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Fishery products are highly perishable foods because of activity of spoilage and pathogenic microbiota, which can rapidly grow under the usually adopted storage conditions (mainly low temperature and application of modified atmosphere or vacuum). For this reason, the need of prolonging their shelf life is crucial to improve their commercialization, reducing food losses, and assuring their safety. Among the strategies to reach this aim, the application of “natural” approaches received an increasing interest due to their relatively low costs and the acceptance by consumers. In this chapter, two of these possible strategies are reviewed. The use of essential oils can delay or inhibit the growth of undesirable microorganisms because of the antimicrobial activity of many of their components. On the other side, also the use of bioprotective cultures has been described, with particular emphasis on the bacteriocin producing lactic acid bacteria. Both these strategies have received a wide scientific interest in the last decade. Nevertheless, relatively few are practical and industrial applications based on essential oils and bioprotective cultures. Here, the advantages and the potentiality of these approaches are reviewed together with the weaknesses, which limit their application to real foods.

We discuss the $p$- and the $hp$-versions of the virtual element method for the approximation of eigenpairs of elliptic operators with a potential term on polygonal meshes. An application of this model is provided by the Schr\"odinger equation with a pseudo-potential term. We present in details the analysis of the p-version of the method, proving exponential convergence in the case of analytic eigenfunctions. The theoretical results are supplied with a wide set of experiments. We also show numerically that, in the case of eigenfunctions with finite Sobolev regularity, an exponential approximation of the eigenvalues in terms of the cubic root of the number of degrees of freedom can be obtained by employing $hp$-refinements. Importantly, the geometric flexibility of polygonal meshes is exploited in the construction of the $hp$-spaces., Comment: 25 pages, 7 figures

The high quantity of spontaneous fermented sausages from different Mediterranean European Countries represents a relatively unexplored reservoirs of microbial biodiversity within which it is possible to find new microorganisms with relevant technological properties. With this aim, several spontaneously fermented European meat products have been collected from artisanal producers in Italy, Spain, Slovenia and Croatia and analysed for their chemicophysical, aromatic and safety features. Moreover, their microbial populations have been studied both with cultivation-dependent and metagenomic techniques in order to highlight the richness of microbial biodiversity. The results showed that each product differed in terms of aromatic and microbiological characteristics depending on the raw material quality and type, recipes, production techniques and fermentation and maturation conditions. In addition, the lactic acid bacteria biodiversity found can valorise the bacterial genetic heritage present in Mediterranean fermented products. In fact, the exploitation of these microbial biodiversity by bioprospecting of strains isolated from these environments can represent an effective strategy to find strains of industrial importance, filling the gap between the laboratory results and efficacy in the production field, being autochthonous strains more suitable for adaptation in specific ecological niches.

To assess whether angiotensin-converting enzyme inhibitors and third-generation dihydropyridine calcium channel blockers ameliorate diabetic complications, we compared glomerular filtration rate (GFR; primary outcome), cardiovascular events, retinopathy, and neuropathy in 380 hypertensive type 2 diabetics with albuminuria 2 (IQR: 0.16–0.50 mL/min per 1.73 m 2 ) on combined therapy, 0.36 mL/min per 1.73 m 2 (IQR: 0.18–0.53 mL/min per 1.73 m 2 ) on delapril, and 0.30 mL/min per 1.73 m 2 (IQR: 0.12–0.50 mL/min per 1.73 m 2 ) on placebo ( P =0.87 and P =0.53 versus combined therapy or delapril, respectively). Similar findings were observed when baseline GFR values were not considered for slope analyses. Albuminuria was stable in the 3 treatment groups. The hazard ratio (95% CI) for major cardiovascular events between combined therapy and placebo was 0.17 (0.04–0.78; P =0.023). Among 192 subjects without retinopathy at inclusion, the hazard ratio for developing retinopathy between combined therapy and placebo was 0.27 (0.07–0.99; P =0.048). Among 200 subjects with centralized neurological evaluation, the odds ratios for peripheral neuropathy at 3 years between combined therapy or delapril and placebo were 0.45 (0.24–0.87; P =0.017) and 0.52 (0.27–0.99; P =0.048), respectively. Glucose disposal rate decreased from 5.8±2.4 to 5.3±1.9 mg/kg per min on placebo ( P =0.03) but did not change on combined or delapril therapy. Treatment was well tolerated. In hypertensive type 2 diabetic patients, combined manidipine and delapril therapy failed to slow GFR decline but safely ameliorated cardiovascular disease, retinopathy, and neuropathy and stabilized insulin sensitivity.

