Microbiological and chemical characteristics of tarubá, an indigenous beverage produced from solid cassava fermentation

A catalog of ethanol-producing microbes in humans

Aim: Endogenous ethanol production emerges as a mechanism of nonalcoholic steatohepatitis, obesity, diabetes and auto-brewery syndrome. Methods: To identify ethanol-producing microbes in humans, we used the NCBI taxonomy browser and the PubMed database with an automatic query and manual verification. Results: 85 ethanol-producing microbes in human were identified. Saccharomyces cerevisiae, Candida and Pichia were the most represented fungi. Enterobacteriaceae was the most represented bacterial family with mainly Escherichia coli and Klebsiella pneumoniae. Species of the Lachnospiraceae and Clostridiaceae family, of the Lactobacillales order and of the Bifidobacterium genus were also identified. Conclusion: This catalog will help the study of ethanol-producing microbes in human in the pathophysiology, diagnosis, prevention and management of human diseases associated with endogenous ethanol production.

Amazonian fermentations: an analysis of industrial and social technology as tools for the development of bioeconomy in the region

This review article explores the potential of fermentations in the Amazon region as catalysts for economic and social development. It highlights the rich cultural and gastronomic diversity of the Amazon, focusing on indigenous fermented products. Two main products, tucupi and caxiri, are discussed in detail, emphasizing their significance in local cuisine and culture. The review examines the challenges and opportunities for industrial applications of these products, as well as their potential for social technology initiatives, particularly in the context of family farming. The sustainable production of native fermented products in the Amazon is seen as a means to preserve biodiversity, empower local communities, and promote cultural heritage. The article concludes that both industrial and social technologies have complementary roles in promoting economic growth, cultural preservation, and the well-being of the Amazon region, making it a promising hub for innovative and sustainable fermented food products on a global scale.

"Masato de Yuca" and "Chicha de Siete Semillas" Two Traditional Vegetable Fermented Beverages from Peru as Source for the Isolation of Potential Probiotic Bacteria

In this work, two Peruvian beverages "Masato de Yuca," typical of the Amazonian communities made from cassava (Manihot esculenta), and "Chicha de Siete Semillas," made from different cereal, pseudo-cereal, and legume flours, were explored for the isolation of lactic acid bacteria after obtaining the permission of local authorities following Nagoya protocol. From an initial number of 33 isolates, 16 strains with different RAPD- and REP-PCR genetic profiles were obtained. In Chicha, all strains were Lactiplantibacillus plantarum (formerly Lactobacillus plantarum), whereas in Masato, in addition to this species, Limosilactobacillus fermentum (formerly Lactobacillus fermentum), Pediococcus acidilactici, and Weissella confusa were also identified. Correlation analysis carried out with their carbohydrate fermentation patterns and enzymatic profiles allowed a clustering of the lactobacilli separated from the other genera. Finally, the 16 strains were submitted to a static in vitro digestion (INFOGEST model) that simulated the gastrointestinal transit. Besides, their ability to adhere to the human epithelial intestinal cell line HT29 was also determined. Following both procedures, the best probiotic candidate was Lac. plantarum Ch13, a robust strain able to better face the challenging conditions of the gastrointestinal tract and showing higher adhesion ability to the intestinal epithelium in comparison with the commercial probiotic strain 299v. In order to characterize its benefit for human health, this Ch13 strain will be deeply studied in further works.

Microorganisms present in artisanal fermented food from South America

Artisanal fermented products (foods and beverages) are produced in an artisanal way in many countries around the world. The main purpose of fermentation is to preserve the food, improve its safety, increase the nutritional and health-promoting value and add specific flavours. In South America, there is a great variety of fermented food produced in an artisanal way. Different raw materials are used such as potatoes, sweet potato, cassava, maize, rice, milk (cow, ewe, goat) and meat (beef, goat, lamb, llama and guanaco). Some of these fermented foods are typical of the region and are part of the culture of native communities, e.g. tocosh, masa agria, puba flour, charqui, chicha, champu and cauim among others (indigenous foods). However, other fermented foods produced in South America introduced by mainly European immigration, such as cheeses and dry sausages, and they are also produced in many different parts of the world. In this work, the microbial composition of the different artisanal fermented products produced in South America is reviewed, taking into consideration the associated raw materials, fermentation conditions and methodologies used for their production.

