Search

There is an increasing trend among food business operators to use natural flavorings in meat preparation to reduce microbial spoilage and extend the shelf life. The objective of this study was to evaluate the prevalence of the use of natural flavoring mixtures in meat preparation, the possible presence of additives in natural flavorings, and the assessment of any transfer of additives contained in natural flavorings into experimentally prepared beef burgers. Based on a preliminary survey conducted as part of the study, approximately 87% of establishments used natural flavoring mixtures in meat preparation. The same natural mixtures used by local industries were added to minced meat in order to produce experimental hamburgers. Citric acid was found in both natural flavoring mixtures ranging from 1760 mg/kg to 92,731 mg/kg and experimental burgers ranging from 57 mg/kg to 2248 mg/kg. Ascorbic acid was present in all natural flavoring mixtures from 260 mg/kg to 98,858 mg/kg but was recovered in three burgers up to 1075 mg/kg. Acetic acid was found in three flavoring mixtures (range 23,539-77,421 mg/kg) and transferred to three treated burgers (range 3063-3202 mg/kg). Nitrite was never found in hamburgers and only once in a natural flavoring mixture at a dose of 26 mg/kg, whereas nitrate was found in some natural flavoring mixtures up to 788 mg/kg but never in hamburgers. The study has raised some critical issues about the appropriate and conscious use of natural flavorings and the possible inadequate meat preparation labeling in the Umbria region.

Pork meat and processed pork products have been linked to multiple listeriosis outbreaks worldwide during the past years. Specifically, it has been highlighted that minced pork meat is easily perishable and may increase the growth of Listeria monocytogenes, which could be harmful to the general public's health. This study aimed to investigate the potential application of olive oil mill wastewater polyphenolic and red beet extracts as natural antimicrobial agents for L. monocytogenes growth control in burgers. The minced pork meat was mixed with the extracts and experimentally inoculated with L. monocytogenes, then molded into vacuum-packaged and cold-stored (4±1°C) burgers kept under alternating exposure to fluorescent light. The L. monocytogenes enumeration was performed on burgers at 0, 2, 5, and 10 days of shelf life. In uninoculated burgers, physicochemical (pH, water activity, color) and sensory determination (descriptive sensory analysis) were also conducted. At the end of storage, the samples treated with olive-derived extract showed the lowest value of L. monocytogenes (approximately 1.3 Log CFU/g). The physicochemical and sensory traits of burgers have benefited from the addition of both olive-derived and red beet extracts. Results suggest that olive mill wastewater polyphenolic extracts could be added to minced pork meat products to act as a natural antimicrobial agent.

In recent years, there has been an increased interest in substances that could inhibit or reduce microbial growth in food products. Olive oil industry by-products, due to bioactive compounds with potential antimicrobial properties such as polyphenols, could be used in carcass treatment to enhance hygienic and quality traits. The assessment of the antimicrobial efficacy of bioactive molecules against pathogens should be determined with in vitro and in situ models since it is not possible to evaluate it directly on carcasses at the slaughterhouse. This study aimed to evaluate the effect of an olive mill wastewater polyphenolic extract against Salmonella enteritidis and Listeria monocytogenes, simulating carcass surfaces using bovine dermis samples that were experimentally contaminated with the selected pathogens. The minimum inhibitory concentration and minimum bactericidal concentration were first determined for S. enteritidis and L. monocytogenes. In situ bactericidal activity assessment was performed using 20 cm2 derma samples contaminated with 5 Log CFU/20 cm2 of S. enteritidis and L. monocytogenes in separate trials. Treatment with the polyphenolic extract was not effective for either microorganism. In order to establish the bacteriostatic activity of the polyphenolic extract, suspensions of about 2 Log CFU/20 cm2 of S. enteritidis and L. monocytogenes were used. Polyphenolic extract treatment was not effective against Salmonella, while for Listeria it allowed microbial growth to delay (around 1 Log CFU/cm2 difference at 3, 7, and 14 days between treated and control groups). Further investigations are needed to evaluate the application of polyphenolic compounds on carcass surfaces and their effects on sensory traits.

