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Structure of lactic acid bacteria biota in ivy flowers, fresh bee-collected pollen (BCP), hive-stored bee bread, and honeybee gastrointestinal tract was investigated. Although a large microbial diversity characterized flowers and fresh BCP, most of lactic acid bacteria species disappeared throughout the bee bread maturation, giving way to Lactobacillus kunkeei and Fructobacillus fructosus to dominate long stored bee bread and honeybee crop. Adaptation of lactic acid bacteria was mainly related to species-specific, and, more in deep, to strain-specific features. Bee bread preservation seemed related to bacteria metabolites, produced especially by some L. kunkeei strains, which likely gave to lactic acid bacteria the capacity to outcompete other microbial groups. A protocol to ferment BCP was successfully set up, which included the mixed inoculum of selected L. kunkeei strains and Hanseniaspora uvarum AN8Y27B, almost emulating the spontaneous fermentation of bee bread. The strict relationship between lactic acid bacteria and yeasts during bee bread maturation was highlighted. The use of the selected starters increased the digestibility and bioavailability of nutrients and bioactive compounds naturally occurring in BCP. Our biotechnological protocol ensured a product microbiologically stable and safe. Conversely, raw BCP was more exposed to the uncontrolled growth of yeasts, moulds, and other bacterial groups.

The increasing demand for healthy baked goods boosted studies on sourdough microbiota with beneficial metabolic traits, to be used as potential functional starters. Here, yeast populations of traditional sourdoughs collected from four Tuscan bakeries were investigated. Among 200 isolated strains, 78 were randomly selected and molecularly characterized. Saccharomyces cerevisiae was dominant, representing the only species detected in three out of the four sourdoughs. The fourth one harbored also Kazachstania humilis. Inter-delta regions analysis revealed a high intraspecific polymorphism discriminating 16 biotypes of S. cerevisiae isolates, which clustered based on their origin. Representative isolates from each biotype group were individually used to ferment soft and durum wheat flour, aiming at evaluating their pro-technological, nutritional and functional features. During fermentation under standardized conditions, all strains were able to grow of ca. 2 log cycles, but only S. cerevisiae L10Y, D18Y and D20Y had a significantly shorter latency phase in both flours. Overall, the highest volumes were reached after 16 h of fermentation in both soft and durum fermented dough. S. cerevisiae D2Y produced the highest dough volume increase. K. humilis G23Y was the only strain able to increase the total free amino acids concentration of the doughs. Overall, values of phytase activity were significantly higher in durum compared to the corresponding soft fermented dough. K. humilis G23Y and S. cerevisiae D20Y, D24Y showed a threefold higher phytase activity than spontaneously fermented control, and the highest concentration of total phenols. Almost all the strains led to increases of antioxidant activity, without significant differences among them. Investigations on the resistance of the strains to simulated gastric and intestinal conditions, that is considered a pre-requisite for the selection of probiotics, revealed the ability to survive in vitro by many of the strains considered. This study proposed the best performing yeast strains selected among autochthonous sourdough yeasts based on their pro-technological, nutritional and functional traits to be used as starters for making sourdough baked goods or functional cereal-based beverages. Although some yeast strains combined several technological and nutritional traits, the association of more selected strains seemed to be a requisite to get optimal sourdough characteristics.

The novel cereal 'Tritordeum' was employed in sourdough fermentation for bread making using a traditional backslopping procedure over 10 days. Culture-dependent and culture-independent approaches were used to characterize microbial ecology during sourdough preparation and propagation. Sourdough reached the highest microbial diversity after three days of propagation. Microbial diversity decreased as sourdough reached maturity (day 5). Microbiota dominance shifted from Weissella to Lactiplantibacillus genera after 5 days of propagation. Lactic acid bacteria (LAB) showed a constant increase throughout the propagations starting from 3.9 ± 0.24 log CFU g