Lactic Acid Bacteria and Bioactive Amines Identified during Manipueira Fermentation for Tucupi Production

There is scarce information regarding lactic acid bacteria (LAB) and the production of biogenic amines during manipueira fermentation for tucupi. Thus, the objective of this study was to isolate and identify LAB, and to determine their impact on bioactive amine formation. Spontaneous fermentation of manipueira was carried out at laboratory scale and selected LAB colonies were isolated and identified by sequencing techniques and comparison with sequences from a virtual database. Only two LAB species of the genus Lactobacillus were identified during fermentation: Lactobacillus fermentum and Lactobacillus plantarum. L. fermentum was the predominant, whereas L. plantarum was only detected in manipueira prior to fermentation. Spermidine and putrescine were detected throughout fermentation, whereas histamine was produced at the final stage. There was positive correlation between LAB counts and putrescine and histamine levels, suggesting that the identified LAB are responsible for the synthesis of these amines during manipueira fermentation. Genetic assays are needed to verify whether the LAB identified have the genes responsible for decarboxylation of amino acids.

Effects of vacuum packaging storage of minimally processed cassava roots at various temperatures on microflora, tissue structure, starch extraction by wet milling and granule quality

BACKGROUND

Vacuum package storage is commonly applied to reduce postharvest deterioration in minimally processed cassava roots. However, the influence of vacuum packaging conditions on root end-use quality is poorly understood. Hence, the effects of vacuum packaged storage at ambient, refrigerated and freezing temperatures on microflora, cassava tissue structure and starch extraction by wet milling were studied.

RESULTS

Vacuum packaged storage temperature strongly affected cassava root quality. Minimal adverse effects were obtained with frozen storage. With refrigerated storage, there was negligible microbial growth but some disruption of the parenchyma cell wall structure suggestive of chilling injury. With ambient temperature storage, there was considerable Lactobacilli dominated fermentation. This caused substantial cell degradation, probably due to the production of extracellular cellulolytic and other cell wall degrading enzymes. A benefit of this cell wall breakdown was that it substantially improved starch extraction with wet milling from the stored cassava pieces; by 18% with pieces that had been ambient vacuum packaged and wet milled using a 2000 μm opening screen. However, ambient temperature storage resulted in some starch granule pitting due to the action of extracellular amylases from the fermenting microorganisms.

CONCLUSION

The best vacuum packaging storage conditions for minimally processed cassava depends on application and cost. For short-term storage, refrigeration would be best for vegetable-type products. For several months storage, freezing is best. For wet milling applications, this could be combined with subsequent short-term ambient temperature storage as it improves starch extraction efficiency and could reduce distribution energy costs. © 2021 Society of Chemical Industry.

Isolation, Identification, and Screening of Lactic Acid Bacteria with Probiotic Potential in Silage of Different Species of Forage Plants, Cocoa Beans, and Artisanal Salami

The objective of this study was to isolate and characterize lactic acid bacteria with probiotic potential in silages of different species of forage plants, cocoa beans, and artisanal salami. The obtained isolates were submitted to the following evaluations: (i) screening for tolerance to pH 2 and bile salts, (ii) genotypic identification of isolates, (iii) survival in simulated gastric and pancreatic conditions, (iv) antimicrobial activity, (v) antibiotic susceptibility and safety, and (vi) properties associated with adhesion capacity. A total of 82 isolates were obtained and were screened for pH 2.0 tolerance and capacity to growth in the presence of bile salts (1.0 and 2.0%). Only 19 strains simultaneously presented tolerance to pH 2.0 and bile salts. These 19 strains were evaluated for genetic profile by Box-PCR. Subsequently, the selected strains were subjected to partial sequencing of the 16S rRNA gene. The species Lactobacillus plantarum was prevalent. The identified strains were evaluated for survival under simulated gastric and pancreatic conditions. Some strains have shown tolerance in both conditions. Different strains showed variations in antimicrobial activity, susceptibility to antibiotics, and properties associated with adhesion (hydrophobicity, autoaggregation, coaggregation, and adhesion to CaCo2 cells). All strains were negative for hemolysis, DNase, gelatinase, and biogenic amine synthesis activity. The L. plantarum SBR64.7 strain can be considered the most promising for it presented the lowest viability reduction when exposed to gastric and pancreatic juices.