Consumption of raw or undercooked wild boar (WB) meat is considered an important risk factor for hepatitis E virus (HEV) infection in humans. The possibility of HEV contamination during the slaughtering practices may pose an additional risk. Based on these assumptions, we evaluated HEV contamination of WB meat hunted in Umbria (central Italy) during the 2022–2023 hunting season by real-time RT-PCR. Herein, we show that 10.8% of livers from slaughtered WB were positive for HEV RNA, thus providing an estimate of HEV infection in WB in the Umbria region. Then, by evaluating paired liver–muscle samples from both HEV-positive and HEV-negative animals, we found evidence of muscle HEV contamination in 33% and 14% of cases, respectively. This is the first report on the detection of HEV in WB meat in Umbria, an Italian region with diffuse WB hunting and consumption. The evidence of contamination provided by our study underscores the importance of adopting good hygienic practices in the processing stages of hunted WB carcasses to significantly reduce meat contamination and the risk posed for the final consumer.

A survey was conducted from 2018 to 2023 to assess the presence of Salmonella in 280 hunted wild boar (carcasses after evisceration and skinning, N = 226; liver, N = 258; and fecal samples, N = 174). The overall prevalence was 2.86% (confidence interval 95%, 1.45–5.45%) with five positive samples detected in carcasses, three in the liver, and one in a fecal sample. This prevalence was in line with those found in nearby areas denoting a low number of positive samples. Positive animals were over 24 months of age and weighed, before skinning, 59.00 ± 9.11 Kg and no difference was detected in microbial loads between samples positive and negative for Salmonella (aerobic colony count of 4.59 and 4.66 log CFU/400 cm2, and Enterobacteriaceae count of 2.89 and 2.73 log CFU/400 cm2 (mean values) in positive and negative subjects, respectively). Salmonella Stanleyville was the most frequently isolated serotype. A semiquantitative risk assessment was conducted for the first time in game meat considering two products, meat cuts intended for cooking and fermented dry sausages. Only proper cooking can reduce the risk of ingestion of Salmonella to the minimum for consumers, whereas ready-to-eat dry sausages constitute risk products in terms of foodborne Salmonellosis (risk score of 64 out of 100).

Despite the technologies applied to food production, microbial contamination and chemical deterioration are still matters of great concern. In order to limit these phenomena, new natural approaches should be applied. In this context, the present study aimed to assess the antioxidant and anti-Clostridial effects of two different polyphenolic extracts derived from olive mill vegetation water, one liquid (LE) and one encapsulated (EE). The extracts have been preliminary characterized using Liquid Chromatography Quadrupole Time-Of Flight spectrometry. The Oxygen Radical Absorbance Capacity method was used to determine the antioxidant capacity, registering a higher value for EE compared to that for LE (3256 ± 85 and 2446 ± 13 µgTE/g, respectively). The antibacterial activity against C. perfringens, C. botulinum and C. difficile was studied by the agar well diffusion method, MIC and MBC determination and a time-kill test. The results confirm that EE and LE are able to limit microbial growth, albeit with minor effects when the phenolic compounds are encapsulated. Further studies are needed to evaluate the possible application of these extracts in food systems.

Atherina boyeri is the primary source of fishing profit in Lake Trasimeno and a common host for Eustrongylides spp. larvae. The presence of Eustrongylides in fish is a public health concern, and effective risk management procedures are necessary to guarantee that infected products do not reach the market. Currently, in the European Union, there is no official sampling plan for fresh fish that defines sample size, inspection methods, and criteria for accepting or rejecting the product. An approach to Eustrongylides risk management is proposed in this study. A total of 270 batches of Atherina boyeri, each consisting of 29 specimens, were collected and examined visually in 3 years (2020-2023). The prevalence (P) of the parasite was 20% in 2020, and in the first months of 2021, it grew up to ⁓40%, then dropped to 12.50% in December 2021 and settled at 16% in February 2022. In January and February 2023, the P fell below 1%. The mean abundance was calculated and used to establish a threshold value to determine fish marketability. In 2020 and 2021, several batches were judged not marketable, and in some batches, a freezing treatment was implemented to assure the inactivation of the parasite. In the last months of 2022 and in January and February of 2023, the presence of parasites in captured fish was negligible, and this allowed the marketability of fish as fresh. The proposed sampling plan was effective in preventing the commercialization of potentially hazardous products.

