Development of A Low-Alcoholic Fermented Beverage Employing Cashew Apple Juice and Non-Conventional Yeasts

Valorization of Cashew Apple Waste into a Low-Alcohol, Healthy Drink Using a Co-Culture of Cyberlindnera rhodanensis DK and Lactobacillus pentosus A14-6

This study investigated the potential of microbial fermentative transforming processes in valorizing the cashew apple by-product into a low-alcohol, health-benefiting beverage. We particularly investigated the use of a non-Saccharomyces yeast, Cyberlindnera rhodanensis DK, as the main targeted microbe. At 30 °C without agitation, C. rhodanensis DK caused changes in key parameters during the fermentation of cashew apple juice (CAJ) in terms of varied pH values and initial sugar concentrations. This result indicated that pure CAJ, with pH adjusted to 6 and with the original 6.85% (w/v) total sugar content, was the most feasible condition, as glucose and fructose were mostly consumed at 12 days of fermentation. A co-culture approach with either Saccharomyces cerevisiae TISTR 5088 or Lactobacillus pentosus A14-6 was investigated to improve both physicochemical and fermentation characteristics. Co-fermentation with S. cerevisiae TISTR 5088 resulted in significantly increased ethanol accumulation to 33.61 ± 0.11 g/L, but diminished bioactive compounds, antioxidant activity, and antidiabetic potential. In contrast, co-fermentation with L. pentosus A14-6 demonstrated excellent outcomes, as it significantly increased sugar consumption and finally remained at only 4.95 g/L compared to C. rhodanensis DK alone, produced lower levels of ethanol at only 19.47 ± 0.06 g/L, and higher total titratable acid (TTA), resulting in a final pH of 3.6. In addition, co-fermentation with this lactic acid bacterium significantly enhanced bioactive compounds and antioxidant activity and also retained potential antidiabetic properties. These findings highlight the feasibility of using tailored microbial fermentation strategies to produce low-alcohol beverages with enhanced health-promoting properties from CAJ; however, product-development processes following health food regulations and sensory evaluation are necessary.

Exploring future applications of the apiculate yeast Hanseniaspora

As a metaphor, lemons get a bad rap; however the proverb 'if life gives you lemons, make lemonade' is often used in a motivational context. The same could be said of Hanseniaspora in winemaking. Despite its predominance in vineyards and grape must, this lemon-shaped yeast is underappreciated in terms of its contribution to the overall sensory profile of fine wine. Species belonging to this apiculate yeast are known for being common isolates not just on grape berries, but on many other fruits. They play a critical role in the early stages of a fermentation and can influence the quality of the final product. Their deliberate addition within mixed-culture fermentations shows promise in adding to the complexity of a wine and thus provide sensorial benefits. Hanseniaspora species are also key participants in the fermentations of a variety of other foodstuffs ranging from chocolate to apple cider. Outside of their role in fermentation, Hanseniaspora species have attractive biotechnological possibilities as revealed through studies on biocontrol potential, use as a whole-cell biocatalyst and important interactions with Drosophila flies. The growing amount of 'omics data on Hanseniaspora is revealing interesting features of the genus that sets it apart from the other Ascomycetes. This review collates the fields of research conducted on this apiculate yeast genus.

De novo assembly and characterization of the draft genome of the cashew (Anacardium occidentale L.)

Cashew is the second most important tree nut crop in the global market. Cashew is a diploid and heterozygous species closely related to the mango and pistachio. Its improvement by conventional breeding is slow due to the long juvenile phase. Despite the economic importance, very little genomics/transcriptomics information is available for cashew. In this study, the Oxford nanopore reads and Illumina reads were used for de novo assembly of the cashew genome. The hybrid assembly yielded a 356.6 Mb genome corresponding to 85% of the estimated genome size (419 Mb). The BUSCO analysis showed 91.8% of genome completeness. Transcriptome mapping showed 92.75% transcripts aligned with the assembled genome. Gene predictions resulted in the identification of 31,263 genes coding for a total of 35,000 gene isoforms. About 46% (165 Mb) of the cashew genome comprised of repetitive sequences. Phylogenetic analyses of the cashew with nine species showed that it was closely related to Mangifera indica. Analysis of cashew genome revealed 3104 putative R-genes. The first draft assembly of the genome, transcriptome and R gene information generated in this study would be the foundation for understanding the molecular basis of economic traits and genomics-assisted breeding in cashew.