Fermentative Microbes of Khadi, a Traditional Alcoholic Beverage of Botswana

Khadi is a popular traditional alcoholic beverage in rural households in Botswana. The product is produced by fermentation of ripened sun-dried Grewia flava (Malvaceae) fruits supplemented with brown table sugar. Despite its popularity, its growing consumer acceptance, its potential nutritional value, and its contribution to the socio-economic lifestyle of Botswana, the production process remains non-standardized. Non-standardized production processes lead to discrepancies in product quality and safety as well as varying shelf life. Identification of unknown fermentative microorganisms of khadi is an important step towards standardization of its brewing process for entrance into commercial markets. The aim of this study was to isolate and identify bacteria and yeasts responsible for fermentation of khadi. Yeasts and bacteria harbored in 18 khadi samples from 18 brewers in central and northern Botswana were investigated using classic culture-dependent techniques and DNA sequencing methods. Additionally, we used the same techniques to investigate the presence of bacteria and yeasts on six batches of ripened-dried G. flava fruits used for production of the sampled brews. Our results revealed that Saccharomyces cerevisiae closely related to a commercial baker’s yeast strain sold locally was the most predominant yeast species in khadi suggesting a possible non-spontaneous brewing process. However, we also detected diverse non-Saccharomyces yeasts, which are not available commercially in retail shops in Botswana. This suggests that spontaneous fermentation is partially responsible for fermentation of khadi. This study, presenting the first microbiological characterization of a prominent traditional alcoholic beverage in Botswana, is vital for development of starter cultures for the production of a consistent product towards the commercialization of khadi.

Effect of Short Fermentation Times with Lactobacillus paracasei in Rheological, Physical and Chemical Composition Parameters in Cassava Dough and Biscuits

Dough fermentation with lactic acid bacteria has been extensively studied due to the associated health benefits and its effects on physical and rheology parameters in dough and bread. However, most of the studies rely on long fermentation times. The aim of this study is to evaluate the effect of short fermentation times (0 to 8 h) with Lactobacillus paracasei in rheology, physical and chemical properties on cassava dough and biscuits. Both storage modulus and loss modulus decreased as the fermentation times increased, down to 54,206.67 ± 13,348 and 17,453.89 ± 3691 Pa, respectively. Fermentation with L. paracasei influenced biscuit’s hardness and chemical properties, and gas cell sizes were increased notably. These results suggest that short fermentation times could be used to improve dough’s rheological characteristics.

Antagonistic lactic acid bacteria in association with Saccharomyces cerevisiae as starter cultures for standardization of sour cassava starch production

In order to improve cassava's palatability and reduce its toxicity, this root is fermented and applied in foods, such as sour cassava starch used to prepare cheese bread and biscuits. This fermentation occurs spontaneously with lactic acid bacteria (LAB) and yeasts. However, it remains an empirical process, with long duration and lack of product quality homogeneity. This work aims to use starter cultures in a pilot-scale fermentation process for the production of sour cassava starch. After differentiation of strains, Lactobacillus plantarum Lp3, which exhibited great total titratable acidity (TTA) (5.01 ± 0.05%) and antagonistic activity against Bacillus cereus, Escherichia coli and Salmonella Typhimurium, together with Lactobacillus brevis Lb9 (with lesser TTA values: 2.71 ± 0.10%, but amylolytic activity: 2.75 ± 0.61 mm) were tested as single and co-cultures with Saccharomyces cerevisiae UFMG-A1007. LAB and yeasts were inoculated at counts of 8 and 7 log₁₀ CFU/g, respectively, and they remained until the 28th day only in co-culture, highlighting the importance of the yeast for the LAB viability. Although single cultures lead to higher acidity during fermentation, the final product acidity obtained with single cultures did not differ from the acidity obtained with L. plantarum Lp3 in association with S. cerevisiae UFMG-A1007. Therefore, this co-culture exhibited higher potential to be tested as a starter culture in industrial-scale fermentation studies because both microorganisms were in high counts until the end of fermentation and contributed to a final product safe for human consumption, with satisfactory acidity, expansion capacity, and physicochemical properties.

Microbial Ecology of Fermented Vegetables and Non-Alcoholic Drinks and Current Knowledge on Their Impact on Human Health

Fermented foods are currently experiencing a re-discovery, largely driven by numerous health benefits claims. While fermented dairy, beer, and wine (and other alcoholic fermented beverages) have been the subject of intensive research, other plant-based fermented foods that are in some case widely consumed (kimchi/sauerkraut, pickles, kombucha) have received less scientific attention. In this chapter, the current knowledge on the microbiology and potential health benefits of such plant-based fermented foods are presented. Kimchi is the most studied, characterized by primarily acidic fermentation by lactic acid bacteria. Anti-obesity and anti-hypertension properties have been reported for kimchi and other pickled vegetables. Kombucha is the most popular non-alcoholic fermented drink. Kombucha's microbiology is remarkable as it involves all fermenters described in known fermented foods: lactic acid bacteria, acetic acid bacteria, fungi, and yeasts. While kombucha is often hyped as a "super-food," only antioxidant and antimicrobial properties toward foodborne pathogens are well established; and it is unknown if these properties incur beneficial impact, even in vitro or in animal models. The mode of action that has been studied and demonstrated the most is the probiotic one. However, it can be expected that fermentation metabolites may be prebiotic, or influence host health directly. To conclude, plant-based fermented foods and drinks are usually safe products; few negative reports can be found, but more research, especially human dietary intervention studies, are warranted to substantiate any health claim.