This study investigated the effectiveness of two novel started-assisted sauerkraut fermentations in comparison with spontaneous fermentation. Three lactic acid bacteria strains were selected as best starters for sauerkraut processing, based on the complementarity of pro-technological (kinetics of growth and acidification) traits, phenotypic fingerprints through OmniLog Phenotype MicroArray, and phenolics metabolism. The selected strains were applied according to two different fermentation methods based on steering sequential and temporally deferred inoculum of three strains, and ternary simultaneous inoculum. Sequential and ternary starters-assisted fermentations lasted 9 and 7 days, respectively, and were compared to conventional spontaneous fermentation lasting 35 days. Sequential and ternary fermentations resulted in a higher and constant number of lactic acid bacteria compared to spontaneous fermentation, which reflected on the acidification and sugar utilization. Ternary fermentation enhanced phenolic compounds conversion (hydrocaffeic acid, hydroferulic acid, 4-ethyl catechol), ensuring at the same time higher level of aliphatic (glucobrassicanapin) and indole glucosinolates (glucobrassicin) and derivatives(ascorbigen). Short fermentation of sequential and ternary starters-assisted processing caused only slight changes in the sensory profile compared to the spontaneous process, preserved the structural integrity of sauerkraut, and did not affect the colour lightness.

Robo advice has moved its first steps in the Anglo-Saxon countries and is now rapidly gaining market share at a global level. The phenomenon fueled a growing and still not conclusive institutional debate about potential benefits and risks to financial consumers, based also on investors’ biases and behaviours that online platforms could trigger to the detriment of robo advisees. The present paper provides some insights into attitudes and behaviours that might prevail in a digital environment among young investors, representing the category of users potentially more involved by the development of the automated advice. In detail, the study investigates whether individuals’ propensity to follow the recommendation received from an advisor changes depending on whether the advisor is a human or a robot. The analysis is based on data collected through an ad hoc developed laboratory experiment run in the Cesare Lab of LUISS University with a sample of 180 students. Students were given an initial monetary endowment and were asked to choose between six different portfolios of financial activities; after being profiled through a questionnaire aimed at eliciting their risk tolerance (Grable and Lytton’s Risk Tolerance Quiz; 2003), they received the advice, either from a human advisor or from a robo advisor (i.e. via a computer platform) depending on the treatment they had randomly assigned before entering the experimental session. Then, they were asked again to choose among the six portfolios in order to capture whether the propensity to follow the recommendation depends on its source (human versus robo). Finally, participants were asked to answer several questions eliciting risk preferences, financial literacy (actual and perceived) and digital literacy, serving as control variables when modelling the probability to follow the advice. Our results show that the probability to follow the advice does not depend on the source of the recommendation but rather on the alignment between the self-directed choice made before receiving the advice and the recommendation subsequently received: the propensity to follow the advisor (either human or robo) increases if the advice confirms individual’s own beliefs about her/his investor profile. This result might be explained by referring to individuals’ attitude towards the so called ‘confirmation bias’. However, when the self-directed choice differs from the recommendation received, participants may be more likely to follow the advice given by a human advisor and less likely to follow the advice formulated by an algorithm. Also the gender of the advisor seems to matter: women tend to follow the advice provided by a female advisor more frequently compared to the case of the recommendation given by a male advisor. This work is part of a wider research on FinTech that CONSOB started in 2016, in collaboration with several Italian universities, with the aim of exploring opportunities and risks for investor protection and the financial system as a whole, related to the application of technological innovation to the provision of financial services. In particular, supplementing Lener, Linciano and Soccorso (2019, edited by) and Caratelli et al. (2019), this document widens the field of investigation by referring to a specific target of the population - the so called millennials and post-millennials – and using complementary and innovative methods. According to an evidence-based approach, insights from the present study may suggest specific investor protection initiatives, also in terms of financial education activities designed for a clearly-identified segment of the population (the so called millennials and post-millennials, in this case). Evidence from the present work might be extended further with respect to the consumers’ perception of the fairness of algorithms used to provide financial services, the cognitive heuristics and biases underlying decision making process and investments in the digital environment and nudges which may be used to enhance investor protection.