Fish are good bio-indicators of the health status of the aquatic environment and can be used as biomarkers to assess the aquatic behavior of environmental pollutants, the exposure of aquatic organisms, and the health risk for consumers. Goldfish are a significant bioindicator in the Lake Trasimeno aquatic system (Umbria, Italy). This study aimed to characterize the health status and the chemical and biotic contamination of Lake Trasimeno to define its anthropogenic and natural pressures and the risk associated with consuming its fishery products. 114 determinations were performed on Carassius auratus samples from 2018 to 2020, and the occurrence of brominated flame retardants, non-dioxin-like polychlorinated biphenyls, heavy metals, and microplastics was analytically investigated. Dietary exposure assessment, risk characterization, and benefit-risk evaluation were performed for schoolchildren from 3 to 10 years old. Flame-retardants registered high levels of non-detects (99% for polybrominated diphenyl ether and 76% for hexabromocyclododecanes), while polychlorinated biphenyls were found in all samples with a maximum level of 56.3 ng/g. Traces of at least one heavy metal were found in all samples, though always below the regulatory limit. Microplastics were found with a 75% frequency of fish ingesting at least one particle. Dietary exposure and risk characterization reveal negligible contributions to the reference values of all contaminants, except for mercury, which reached up to 25% of admissible daily intake. The benefit-risk assessment highlighted that the benefits of freshwater fish intake outweigh the associated risks. The examination of goldfish as indicator fish reveals the quality of Lake Trasimeno's aquatic environment and the safety of its products.

A profile of the microbial safety and hygiene of cheese in central Italy was defined based on an analysis of 1373 cheeses sampled under the Italian National Control Plan for Food Safety spanning the years 2013 to 2020 and tested according to Commission Regulation (EC) No. 2073/2005 (as amended). A total of 97.4% of cheese samples were assessed as being satisfactory for food safety criteria and 80.5% for process hygiene criteria. Staphylococcal enterotoxin was found in 2/414 samples, while Salmonella spp. and Listeria monocytogenes were detected in 15 samples out of 373 and 437, respectively. Escherichia coli and coagulase-positive staphylococci counts were found unsatisfactory in 12/61 and 17/88 cheese samples, respectively. The impact of milking species, milk thermal treatment, and cheese hardness category was considered. A statistically significant association (p < 0.05) was found between milk thermal treatment and the prevalence of coagulase-positive staphylococci and Listeria monocytogenes and between hardness and unsatisfactory levels of Escherichia coli. The data depict a contained public health risk associated with these products and confirm, at the same time, the importance of strict compliance with good hygiene practices during milk and cheese production. These results can assist in bolstering risk analysis and providing insights for food safety decision making.

Yersinia enterocolitica represents one of the main foodborne pathogens in Europe and the evaluation of possible sources of contamination and its prevalence in food is of considerable interest for risk analysis approach. The results of the search for Yersinia enterocolitica in food samples taken in Umbria region (central Italy) were evaluated during the years 2015-2018. Different types of foods were considered, both ready-to-eat (meat products, dairy products, and raw vegetables) and meat preparations to be eaten after cooking. Samples were assayed by molecular screening for the species indicator gene ompF. Screening positives were subjected to isolation and characterization by searching for specific virulence marker genes, including the ail gene responsible for invasiveness and the ystB gene for the production of enterotoxin. The total prevalence of positive samples for Yersinia enterocolitica was 16.86% with a higher percentage of positive samples in meat preparations (19.35%), followed by ready-to-eat vegetables (11.76%). Poultry meat samples had a higher prevalence than pork and beef samples. Neither positive samples were found in meat products and dairy, nor seasonality in positivity was observed. All isolated strains of Yersinia enterocolitica were biotype 1A, with absence of the ail virulence gene but presence of ystB gene. Since the strains isolated from human patients appear to be primarily biotypes that possess the ail marker, future investigations would be needed regarding the real role of biotype 1A in human disease. In this context, attention should certainly be paid to ready-to-eat vegetables and to careful cooking of meat preparations.