Yeasts and bacteria associated with kocho, an Ethiopian fermented food produced from enset (Ensete ventricosum)

Enset (Ensete ventricosum) is the basis of the staple food consumed by about 20% of the Ethiopian population. Kocho is one of the food products generated from enset by spontaneous fermentation of decorticated and pulverized pseudostem and corm sections. We isolated culturable microbes associated with kocho from different stages of fermentation. Twelve yeast species, six lactic acid bacteria (LABs) species and eleven species of aerobic bacteria were identified by sequencing ITS/D1D2 regions of 26S rDNA of yeasts and 16S rDNA of bacteria, respectively. More yeast species were identified in fresh (fermented for 2–5 days) kocho, compared to long-term (7–12 months) fermented kocho, while we observed an opposite trend for LABs. In fresh kocho, the most frequently isolated yeast species were Pichia exigua, Galactomyces geotrichum, and Pichia fermentans. From mid-term (3–4 months) kocho most frequently Candida cabralensis, G. geotrichum, and Candida ethanolica were isolated. In the long-term fermentations, the most frequently isolated yeast was Saturnispora silva. Lactobacillus plantarum was the most frequently isolated LAB in both fresh and mid-term kocho. In long-term fermented kocho, Acetobacter pasteurianus and L. plantarum were most frequently isolated. L. plantarum was consistently isolated from all the three stages of fermentation. Aerobic bacteria in fresh kocho were mostly gram-negative, with Raoultella planticola and Pantoea agglomerans being the most frequently isolated species. In long-term fermented kocho, mainly gram-positive, spore-forming bacteria of the genus Bacillus were found, among them also species of the Bacillus cereus group, Bacillus anthracis and Bacillus thurigiensis.

Lactic Acid Bacteria from Andean Grain Amaranth: A Source of Vitamins and Functional Value Enzymes

Amaranth is a rediscovered pseudocereal with high nutritional properties. Lactic acid fermentation can increase the functional and nutritional value of foods. The aims of this study were to isolate and evaluate the functionality of lactic acid bacteria (LAB) from amaranth. LAB strains (<i>n</i> = 29) isolated from amaranth sourdough and grains included <i>Lactobacillus</i> (<i>L.</i>) <i>plantarum</i> (<i>n</i> = 8), <i>L. rhamnosus</i> (<i>n</i> = 6), <i>Enterococcus</i> (<i>E.</i>) <i>mundtii</i> (<i>n</i> = 4), <i>E. hermanniensis</i> (<i>n</i> = 3), <i>E. durans</i> (<i>n</i> = 1), <i>Enterococcus</i> sp. (<i>n</i> = 1), <i>Leuconostoc</i> (<i>Lc.</i>) <i>mesenteroides</i> (<i>n</i> = 3), and <i>Lc. mesenteroides </i>subsp<i>. mesenteroides </i>(<i>n</i> = 3). Only 21% of the strains showed the ability to synthesize capsular exopolysaccharides or display ropiness and only 8 strains showed amylolytic activity. <i>L. plantarum </i>CRL 2106 and <i>E. durans </i>CRL 2122 showed the highest phytase activity, which is of importance for mineral bioavailability. <i>L. plantarum </i>CRL 2106 and CRL 2107 and <i>Lc. mesenteroides </i>subsp.<i> mesenteroides</i> CRL 2131 synthesized the highest concentrations of B₂ and B₉ vitamin (140-250 ng/mL). This study demonstrates the potential of LAB to improve the nutritional and functional values of pseudocereal-derived foods.

Nondairy beverage produced by controlled fermentation with potential probiotic starter cultures of lactic acid bacteria and yeast

This work aimed to develop a nondairy fermented beverage from a blend of cassava and rice based on Brazilian indigenous beverage cauim using probiotic lactic acid bacteria (LAB) and yeast. The indigenous strains Lactobacillus plantarum CCMA 0743 (from cauim) and Torulaspora delbrueckii CCMA 0235 (from tarubá), and the commercial probiotic, L. acidophilus LAC-04, were used as starter cultures in single and co-cultivations. The bacteria populations were around 8.0 log (CFU/mL) at the end of all fermentations as recommended for probiotic products. Higher residual starch contents were noted in the single LAB cultures (10.6% [w/w]) than in co-cultures (<6% [w/w]), showing that co-culture may help the digestibility. For all different assays (single and co-culture), lactic acid was the main organic acid detected (>1.6g/L) and ethanol was lower than 0.5% (w/v) consisting in a non-alcoholic beverage. The assays containing yeast showed the highest antioxidant activity (around 10% by DPPH and ABTS methods). Therefore, a nondairy fermented beverage was successfully obtained, and the co-culture of LAB and T. delbrueckii could increase the product's functional properties.