Background Cheeses are inherently microbiologically and biochemically dynamic. Numerous biotic and abiotic drivers govern the establishment and assembly of a core microbiota in cheese, which, for internally-ripened cheeses, having an intermediate to long period of ripening, consists of starter and non-starter lactic acid bacteria (SLAB and NSLAB). The management of this dynamic ecosystem has to consider this core as a super-organism, which results from the sums of microbial metabolisms and interactions among individual microbes. Scope and approach This review focuses on all presumptive drivers, raw and pasteurized milk, farming system and house microbiota, and intrinsic and extrinsic factors during cheese manufacture and ripening, which qualitatively and mainly depending on the farm management system and cheese variety may influence the populations of SLAB and NSLAB. The interactions between these two microbial groups are described also. Key findings and conclusions The cheese ecosystem shows a variable flux of its core microbiota from milking through manufacture to ripening. Many and diverse drivers establish and assembly the lactic acid bacteria biota. If such drivers are efficient to guarantee microbial and cheese diversities, on the other hand, their control is the fundamental pre-requisite to synchronize and balance microbiological events. The methodological approaches (e.g., omics techniques and integrated system biology) have markedly improved to concretize this ambitious goal. Facing and improving the knowledge on the main drivers, the current step should focus on a unique puzzle of coexisting species/biotypes likely a super-organism, whose guide has to consider all casehardened microbial elements.

This study aimed to explore common purslane (Portulaca oleracea L.) as potential raw substrate to develop novel functional preparations through lactic acid fermentation. Different lactic acid bacteria were used as single starter. P. oleracea fermented with Lactobacillus kunkeii B7 and Lactobacillus plantarum POM1 resulted in decreased levels (ca. 30%) of oxalic acid, which is commonly recognized as an anti-nutritional compound. Lactobacillus brevis POM4 enhanced by ca. 400% the concentration of γ-amino butyric acid, a non-protein amino acid with various physiological functions. Fermentation of P. oleracea led to a marked increase of α-linalool, a monoterpene compounds with various pharmacological properties. Bioconversion of oleraceins by L. kunkeii B7 is likely responsible for the increased antioxidant activity. The decrease of polyunsaturated fatty acids potentially underlined the synthesis of various derivatives with potential health or nutritional effects. Hence lactic acid fermentation of P. oleracea is a powerful tool to achieve standardized functional foods.

Date fruit (Phoenix dactylifera L.) is a suitable raw matrix for manufacturing of functional ingredients. The aptitude of selected autochthonous lactic acid bacteria for manufacturing of freeze-dried powder from fermented date fruits puree as dietary supplement with health-promoting features was investigated. Fermentation of date fruits puree with selected Lactobacillus plantarum strains allowed the highest concentration of γ-amino butyric acid, conjugated fatty acids, and insoluble dietary fibers. The highest Trolox equivalent antioxidant activity was also induced. Lactic acid fermentation affected the profile of phenolic acids and flavonoids, enriching date fruits puree in phenolic derivatives with high human bioavailability. Fermented date fruits puree was also capable to modulate positively in vitro the growths of several cultivable gut microbial taxa, and enhanced the synthesis of short chain fatty acids. In conclusion, the lactic acid fermentation of date fruits is a suitable tool to achieve a standardized and marketable functional dietary supplement.

Extended use of antibiotics in dairy farming for therapeutic and prophylactic reasons, but also the higher prevalence of antibiotic resistant bacteria (ARB) in the farm environment raised the concern of consuming raw cow's milk and its derived products. The aim of this study was to predict by shotgun metagenomic analyses the presence of antibiotic resistance genes (ARGs) mainly correlated with Gram-negative bacteria in antibiotic residue free raw cow's milk derived exclusively from healthy animal from South Tyrol (Northern Italy), chosen as a model system. Assessment of shotgun metagenomic data of reconstructed scaffolds, revealed the existence of Pseudomonas spp. as the most abundant Gram-negative species in the raw cow's milk samples bearing ARGs. Besides, ARGs also linked to lactic acid bacteria such as Lactococcus sp. and Lactobacillus sp. ARGs correlated to microbiome found in milk samples conferred resistance towards aminoglycoside-streptothricin, beta-lactamase, macrolide, tetracycline, carbapenem, cephalosporin, penam, peptide, penem, fluoroquinolone, chloramphenicol and elfamycin antibiotics. Further bioinformatic processing included de-novo reassembly of all metagenomic sequences from all milk samples in one, to reconstruct metagenome assembled genomes (MAGs), which were further used to investigate mobile genetic elements (MGE). Analyses of the reconstructed MAGs showed that, MAG 9 (Pseudomonas sp1.) contained the oriT gene (origin of transfer gene) needed for transferring virulent factors. Although the presence of Pseudomonas is common in raw cow's milk, pasteurization treatment reduces their survivability. Nevertheless, attention should be paid on Pseudomonas spp. due to their intrinsic resistance to antibiotics and their capability of transferring virulent factors to other bacteria.