Tyrosol (T) and hydroxytyrosol (HT) are phenyl alcohol polyphenols with well-recognized health-promoting properties. They are widely diffused in several vegetables, especially in olive products (leaves, fruits and oil). Therefore, they could be present in food produced from herbivorous animals such as in milk and cheese. In this study, an analytical method to determine T, HT and some of their phase II metabolites (sulphates and glucuronides) in cheese was developed and validated. Samples were extracted with an acidic mixture of MeOH/water 80/20 (v/v) and, after a low temperature clean-up, the extracts were evaporated and injected in a liquid-chromatography coupled with high resolution mass spectrometry (LC-Q-Orbitrap). A validation study demonstrated satisfactory method performance characteristics (selectivity, linearity, precision, recovery factors, detection and quantification limits). The developed protocol was then applied to analyze 36 Italian cheeses made from ewe, goat and cow milk. The sum of detected compounds (T, tyrosol sulfate, hydroxytyrosol-3-O-sulfate and hydroxytyrosol-4-O-sulfate) reached as high as 2300 µg kg−1 on a dry weight basis, although in about 45% of cow cheeses it did not exceed 50 µg kg−1. Ewe cheeses were significantly richer of polyphenols (sum) as well as HT sulfate metabolites than cow cheeses. In conclusion, results shows that cheese cannot be considered an important dietary source of these valuable compounds.

Hazelnut shells, the main waste deriving from hazelnut processing, represent an interesting source of active molecules useful in pharmaceutics, although they have not yet been examined in depth. A hydrosoluble extract (hazelnut shell extract, HSE) was prepared by the maceration method using a hydroalcoholic solution and used as the active ingredient of patches (prepared by casting method) consisting of composites of highly deacetylated chitosan and green clay. In vitro studies showed that the formulation containing HSE is able to stimulate keratinocyte growth, which is useful for healing purposes, and to inhibit the growth of S. aureus (Log CFU/mL 0.95 vs. 8.85 of the control after 48 h); this bacterium is often responsible for wound infections and is difficult to treat by conventional antibiotics due to its antibiotic resistance. The produced patches showed suitable tensile properties that are necessary to withstand mechanical stress during both the removal from the packaging and application. The obtained results suggest that the developed patch could be a suitable product to treat wounds.

In recent years, there has been a growing interest in the use of novel antimicrobial agents able to inhibit or kill food-borne bacteria or to interrupt the onset of food spoilage. Crocus sativus L. petals, typically considered as waste obtained from saffron spice production, could be a source of natural bioactive compounds to be used as food preservatives. The purpose of this work was to investigate the antibacterial properties of two hydroalcoholicsaffron petal extracts obtained by maceration (SPEA) and by ultrasonic bath (SPEB) methods. The main polyphenols identified in both extracts were gallic and chlorogenic acids, representing almost 70% of the phenolic fraction monitored. The antibacterial activity was studied by the agar well-diffusion method, against food-borne pathogenic and spoilage bacteria. Both extracts showed activity mainly against Gram-positive bacteria, in particular those belonging to the Clostridiaceae family (C. perfringens, C. botulinum and C. difficile), with inhibition zone diameters ranging from 13 to 18 mm. The antibacterial properties against Clostridia were further analyzed, determining MIC and MBC and performing a time-kill test. SPEA showed lower MIC/MBC values (250 mg/mL) compared to SPEB (500 mg/mL), suggesting that it could be more active against the assayed strains, probably because of its higher content of gallic acid. SPEA and SPEB, tested at a concentration of 1 × MIC, showed bactericidal activity against C. perfringens, C. botulinum and C. difficile and these results suggest that saffron petals could represent a valuable natural alternative source to conventional preservatives. Further investigations are needed to evaluate possible applications in the food industry.

