Changes in the microbial gene content and abundance can be analyzed to detect shifts in the microbiota composition due to the use of a starter culture in the food fermentation process, with the consequent shift of key metabolic pathways directly connected with product acceptance. Meat fermentation is a complex process involving microbes that metabolize the main components in meat. The breakdown of carbohydrates, proteins, and lipids can lead to the formation of volatile organic compounds (VOCs) that can drastically affect the organoleptic characteristics of the final products. The present meta-analysis, performed with the shotgun DNA metagenomic approach, focuses on studying the microbiota and its gene content in an Italian fermented sausage produced by using a commercial starter culture (a mix of and), with the aim to discover the connections between the microbiota, microbiome, and the release of volatile metabolites during ripening. The inoculated fermentation with the starter culture limited the development of and reduced the microbial diversity compared to that from spontaneous fermentation. KEGG database genes associated with the reduction of acetaldehyde to ethanol (EC 1.1.1.1), acetyl phosphate to acetate (EC 2.7.2.1), and 2,3-butanediol to acetoin (EC 1.1.1.4) were most abundant in inoculated samples (I) compared to those in spontaneous fermentation samples (S). The volatilome profiles were highly consistent with the abundance of the genes; elevated acetic acid (1,173.85 μg/kg), ethyl acetate (251.58 μg/kg), and acetoin (1,100.19 μg/kg) were observed in the presence of the starters at the end of fermentation. Significant differences were found in the liking of samples based on flavor and odor, suggesting a higher preference by consumers for the spontaneous fermentation samples. Inoculated samples exhibited the lowest scores for the liking data, which were clearly associated with the highest concentration of acetic acid. We present an advance in the understanding of meat fermentation by coupling DNA sequencing metagenomics and metabolomics approaches to describe the microbial function during this process. Very few studies using this global approach have been dedicated to food, and none have examined sausage fermentation, underlying the originality of the study. The starter culture drastically affected the organoleptic properties of the products. This finding underlines the importance of starter culture selection that takes into consideration the functional characteristics of the microorganism to optimize production efficiency and product quality.

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Bovine cysticercosis is caused by the larval stage of the human tapeworm Taenia saginata. According to European data on meat inspection, the prevalence ranges from 0.007% to 6.8%, but the real prevalence is considered to be at least 10 times higher. Laboratory confirmation of the etiological agent is based on gross, stereomicroscopic, and histological examination of submitted specimens. False identifications may occur, possibly because of death and degeneration of cysts, or because taeniid larvae and other tissue parasites, such as Sarcocystis spp., may cause similar macroscopic morphological lesions. Therefore, tests that can warrant sure identification of taeniid lesions and calcified cysts in the muscle are needed. The focus of our study was to develop a suitable postmortem test that could be applied on putative lesions by T. saginata cysticerci, as ambiguously diagnosed after routine meat inspection. In particular, we proposed a biomolecular assay targeting the mitochondrial cytochrome c oxidase subunit I gene (COI). For developing the polymerase chain reaction assay, viable cysts of Cysticercus bovis (n = 10) were used as positive reference samples, and those of Echinococcus granulosus (n = 3), Cysticercus tenuicollis (n = 3), and Sarcocystis spp. (n = 4) as reference negative controls. Further, to evaluate the applicability of the proposed assay, 171 samples of bovine muscular tissue, obtained from local slaughterhouses and containing lesions recognized as T. saginata cysticerci by macroscopic examination, were tested. The proposed test confirmed the diagnosis at postmortem inspection in 94.7% (162/171) of samples. In conclusion, the assay developed in this study, amplifying a short fragment from the mitochondrial gene COI, showed to be suitable for samples containing both viable and degenerating T. saginata cysticerci, yielding an unequivocal diagnosis.

