1,720,980 research outputs found
Microbiological quality of ethnic ready-to-eat foods sold in Tuscany: preliminary results
No full textIn recent years, consumers who enjoy ethnic foods have increased in number and ethnic restaurants have become popular in Europe and also in Italy. From 2011 to 2014, this catering sector grew by 1.6%. It counts about 190,000 throughout the country and this number is expected to grow [1]. The aim of this study was to evaluate the microbiological quality of some ethnic ready-to-eat foods retailed in Tuscany. From September 2016 to March 2017, 185 food samples were collected from take-away shops in 4 Tuscany provinces (LI, LU, PI, PO). The samples included various types of ready-to-eat foods that were stored precooked for reheating on demand: 101 Chinese foods (47 pig/beef meat, 34 fish, 17 poultry meat and 3 eggs), 70 kebabs (35 sandwiches and 35 meat alone) and 14 Turkish or Indian foodstuff (8 poultry meat and 6 mixed meat). The food samples were analyzed within 4 hours after they were purchased. The analyses were focused on the main safety and hygiene indicator microorganisms. Enterobacteriaceae, Escherichia coli, coagulase-positive staphylococci (CPS), Salmonella spp., Listeria monocytogenes and Yersinia enterocolitica were investigated using the methods prescribed by the relevant ISO standards. All samples were negative for Salmonella spp. and L. monocytogenes. Y. enterocolitica was isolated from one Chinese sample, a fish soup. As concern CPS, 82/185 samples (44.32%) presented bacterial counts under detectable limit, 84/185 (45.40%) between 102 and 105 CFU/g and 19/185 (10.27%) above 105 CFU/g. Regarding Enterobacteriaceae 102/185 samples (55.13%) showed bacterial counts under detectable limit, 63/185 (34.05%) between 102 and 105 CFU/g and 20/185 (10.81%) exceeding 105 CFU/g. For E. coli, 168/185 samples (90.81%) presented bacterial counts under detectable limit and 17/185 (9.19%) between102 and 105 CFU/g. A percentage of 4.86% samples showed bacterial counts above 105 CFU/g for both CPS and Enterobacteriaceae, specifically 6 Chinese foods (2 pig/beef meat, 2 poultry meat, 2 fish) and 3 kebab sandwiches. The results of this investigation show that all samples except one resulted negative for major bacterial pathogens, in accordance with studies of other authors [2;3]; besides many samples presented low bacterial contamination. However, few samples showed high bacterial contamination, especially for Enterobacteriaceae and CPS. Although final heating reduces the levels of microorganisms present in foods, it can’t inactivate any toxins if present. Hence, preliminary results suggest the need to improve good hygiene practices in take-away restaurants, in particular handling in ready-to-eat products.
[1] http://www.coldiretti.it/News/Pagine/612----6-Settembre-2015.aspx; [2] Catellani et al. Survey on the microbiological quality of Chinese food preparations. Vet Res Commun. 2010 34 Suppl 1, 183-7; [3] Nassi et al. Döner kebab retailed on the Lucca area: results of surveillance activity. A.I.V.I. Marzo 2010 n.7
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
Effect of an Italian propolis on the growth of Listeria monocytogenes, Staphylococcus aureus and Bacillus cereus in milk and whey cheese
Full text linkPropolis antimicrobial activity has been limitedly studied in food, particularly in dairy products. We studied the antimicrobial activity of an alcoholic extract of an Italian propolis in sterile skim milk, pasteurized cow’s milk, and cow’s and goat’s whey cheese (ricotta). Following the determination of the minimal inhibitory concentration on Gram+ and Gram-bacteria, the extract was employed at 2 and 5% (P2, P5), using controls with the same ethanol concentrations (E2, E5) and without any addition. In milk trials, Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, and Pseudomonas fluorescens were tested. P2 and P5 samples registered significant decreases of Gram+ bacteria in skim milk. The same was true for P5 in cows’ milk, but only with S. aureus for P2. Ricotta was inoculated with L. monocytogenes, S. aureus and B. cereus and stored at 8.5°C. In cow’s milk ricotta, L. monocytogenes counts in P5 were always lower than control during the storage time, significantly so from the 14th day. In goat’s ricotta, L. monocytogenes counts in P5 were at least one logarithm lower than E5, whereas the extract didn’t show a significant effect on S. aureus and B. cereus. The antimicrobial activity of propolis, particularly on L. monocytogenes, could be employed in ready-to-eat refrigerated dairy products