Biogenic amines (BAs) are molecules, which can be present in foods and, due to their toxicity, can cause adverse effects on the consumers. BAs are generally produced by microbial decarboxylation of amino acids in food products. The most significant BAs occurring in foods are histamine, tyramine, putrescine, cadaverine, tryptamine, 2-phenylethylamine, spermine, spermidine, and agmatine. The importance of preventing the excessive accumulation of BAs in foods is related to their impact on human health and food quality. Quality criteria in connection with the presence of BAs in food and food products are necessary from a toxicological point of view. This is particularly important in fermented foods in which the massive microbial proliferation required for obtaining specific products is often relater with BAs accumulation. In this review, up-to-date information and recent discoveries about technological factors affecting BA content in foods are reviewed. Specifically, BA forming-microorganism and decarboxylation activity, genetic and metabolic organization of decarboxylases, risk associated to BAs (histamine, tyramine toxicity, and other BAs), environmental factors influencing BA formation (temperature, salt concentration, and pH). In addition, the technological factors for controlling BA production (use of starter culture, technological additives, effects of packaging, other non-thermal treatments, metabolizing BA by microorganisms, effects of pressure treatments on BA formation and antimicrobial substances) are addressed. © 2016 Gardini, özogul, Suzzi, Tabanelli and özogul.

Obiettivo di questo lavoro era lo studio dell´evoluzione della carica microbica totale e psicrotrofa indesiderata nel latte per produzione di Grana Trentino al variare del sistema di raccolta del latte. Il conferimento due volte al giorno del latte raccolto in bidoni senza refrigerazione o in cisterna refrigerata a 18°C è stato confrontato con il conferimento una volta al giorno del latte raffreddato alla stalla a 8 o 12°C. I latti sono stati seguiti dalla stalla alla caldaia, i campioni di latte e panna sono stati analizzati tramite tecniche classiche e molecolari per la definizione del quadro microbico. La composizione microbica del latte intero non differiva nelle 4 tesi: in tutti i campioni sono stati trovati S. thermophilus, L. helveticus, L. delbrückii, L. rhamnosus, Ln. mesenteroides, E. coli, specie appartenenti alla famiglia delle Pseudomonadaceae. Dopo l´affioramento, il latte a 12 o 8°C alla stalla aveva un quadro microbiologico sovrapponibile a quello del latte refrigerato a 18°C. Nel latte non refrigerato trasportato con bidoni le cariche batteriche totali in caldaia erano più alte rispetto ai latti refrigerati. La refrigerazione del latte a 12 o 8°C non ha comportato una dominanza dei batteri psicrotrofi sui lattici nel latte in caldaia. Durante l’affioramento notturno i microrganismi psicrotrofi aumentano solo in latti non refrigerati alla stalla, e le specie microbiche si distribuiscono differentemente nelle frazioni che si separano: Pseudomonas e Flavobacteriaceae maggiormente concentrati nella panna, Enterobacteriaceae e Streptococcaceae nella fase meno grassa.

