Prevalence and risk factors for thermotolerant species of Campylobacter in poultry meat at retail in Europe

Abstract The 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

Contribution of the autochthonous lactic acid bacteria population in a\ud production of raw milk Mozzarella cheese- CONTRIBUTO DELLA POPOLAZIONE LATTICA AUTOCTONA\ud IN UNA PRODUZIONE DI MOZZARELLA AL LATTE CRUDO\ud CON STARTER TERMOFILI COMMERCIALI

Mozzarella cheese is one of the most popular members of the Pasta Filata cheeses.The present research was aimed at\ud investigating the microbial population of a raw milk Mozzarella cheese manufacture\ud produced in the hinterland of the Marche region by using a commercial starter\ud culture of thermophilic cocci. At this aim, both molecular and phenotypic\ud assays were performed. The polyphasic approach utilized revealed an high diversity\ud of the autochthonous LAB population investigated, both at the species and\ud strain level.\ud Keywords: Mozzarella cheese, autochthonous lactic acid bacteria, RAPD, PFGE,\ud acidifying activit

Fermentation of Microalgal Biomass for Innovative Food Production

Fermentation is an ancient method used worldwide to process and preserve food while enhancing its nutraceutical profile. Alga‐based fermented products have recently been developed and tested due to growing interest in healthy sustainable diets, which demands the development of innovative practices in food production, operating for both human health and Earth sustainability. Algae, particularly microalgae such as Arthrospira platensis, Chlorella vulgaris, and Dunaliella salina, are already cultivated as sources of food due to their valuable compounds, including proteins, pigments, lipids, carotenoids, polyunsaturated fatty acids, steroids, and vitamins. Due to their nutritional composition, functional diversity, and flexible metabolism, microalgae represent good fermentation substrates for lactic acid bacteria (LAB) and yeasts. This review presents an overview of the scientific studies on microalga fermentation underlining microalgae’s properties and health benefits coupled with the advantages of LAB and yeast fermentation. The potential applications of and future perspectives on such functional foods are discussed

Parameters of flow in porous alluvial aquifers evaluated by tracers

Dye tracer tests, DNA biotracer, alluvial aquifer Marche, multiwell tests

Hydraulic contacts identification in the aquifers of limestone ridges: tracer tests in the Montelago pilot area (Central Apennines)

The investigated area, located in the inner part of the Marche region (central Italy) and belonging to the carbonate Umbria- Marche ridges in the central Apennines, is characterised by very complex geo-structural setting and widespread karst phenomena that make difficult the definition of the relation among the aquifers basing only on the hydrogeological survey. Hence, the presence of different flowpaths among aquifers of the Umbria-Marche hydrostratigraphic sequence and of tectonic contacts among the different structures is verified using tracer tests. In particular, the tests showed that the Calcare Massiccio and the Maiolica aquifers are connected under certain tectonic conditions. A new tracer given by a single stranded DNA molecule and traditional fluorescent dyes have been injected into the Montelago sinkhole in different periods (during the recharge and during the discharge) and recovered in several points along the expected hydrogeological basin, using either manual and automatic sampling. Fluorescent traps were positioned in creeks, rivers and springs. The DNA molecule is useful to trace surface water and groundwater, is detectable even at very low concentrations, no significant change in water density and viscosity can be observed and its use is not dangerous for the environment. The results stress the suitability of DNA as hydrogeological tracer, capable to identify connections among aquifers and study different flowpaths even in high flow conditions when traditional tracers are more and more diluted. Moreover, fluorescein tracer allowed for the transport parameter determination, giving mean velocities ranging from 100 to 3000 m/day and mean residence time from some tens to hundreds of hours, and determining the aquifer volumes

Lactic acid bacteria and yeasts from wheat sourdoughs of the Marche region

The need for a greater diversification of baked products has given rise to the on-going search for yeast and lactic acid bacteria (LAB) strains with optimal baking potential. Thirty-six yeasts and 118 LAB, isolated from nine type I sourdoughs that were sampled in bakeries located in the Marche region (central Italy), were molecularly and phenotypically characterized. The polyphasic approach used revealed the biodiversity of the microbial communities investigated and two yeasts and ten LAB cultures with the potential to be used in sourdough bread-making processes were identified

Exploitation of Tenebrio molitor larvae as biological factories for human probiotics, an exploratory study

The exploitation of yellow mealworm (Tenebrio molitor) larvae for the bioaugmentation of probiotic Bacillus clausii strains was evaluated during a 7-day rearing period. qPCR was applied to evaluate the persistence and growth of B. clausii in the rearing substrate and larvae (washed and non-washed). Moreover, the effect of freeze-drying of larvae on B. clausii viability was evaluated. The results demonstrated the suitability of yellow mealworm as biological factories for the multiplication of B. clausii through a simple and inexpensive procedure, in view of the further application of larvae as foods and food ingredients. In more detail, an increase in the load of B. clausii was observed during the 7-day rearing of larvae fed wheat middlings spiked with 1 Log cells g−1. Further research is needed to evaluate the most suitable technologies and processing parameters for obtaining yellow mealworm-based ingredients with a stable and active population of probiotic B. clausii

Study of the bacterial diversity of foods: PCR-DGGE versus LH-PCR

The present study compared two culture-independent methods, polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) and length-heterogeneity polymerase chain reaction (LH-PCR), for their ability to reveal food bacterial microbiota. Total microbial DNA and RNA were extracted directly from fourteen fermented and unfermented foods, and domain A of the variable regions V1 and V2 of the 16S rRNA gene was analyzed through LH-PCR and PCR-DGGE. Finally, the outline of these analyses was compared with bacterial viable counts obtained after bacterial growth on suitable selective media. For the majority of the samples, RNA-based PCR-DGGE revealed species that the DNA-based PCR-DGGE was not able to highlight. When analyzing either DNA or RNA, LH-PCR identified several lactic acid bacteria (LAB) and coagulase negative cocci (CCN) species that were not identified by PCR-DGGE. This phenomenon was particularly evident in food samples with viable loads b 5.0 Log cfu g−1 . Furthermore, LH-PCR was able to detect a higher number of peaks in the analyzed food matrices relative to species identified by PCR-DGGE. In light of these findings, it may be suggested that LH-PCR shows greater sensitivity than PCR-DGGE. However, PCR-DGGE detected some other species (LAB included) that were not detected by LH-PCR. Therefore, certain LH-PCR peaks not attributed to known species within the LH-PCR database could be solved by comparing them with species identified by PCR-DGGE. Overall, this study also showed that LH-PCR is a promising method for use in the food microbiology field, indicating the necessity to expand the LH-PCR database, which is based, up to now, mainly on LAB isolates from dairy produc