Solutions of lactic acid 2% and aromatic vinegar were investigated for microbial load reduction on the surfaces of wild boar carcasses. The animals were hunted and processed according to production specifications to obtain the best hygiene for carcasses. The solutions were sprayed on carcass surfaces after skinning, and sites of 5 × 5 cm were sampled 2 h and 48 h post-treatment, with the carcasses under refrigeration conditions. The values of the microbial loads were lower for lactic-acid-treated sites, compared with control, after both 2 and 48 h. Nonetheless, the differences in the microbial loads were only higher than 1 Log/CFU 25 cm2 for the aerobic colony count. The aromatic vinegar resulted in lower values than in controls only after 48 h for the aerobic colony count, Staphylococcus count, and Lactobacillus count, with values always below 1 Log/CFU 25 cm2. The implementation of a lactic acid solution could represent a valuable strategy to reduce microbial growth on wild boar carcasses, thus becoming a relevant critical control point in this peculiar and niche meat production process.

The mincing process of raw meat favors microbial spoilage as well as chemical and enzymatic oxidation processes. In order to limit this degradative process, preservatives are routinely added to minced meat products. The role of olive mill wastewater polyphenolic extract as a replacement for synthetic preservatives in beef burger was assessed. The antioxidant capacity of the extract experimentally added to beef burger was evaluated using the oxygen radical absorbance capacity method (ORACFL) to assess the shelf-life, while the lipid oxidation was measured by thiobarbituric reactive substance (TBAR) determination. The antimicrobial activity was assayed by means of classical methods and predictive microbiology. The experimental addition of polyphenolic extract led to 62% lower lipid oxidation and 58% higher antioxidant capacity; it also successfully modulated spoilage microbial populations with an average growth reduction of 15% on day 7. Results indicate that olive mill wastewater polyphenolic extracts could be added to raw ground beef meat to act as natural antioxidants and to modulate microbial growth.

Aflatoxin M1 (AFM1) is a hepatocarcinogenic and genotoxic derivative of aflatoxin B1 excreted into milk after ingestion of feed contaminated by Aspergillus genus fungi. Because of the important role of dairy products, especially cow cheese, in the human diet, there is great concern about the presence of AFM1 in this food category. EC Regulation No. 1881/2006 establishes the importance of the enrichment factor (EF), an essential parameter that must be defined in order to evaluate the maximum level of the toxin in cheese aiming to ensure that cheese has been produced from compliant milk. The Italian Ministry of Health has established two provisional AFM1 EFs (5.5 and 3.0) to be applied to as many cheese categories (hard and soft), defined according to the moisture content on a fat free basis (MFFB) classification. Two experimental productions of Primosale and Fior di Latte cheese, both belonging to the soft cheese category, showed an EF of 4.1 and 2.9 respectively. Data in literature also suggest that the EF attribution based on the current categorization may need reconsideration.

Abstract Background The Mediterranean diet is considered one of the healthier food habits and olive oil is one of its key components. Olive oil polyphenols are known to induce beneficial effects in several pathological conditions, such as inflammatory bowel disease, and to contrast the proliferation of cancer cells or hypercholesterolemia. Polyphenols are also present in waste products derived from the olive industry: olive mill wastewaters (OMWW) are rich in polyphenols and there is an increasing interest in using OMWW in animal nutrition. OMWW are attributed with positive effects in promoting chicken performance and the quality of food-derived products. However, a tissue-specific transcriptome target analysis of chickens fed with OMWW has never been attempted. Results We explored the effect of dietary OMWW on the intestinal function in broilers. A morphological analysis of the jejunum revealed that OMWW reduced crypt depth, whereas no significant modifications were observed for villus height and the villus height/crypt depth ratio. An RNA Sequencing analysis was performed on isolated, intestinal, epithelial cells and 280 differentially expressed genes were found using a count-based approach. An enrichment analysis revealed that the majority of up regulated genes in the OMWW group were over-represented by the regulation of viral genome replication-related GO-Terms, whereas down regulated genes were mainly involved in cholesterol and lipid metabolism. Conclusions Our study showed how an industrial waste product can be recycled as a feed additive with a positive relapse. OMWW dietary supplementation can be a nutritional strategy to improve chicken performance and health, prevent intestinal damage, enhance innate immunity and regulate cholesterol metabolism and fat deposition.

