1,720,975 research outputs found
Recent Advances and Future Trends in Fermented and Functional Foods
No full textHealth and wellness are among the core segments of quickly-changing consumer goods, with ever-increasing health consciousness among consumers around the globe. Functional foods and beverages, formulated from natural ingredients with targeted physiological functions, are at the heart of research and development in the food industry. The application of modern biotechnology methods in the food and agricultural industry is expected to alleviate hunger today and help avoid mass starvation in the future. Modern food biotechnology has in recent years been transforming existing methods of food production and preparation far beyond the traditional scope. Currently, at the global level, food biotechnological research has focused on traditional process optimization (starter culture development, enzymology, fermentation), food safety and quality, nutritional quality improvement, functional foods, and food preservation (improving shelf life). The fermentation of substrates considered for human consumption has been applied for centuries as a process that enhances shelf life, sensory properties, and nutritional value. Special emphasis has also been given to newly growing concepts, such as functional foods and probiotics. The application of biotechnology in the food sciences has led to an increase in food production and has enhanced the quality and safety of food
Molecular Targets for Foodborne Pathogenic Bacteria Detection
No full textThe detection of foodborne pathogenic bacteria currently relies on their ability to grow on chemically defined liquid and solid media, which is the essence of the classical microbiological approach. Such procedures are time-consuming and the quality of the result is affected by the selectivity of the media employed. Several alternative strategies based on the detection of molecular markers have been proposed. These markers may be cell constituents, may reside on the cell envelope or may be specific metabolites. Each marker provides specific advantages and, at the same time, suffers from specific limitations. The food matrix and chemical composition, as well as the accompanying microbiota, may also severely compromise detection. The aim of the present review article is to present and critically discuss all available information regarding the molecular targets that have been employed as markers for the detection of foodborne pathogens. Their strengths and limitations, as well as the proposed alleviation strategies, are presented, with particular emphasis on their applicability in real food systems and the challenges that are yet to be effectively addressed
Study of the symbiosis of wild yeast and lactic acid bacteria strains in sourdough
No full textThe aim of this work was to study the physicochemical properties of sourdoughs, to identify the yeasts and lactic acid bacteria that form their microflora and study their metabolic properties, to design starter cultures in order to study their effect on organoleptic properties of sourdough bread and finally the study of interactions among dominant species as far as growth and production of metabolities are concerned. S. cerevisae was present in every sourdough tested in comparison with P. membranaefaciens, Y.lipolytica and D. hansenii. L. sanfranciscensis was present in the majority of the sourdoughs tested , L.brevis and W.confusa werer frequently present and finally L.paralimentarius , P.peritosaceus and E.faecium were also isolated. All yeast and lactic acid bacteria strains had a lack of a myolytic and proteolytic activity. Only Y. lipolytica strains exhibited lipolytic activity and all strains showed weak phytase activity. THe study of the flour mono and disaccharides fermentaton by the isolated wild strains led to the conclusion that this is an important feature as far as the stability of this specific microbial consortium is concerned. The formation of starter cultures including the isolated wild strains resulted in the production of traditional bread with good organoleptic features. Interactions between yeasts and lactic acid bacteria in sourdough have both synergistic and antagonistic character.Σκοπός της παρούσας εργασίας ήταν η μελέτη φυσικοχημικών και μικροβιολογικών χαρακτηριστικών παραδοσιακών ζυμαριών, η ταυτοποίηση των ζυμών και γαλακτικών βακτηρίων που απαρτίζουν την μικροχλωρίδα τους, η μελέτη μεταβολικών δραστηριοτήτων των μικροοργανισμών αυτών σε καλλιέργειες εκκίνητες ώστε να μελετηθεί η επίδραση τους στις οργανοληπτικές ιδιότητες του τελικού προϊόντος και η μελέτη των αλληλεπιδράσεων των μικροοργανισμών που επικρατούν στο παραδοσιακό ζυμάρι. Οι ζύμες που απομονώθηκαν ήταν η S. cerevisiae που επικρατούσε σε κάθε παραδοσιακό ζυμάρι , η P.membranae faciens, η Y.lipolytica και η D.hansenii. Τα γαλακτικά βακτήρια που απομονώθηκαν ήταν υο L. sarrTranciscensis που ήταν παρόν σχεδόν σε όλα τα παραδοσιακά ζυμάρια, τα L.brevis και W.confusa που απομονώθηκαν απο πολλ΄παραδοσιακά ζυμάρια και τα L. paralimentarius, P.pentosaceus και E. faecium. Σε όλα τα στελέχη ζυμών και γαλακτικών βακτηρίων διαπιστώθηκε έλλειψη αμυλολυτικής και πρωτεολυτικής δράσης. Λιπολυτική δράση ανιχνεύθηκε μόνο στα στελέχη της Y.lipolytica ενώ σε όλα τα στελέχη ανιχνεύθηκε ασθενής ενεργότητα φυτάσης. Ο καταβολισμός των υδατανθράκων του αλεύρου είναι σημαντικός παράγοντας για τη σταθερότητα του οικοσυστήματος. Η σύνθεση των μικροοργανισμών αυτών σε καλλιέργειες εκκίνητες οδήγησε στην παραγωγή παραδοσιακού ψωμιού με αξιόλογα οργανοληπτικά χαρακτηριστικά. Οι αλληλεπιδράσεις μεταξύ των ζυμών και των γαλακτικών βακτηρίων διακρίνονται από συνεργιστικό και ανταγωνιστικο χαρακτήρ
Recent Advances and Future Trends in Fermented and Functional Foods
Get PDFHealth and wellness are among the core segments of quickly-changing consumer goods, with ever-increasing health consciousness among consumers around the globe. Functional foods and beverages, formulated from natural ingredients with targeted physiological functions, are at the heart of research and development in the food industry. The application of modern biotechnology methods in the food and agricultural industry is expected to alleviate hunger today and help avoid mass starvation in the future. Modern food biotechnology has in recent years been transforming existing methods of food production and preparation far beyond the traditional scope. Currently, at the global level, food biotechnological research has focused on traditional process optimization (starter culture development, enzymology, fermentation), food safety and quality, nutritional quality improvement, functional foods, and food preservation (improving shelf life). The fermentation of substrates considered for human consumption has been applied for centuries as a process that enhances shelf life, sensory properties, and nutritional value. Special emphasis has also been given to newly growing concepts, such as functional foods and probiotics. The application of biotechnology in the food sciences has led to an increase in food production and has enhanced the quality and safety of food
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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