

Sustainable Growth ◽

Agricultural Products ◽

Belt And Road Initiative ◽

The West ◽

Colonial Era ◽

Post Colonial ◽

Belt And Road ◽

The Impact ◽

Domestic Products

The West, chiefly Europe, left political footmarks in Africa from the Colonial Era, along with varying economic footprints and surviving engagements in the immediate Post-colonial Era. However, the relationships between Africa and her former colonial masters have hardly yielded much to the former following the wave of independence, leading to the perception of failed relationships. This perception of failure to deliver on their undertakings has left Africa with only one option—China. The latter has been addressing some of Africa’s urgent infrastructure needs in return for natural resources and agricultural products. These engagements on the surface appear to be good business, but on further examination seem questionable notably as it relates to debt distress on vulnerable economies. To increase her footprint within the continent, China extended her Belt and Road Initiative (BRI) to most African nations who have signed a memorandum of understanding for future development projects. Though the commitments usually are unspecified, China’s investments have seen rapid growth since the early 2000s, largely owing to the implementation of the BRI. The memoranda have had the potential to strengthen ties with partner nations. The expansion to include Africa in its economic participation in the BRI has left the West questioning China’s motives while reinforcing suspicions about possible future US-China conflict. The impact of BRI on the African continent is quite visible in all the subregions, especially in their improved gross domestic products. A burning question has been whether these partnerships represent win-win relationships for sustainable growth or debt-growth dynamics.

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The impact of the partial replacement of sodium chloride in the development of starter cultures during Italian salami production

BRAZILIAN JOURNAL OF FOOD TECHNOLOGY ◽

10.1590/1981-6723.03615 ◽

2018 ◽

Vol 21 (0) ◽

Cited By ~ 2

Author(s):

Claudia Fieira ◽

João Francisco Marchi ◽

Daiana Marafão ◽

Alexandre da Trindade Alfaro

Keyword(s):

Sodium Chloride ◽

Starter Culture ◽

Microbiological Quality ◽

Sodium Content ◽

Starter Cultures ◽

Partial Replacement ◽

High Sodium ◽

Cured Meat ◽

The Impact

Abstract Italian salami is a cured meat with high sodium contents which is easy, fast and convenient to consume. Starter cultures are used to improve its sensory characteristics and refine its technological manufacturing process. The goal of this study was to reduce the sodium content in Italian salami through the partial replacement of sodium chloride by potassium chloride, magnesium chloride and calcium chloride, and evaluate the viability of the Lactobacillus sp. and Staphylococcus sp. cells found in the starter culture. Four formulations were elaborated: one with, and one without the starter culture, but both with the addition of sodium chloride; and two with the partial replacement of 60% of the sodium chloride: the first with KCl, and the other with a mixture of KCl, MgCl2 and CaCl2. Physicochemical and microbiological evaluations were carried out to monitor the ripening and the quality of the final product. The partial replacement of NaCl by other salts (MgCl2, CaCl2, KCl) did not interfere in the growth of the starter culture in the Italian salami, neither did it affect the majority of the physicochemical parameters of the Italian salami nor the microbiological quality of the final product.

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