La composizione microbica del Grana Trentino e del suo siero-innesto è stata studiata non solo in relazione alla differente tecnologia di raccolta e conservazione del latte ma anche in relazione al tempo di stagionatura e alla zona di campionamento. Per una serie di lavorazioni si è determinata la composizione microbica di latte, siero e di due forme gemelle, aperte dopo 9 e 18 mesi. Queste sono state tagliate lungo l’asse verticale e sono state campionate tre diverse zone lungo la diagonale: sotto la crosta, al centro e in posizione mediana. I campioni sono stati analizzati tramite metodi coltura-dipendenti e coltura-indipendenti (DGGE e 454 pyrosequencing) e i risultati sono stati messi in relazione con le analisi chimiche degli acidi grassi a corta catena. Batteri termofili sono stati trovati, come atteso, in grandi quantità sia nel siero cotto che nel siero-innesto. Dopo 9 mesi le conte erano più alte che dopo 18, e nel centro erano più basse che nelle altre due zone campionate. Le principali specie isolate da formaggio, all’analisi fenotipica, erano diverse da quelle isolate da latte e siero. Il microbiota nel sotto crosta e nella zona intermedia era dominato da Lactobacillus paracasei e Lactobacillus rhamnosus, mentre al centro vi era una maggiore presenza di Lb. rhamnosus. Dopo 18 mesi, i batteri lattici (LAB) erano assenti. L’analisi tramite pyrosequencing 454 ha permesso di individuare la dominanza di Streptococcaceae nella parte centrale delle forme di 18 mesi.

The aim of this work was to assess if a sub-lethal high pressure homogenization (HPH) treatment could modulate in vitro functional and biological properties of probiotic bacteria. Lactobacillus paracasei A13, Lactobacillus acidophilus 08 and Dru, Lactobacillus delbrueckii subsp. lactis 200 and bile-resistant derivatives L. acidophilus Druþ and L. delbrueckii subsp. lactis 200þ were suspended in phosphate buffered saline solution and treated at 50 MPa. Data obtained showed that HPH can modulate hydrophobicity and auto-aggregation without modification of viability and decarboxylase activity. Resistance to simulated gastric conditions resulted strain-dependent. High resistance was observed for treated L. paracasei A13, L. acidophilus Dru and 08 and L. delbrueckii subsp. lactis 200. The HPH-treatment reduced the resistance to simulated stomach duodenum-passage of L. acidophilus Dru while increased it for L. paracasei A13. Strain viability and resistance to simulated gastric conditions were evaluated treating at 50 MPa cells suspended in acidified buttermilk (pH 4.6) and stored at 4 C for 30 days. The highest cell viability loss, after 30 d of refrigerated storage, was observed for L. acidophilus Dru, independently of the application of HPH. However, after 30 days of storage, the resistance of L. paracasei A13 to simulated gastric digestion significantly increased in HPH treated cells. Fil: Tabanelli, G.. Interdipartimental Center of Industrial Research (CIRI Agroalimentare); Italia Fil: Patrignani, F.. Universidad de Bologna; Italia Fil: Vinderola, Celso Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Lactología Industrial. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Lactología Industrial; Argentina Fil: Reinheimer, Jorge Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Lactología Industrial. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Lactología Industrial; Argentina Fil: Gardini, F.. Universidad de Bologna; Italia Fil: Lanciotti, R.. Universidad de Bologna; Italia

This research is devoted to mass conservation and CFL properties of the Finite Elements Immersed Boundary Method. We first explore an enhanced higher order scheme applied to the Finite Element Immersed Boundary Method technique introduced by Boffi and Gastaldi. This technique is based on a Pointwise (PW) formulation of the kinematic condition, and higher order elements show better conservation properties than the original scheme. A further improvement with respect to the classical PW formulation is achieved introducing a fully variational Distributed Lagrange Multiplier (DLM) formulation. Numerical experiments show that DLM is not affected by any CFL condition. Furthermore the mass conservation properties of this method are extremely competitive.

The aim of this paper is to understand the performances of different finite elements in the space discretization of the Finite Element Immersed Boundary Method. In this exploration we will analyze two popular solution spaces: Hood-Taylor and Bercovier- Pironneau (P1-iso-P2). Immersed boundary solution is characterized by pressure discontinuities at fluid structure interface. Due to such a discontinuity a natural enrichment choice is to add piecewise constant functions to the pressure space. Results show that P1 + P0 pressure spaces are a significant cure for the well known “boundary leakage” affecting IBM. Convergence analysis is performed, showing how the discontinuity in the pressure is affecting the convergence rate for our finite element approximation.