1,721,027 research outputs found
Research progress in the use of lactic acid bacteria as natural biopreservatives against Pseudomonas spp. in meat and meat products: A review
Full text linkMeat and meat products represent excellent sources of key nutrients for human health, such as protein, essential
amino acids, B vitamins, and minerals. However, they are recognized as highly perishable foods since they
represent an ideal substrate for the growth of spoilage and pathogenic microorganisms. Meat spoilage is a
complex process that involves multiple microorganisms and a combination of intrinsic and extrinsic ecological
factors. One of the most common causative agents of meat spoilage is represented by species of the genus
Pseudomonas. To prevent the development of such undesired microorganisms, chemical preservatives are usually
exploited by the meat industry. However, the growing consumers’ concerns about potential health issues linked
to the consumption of chemical preservatives has prompted the food industry to develop alternative strategies to
prevent microbial spoilage in meat and meat products. Besides to the application of physical strategies, the
interest towards the use of natural preservatives, such as bioprotective microorganisms (e.g., lactic acid bacteria)
and their metabolites, has rapidly grown. When used in meat and meat-based products, lactic acid bacteria
exhibited a bioprotective activity against spoilage and even foodborne pathogens, thanks to the production of
different inhibitory compounds including organic acids, bacteriocins, carbon dioxide, hydrogen peroxide,
ethanol, N-diacetyl, and lactones. This bioprotective activity might justify the use of lactic acid bacteria or their
metabolites as natural preservatives to extend the shelf-life of the products. However, the effectiveness of
antimicrobial activity against Pseudomonas in meat and meat products still needs to be investigated to understand
the influence of the type of end product, the type of packaging, and the storage conditions (time and temperature).
Moreover, the antimicrobial activity of lactic acid bacteria must also be evaluated taking into consideration
their ability to maintain the sensory features of fresh meat (whether whole or minced), without
negatively affecting its sourness and acidity. Of note, the results herein discussed emphasize the challenges
occurred in translating in vitro findings into practical applications due to the complex interactions between
bacteria, antimicrobial compounds, and food matrices
Effect of process parameters on the production of lactic acid bacteria in batch fermentation
Full text linkThe effect of aeration and type of neutralising agent on the growth of lactic acid bacteria, isolated from a typical Italian cheese, was investigated in laboratory fermenters, with the aim of defining process conditions for the production of autochthonous cultures to be used as starters in traditional cheese-making. Batch fermentation trials were carried out using six different bacterial species belonging to the genera Lactobacillus, Lactococcus and Leuconostoc on lactose or glucose based substrates, with sodium-hydroxide (NaOH) or ammonium-hydroxide (NH4OH) as neutralisers and with or without micro-aeration 0.15 vvm. In most cases, optimal conditions for growth were observed in the presence of both ammonium and air supply. The specific growth rate (mu(max)) values required for growth ranged from 0,16 to 0.39 h(-1)
Fermentation of House Crickets (Acheta domesticus): Boosting Quality and Functionality in Cricket-Based Food Ingredients
Full text linkThis review examines the nutritional and functional potential of Acheta domesticus, the impact of fermentation on its biochemical and microbiological properties, and its application in food ingredients and products. Relevant literature was reviewed on the composition, fermentation behavior, product development, and consumer perceptions related to cricket-based ingredients, with a focus on fermented applications and microbiota interaction. Fermentation improves the safety, digestibility, flavor, and nutritional value of cricket powder. Lactic acid bacteria (e.g., Lactiplantibacillus plantarum and Latilactobacillus curvatus) enhanced substrate acidification, reduced biogenic amines and acrylamide levels, and contributed to desirable volatile compounds production. Additionally, fermentation using yeasts like Yarrowia lipolytica and Debaryomyces hansenii resulted in the production of antimicrobial substances, reduction in chitin, and an increase in the matrix digestibility. Fermented cricket-based ingredients have been successfully applied to bread, biscuits, yogurt, and beverages. Protein hydrolysates produced by fermentation exhibited antioxidant, anti-aging, and preservative properties, expanding potential beyond food. Consumer acceptance was highest when insects were integrated into familiar and visually unobtrusive food formats. To conclude, A. domesticus shows great promise as a sustainable and functional food ingredient. Fermentation offers a key strategy to overcome safety, sensory, and acceptability barriers
Identificazione con PCR multipla di stipiti di enterococchi isolati da produzioni lattiero-casearie in Umbria
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Prevalence and risk factors for thermotolerant species of Campylobacter in poultry meat at retail in Europe
No full textThe thermotolerant species Campylobacter
jejuni, Campylobacter coli, Campylobacter lari
and Campylobacter upsaliensis are the causative agents
of the human illness called campylobacteriosis. This infection
represents a threat for the health of consumers
in Europe. It is well known that poultry meat is an
important food vehicle of Campylobacter infection. As
emerged from the reported scientific literature published
between 2006 and 2016, poultry meat sold at
retail level in Europe represents an important source
of the pathogen. The contamination level of poultry
meat sold at retail can vary depending on pre- and
post-harvest factors. Among the pre-harvest measures,
strict biosecurity practices must be guaranteed; moreover,
among post-harvest control measures scalding,
chilling and removal of faecal residues can reduce the
contamination level of Campylobacter. An additional issue
is represented by increasing proportion of Campylobacter
isolates resistant to tetracyclines, ciprofloxacin,
and nalidixic acid, thus feeding a serious concern on the
effectiveness of antibiotic treatment for human campylobacteriosis
in a near future
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