Valle d'Aosta Lard d'Arnad is a protected designation of origin (PDO) product produced from fat of the shoulder and back of heavy pigs. Its manufacturing process can be very diverse, especially regarding the maturation temperature and the NaCl concentration used for the brine; thereby, the main goal of this study was to investigate the impact of those parameters on the microbiota developed during curing and ripening. Three farms producing Lard d'Arnad were selected. Two plants, reflecting the industrial process characterized either by low maturation temperature (plant A [10% NaCl, 2°C]) or by using a low NaCl concentration (plant B [2.5% NaCl, 4°C]), were selected, while the third was characterized by an artisanal process (plant C [30% NaCl, 8°C]). Lard samples were obtained at time 0 and after 7, 15, 30, 60, and 90 days of maturation. From each plant, 3 independent lots were analyzed. The diversity of live microbiota was evaluated by using classical plate counts and amplicon target sequencing of small subunit (SSU) rRNA. The main taxa identified by sequencing were Acinetobacter johnsonii, Psychrobacter, Staphylococcus equorum, Staphylococcus sciuri, Pseudomonas fragi, Brochothrix, Halomonas, and Vibrio, and differences in their relative abundances distinguished samples from the individual plants. The composition of the microbiota was more similar among plants A and B, and it was characterized by the higher presence of taxa recognized as undesired bacteria in food-processing environments. Oligotype analysis of Halomonas and Acinetobacter revealed the presence of several characteristic oligotypes associated with A and B samples.IMPORTANCE Changes in the food production process can drastically affect the microbial community structure, with a possible impact on the final characteristics of the products. The industrial processes of Lard d'Arnad production are characterized by a reduction in the salt concentration in the brines to address a consumer demand for less salty products; this can negatively affect the dynamics and development of the live microbiota and, as a consequence, can negatively impact the quality of the final product due to the higher abundance of spoilage bacteria. This study is an overview of the live microbiota that develop during lard manufacturing, and it highlights the importance of the use of traditional process to produce PDO from a spoilage perspective.

SummarySalmonella bongori 48:z 35 :-is considered endemic to Sicily (Italy) due to its epidemiological peculiarity. To our knowledge, no previous cases of human infection caused by S. bongori 48:z 35 :-have ever been reported in mainland Italy. Here we describe the isolation of S. bongori 48:z 35 :-from a 1-year-old symptomatic child in northwest Italy (Piedmont Region). The strain showed no antimicrobial resistance. Reporting of S. bongori 48:z 35 :-in a previously safe area is important to identify epidemiological changes. IntroductionStrains of Salmonella bongori with the antigenic formula 48:z 35 :-have been isolated from various different sources in Sicily: 23 children (aged 1 month to 3 years), an HIV-positive patient, a healthy human carrier, foodstuffs (soft cheese and hen's eggs), pigeons, blackcaps, and urban sewerage plants. In the majority of the human cases, illness occurred in infants and toddlers, manifesting with moderate to severe diarrhea and fever. One instance of infection with S. bongori 48:z 35 :-was reported in a dog with diarrhea in Calabria, Cosenza (southern Italy) in 1999. The apparently exclusive presence of S. bongori 48:z 35 :-strains suggests that this serovar is endemically circulating in Sicily (2,4).To our knowledge, no cases of human infection with S. bongori 48:z 35 :-have ever been reported outside Sicily. Elsewhere, the only recorded isolates were the isolation from a lizard in Chad in 1966, reported as the first isolated strain, and isolates from foodstuffs in England and Turkey (1,4).We report a recent case of infection with S. bongori 48:z 35 :-in a 1-year-old child in northwest Italy. Case ReportIn August 2014, a toddler was admitted to the Hospital of Alessandria (northwest Italy) because of severe haemorrhagic diarrhoea and fever. The remainder of the physical examination was unremarkable and hydration was normal. Bleeding punctate abrasions were seen on the perianal skin. Paracetamol was given. The child was hospitalised for 2 days and discharged after remission of symptoms. Treatment with ceftibuten for 4 days and probiotics for 10 days was prescribed. Blood and stool samples were sent to the hospital's microbiology laboratory for pathogen detection. Salmonella spp. strain was isolated and identified from the stool samples.The strain was subsequently typed as S. bongori 48:z 35 :-by the Regional Reference Laboratory for Salmonella typing according to the Kauffman-White and Le Minor scheme. S. bongori was confirmed by 16S rDNA sequencing using the MicroSEQ Full Gene system (Life Technologies). Antimicrobial resistance was verified by the disk diffusion method; the antibiotic used and their concentrations ( g) were: nalidixic acid (NAL, 30), ampicillin (A, 10), cefotaxime (CTX, 5), ceftazidime (CAZ, 10), amoxicillin/clavulanic acid 2:1 (AMC, 30), meropenem (MEM, 10), chloramphenicol (C, 30), gentamicin (G, 10), kanamycin (K, 30), streptomycin (S, 10), sulfonamides (Su, 0.25), tetracycline (T, 30), trimethoprim (TMP, 5), and trimethoprim-sulfamethoxazole (SXT, 1.25/23.7...