A high‐throughput screening method for the discovery of Saccharomyces and non‐ Saccharomyces yeasts with potential in the brewing industry

Both Saccharomyces and non-Saccharomyces yeast strains are of great importance for the fermentation industry, especially with the flourishing of craft breweries, which are driving current innovations. Non-conventional yeasts can produce novel beverages with attractive characteristics such as flavour, texture, and reduced alcohol content; however, they have been poorly explored. A new method for screening the fitness of conventional and non-conventional yeast libraries utilising robotic platforms and solidified media representing industrial conditions is proposed. As proof of concept, a library formed of 6 conventional and 17 non-conventional yeast strains was distributed in 96, 384 and 1536 arrays onto a YPD agar medium. Following this, the library was replicated in different conditions mimicking beer and cider fermentation conditions. The colony size was monitored over time, and fitness values measured in maximum pixels/h and maximum biomass were calculated. Significant differences in growth were observed in between the different strains and conditions. As examples, Candida milleri Y-7245 displayed good performance in wort conditions, and Kazachstania yakushimaensis Y-48837 stood out for its performance in apple juice. The method is proposed to be used as a pre-screening step when studying vast yeast libraries. This would enable interested parties to discover potential hits for further study at a low initial cost. Furthermore, this method can be used in other applications where the desired screening media can be solidified.

Microbiological and Chemical Characteristics of Wet Coffee Fermentation Inoculated With Hansinaspora uvarum and Pichia kudriavzevii and Their Impact on Coffee Sensory Quality

Hansinaspora uvarum and Pichia kudriavzevii were used as starter cultures to conduct inoculated wet fermentations of coffee beans, and their growth, metabolic activities and impact on the flavor, aroma and overall sensory quality of coffee were compared with spontaneous fermentation (control). H. uvarum and P. kudriavzevii dominated the fermentations, growing to maximum populations of about 10.0 log CFU/ml compared with 8.0 log CFU/ml in the spontaneous fermentation. The dominance of the inoculated yeasts led to faster and more complete utilization of sugars in the mucilage, with resultant production of 2–3 fold higher concentrations of metabolites such as glycerol, alcohols, aldehydes, esters, and organic acids in the fermented green beans. Cup tests showed coffee produced from the inoculated fermentations, especially with P. kudriavzevii, received higher scores for flavor, aroma and acidity than the control. The findings of this study confirmed the crucial role of yeasts in the wet fermentation of coffee beans and their contribution to high quality coffee, and demonstrated the potential H. uvarum and P. kudriavzevii as starter cultures in the process.

Recent Trends in the Analysis of Chemical Contaminants in Beverages

Chemical contaminants should not be present in beverages for human consumption, but could eventually be ingested by consumers as they may appear naturally from the environment or be produced by anthropogenic sources. These contaminants could belong to many different chemical sources, including heavy metals, amines, bisphenols, phthalates, pesticides, perfluorinated compounds, inks, ethyl carbamate, and others. It is well known that these hazardous chemicals in beverages can represent a severe threat by the potential risk of generating diseases to humans if no strict quality control is applied during beverages processing. This review compiles the most updated knowledge of the presence of potential contaminants in various types of beverages (both alcoholic and non-alcoholic), as well as in their containers, to prevent undesired migration. Special attention is given to the extraction and pre-concentration techniques applied to these samples, as well as to the analytical techniques necessary for the determination of chemicals with a potential contaminant effect. Finally, an overview of the current legislation is carried out, as well as future trends of research in this field.

Aromatic Potential of Diverse Non-Conventional Yeast Species for Winemaking and Brewing

Traditionally, Saccharomyces species are those used to conduct industrial alcoholic fermentations. Recently, an increasing interest has arisen with respect to the potential of so-called non-conventional yeasts to improve wine and beer aroma profiles, keeping the particular terroir of each region or for the development of craft beers. In this study, the potential of diverse non-conventional yeasts to improve aroma in winemaking and brewing was investigated, testing several pure and mixed culture combinations. In addition, a comparison between microscale and labscale was carried out in order to assess the value of microwine and microbeer as screening tools. The results indicated that non-Saccharomyces yeasts were good candidates to enhance or diversify aroma profiles in alcoholic beverages, especially regarding acetate ester yield and fruity aromas. However, mixed cultures with Saccharomyces spp. are normally required to achieve a successful fermentation. The adjustment of pithing ratios is crucial for this purpose. Microscale is presented as an effective and efficient screening tool to compare different culture combinations, although scaling-up will always be necessary in order to get results closer to real winemaking or brewing processes.

Modern Technologies and Their Influence in Fermentation Quality

Since the beginning of enology and fermentation research, wine quality has been parametrized from a chemical and sensory point of view [...]