Antimicrobial and anti-biofilm activity of manuka essential oil against Listeria monocytogenes and Staphylococcus aureus of food origin
No full textThe activity of manuka (Leptospermum scoparium) essential oil (EO) on biofilms of foodborne Listeria monocytogenes and Staphylococcus aureus has been studied. Seven strains of L. monocytogenes and 7 of S. aureus (5 methicillin-resistant) were tested. EO minimal inhibitory concentration (MIC), EO minimal bactericidal concentration (MBC) and biofilm production quantification were determined for each strain by microtiter methods. Moreover, EO Minimum Biofilm Inhibitory Concentration (MBIC) and Minimum Biofilm Eradicating Concentration (MBEC) were determined on 2 L. monocytogenes and 3 S. aureus that showed the best biofilm production. Finally, on 4 strains out of 5 (2 L. monocytogenes and 2 S. aureus) EO Biofilm Reduction Percentage (BRP) vs. untreated controls was assessed after a treatment with EO subinhibitory concentrations. The chemical composition of manuka essential oil was determined by Gas Chromatography- Electron Impact Mass Spectrometry (GCEIMS). The manuka EO demonstrated good antimicrobial activity: L. monocytogenes MIC and MBC were 0.466 mg/ml and 0.933 mg/ml, respectively, whereas S. aureus MIC and MBC were 0.233 mg/ml and 0.466 mg/ml, respectively. Furthermore, L. monocytogenes showed a MBIC of 0.933 mg/ml and a MBEC in the range of 0.933–1.865 mg/ml, whereas S. aureus had a MBIC in the range of 7.461–14.922 mg/ml and a MBEC of 14.922 mg/ml. L. monocytogenes revealed no significant BRP after the treatment with manuka EO, whereas S. aureus showed a BRP higher than 50% with MIC/2 and MIC/4 EO concentrations. These results provide information for feasible manuka EO applications in food production systems
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
CHARACTERISATION OF PGI LARDO DI COLONNATA
No full textTo characterize Lardo di Colonnata IGP, 24 samples of lard, obtained from 3 producers of Consortium, have been analyzed during the 6 months of ripening, from raw material to finished product. The results of microbiological and physical-chemical analyses confirm that this product is characterized by early stability, attributable to the composition of the product itself, composed of over 90% lipids, and to the production technology
Bee-pollen retailed in Tuscany (Italy): Labelling, palynological, microbiological, and mycotoxicological profile
Full text linkBee pollen is the result of flower pollen collecting and processing by honey bees. Due to its nutritional profile, it is considered a functional food. The present work aimed at evaluating labelling, pH, Aw, microbiological and mycotoxicological profile of 29 bee pollen samples (dried and fresh) purchased at retail in Tuscany (Italy). Only one pollen lacked more than two mandatory indications. Aw ranged from 0.19 to 0.77, while pH from 4.50 to 6.10. Fresh samples presented higher bacterial loads than dried samples. Total bacterial counts, Enterobacteriaceae, yeasts and molds and lactic acid bacteria ranges were 2.2–6.0, <2–4.1, <1–4 and <2–6.0 log CFU/g, respectively. Escherichia coli, Staphylococcus aureus, Bacillus cereus and sulphite-reducing clostridia loads were lower than the detection limit; Salmonella spp. and Listeria monocytogenes were always absent. As for mycotoxins, total aflatoxins were detected in all samples (5.2–34.4 μg/kg). Higher deoxynivalenol concentrations were detected (maximum: 179.7 μg/kg). Since the occurrence of spoilage microorganisms seems to be frequent, leading to possible alterations of the organoleptic profile, the microbiological quality of fresh bee pollen should be monitored. The risk related to the presence of pathogenic microorganisms seems to be very low, while attention must be paid to the presence of toxic metabolites
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