Salmonella in pork is still a relevant safety issue in the EU, and specific regulations are in force to control this hazard in the meat chain, in a from farm to fork perspective. In Italy, the control is mainly based on official sampling at the slaughterhouse level. The prevalence of Salmonella, and isolated serovars, was investigated during a three-year survey in small and medium slaughterhouses in central Italy. A total of 400 pig carcasses samples were collected by official authorities during the observation period. Data were also analyzed according to the year and season of sampling. The overall Salmonella prevalence in the five selected abattoirs was 13%, with no differences due to the slaughterhouses size and seasons of sampling. An increasing trend in Salmonella prevalence was registered over the years. The main serovars detected were Salmonella enterica 4,[5],12:i:- and Derby. The data emphasized that the number of contaminated carcasses is relatively high with respect to the level set by EU legislation, and equally distributed in the area, and therefore, appropriate monitoring and control strategies also need to be developed at the farm level.

Aflatoxin food contamination represents a rising global issue that will continue to increase due to climate change. Aflatoxin M1 (AFM1) is of high concern for the whole dairy industry. In light of AFM1′s harmful potential, a human health exposure assessment and risk characterization were performed for all age populations of central Italy with regard to milk and cheese consumption by means of the margin of exposure (MOE). In total, 16,934 cow and ewe’s milk samples were collected from 2014 to 2020 and analyzed by an enzyme-linked immunosorbent assay (ELISA) screening method, confirmed by high-performance liquid chromatography with a fluorescence detector (HPLC-FLD). The average concentration of AFM1 in cow’s milk ranged from 0.009 to 0.015 µg/kg, while in ewe’s milk, the average concentration ranged from 0.009 to 0.013 µg/kg. The average amount of AFM1 exposure ranged from 0.00005 to 0.00195 g/kg bw/day, with the main contributor represented by drinking milk, followed by the consumption of soft cheeses. A high level of public health concern related to the youngest consumers has arisen from risk characterizations highlighting the need for constant monitoring of AFM1′s occurrence in milk by inspection authorities, alongside regular updates with regard to exposure assessments.

The prevalence of Coxiella burnetii, the causative agent of Q fever, in cattle and sheep raw milk farms was determined in Central Italy, an area in which dairy production plays an important economic role. Milk samples (n. 189), collected from 66 dairy farms in 2012–2013, were tested by a commercial real-time PCR assay. Seventeen dairy farms had at least one positive milk sample; percent positive was higher for cattle (50%) than sheep (21%) farms. Concerning milk, 15% of samples tested overall gave a positive result, with the highest percentage of positivity observed for bovine milk compared with sheep milk (41% and 12%, respectively). In the only bovine farm repeatedly sampled during the study, C. burnetii contamination was persistently found for almost a year. The prevalence calculated for the sheep farms showed a discontinuous trend with a maximum peak in February. The results obtained underline the widespread presence of the pathogen in the considered geographical area, giving new epidemiological information. Since the milk route of elimination is a potential vehicle of infection for farmers, veterinarians and for dairy stakeholders in general, BTM screening by real-time PCR can be applied as a useful surveillance tool both for the identification of infected flocks and implementation of control programmes.

The present study evaluated the safety, nutritional and sensory properties of fish pâtés made from smoked tench (Tinca tinca) pulp. Two formulations of tench pâté were produced, one of which included olive oil and the other contained mascarpone cheese. The prepared pâté jars were thermally treated according to the method applied in the canning industry. The inactivation of Clostridium botulinum during thermal treatment was determined through a challenge test study, demonstrating the complete depletion of targeted bacteria. Tench pâtés showed high nutritional properties, especially the formulation with olive oil, which was characterised by lower contents of cholesterol and saturated fatty acids and a high level of monounsaturated fatty acids. The two experimental formulations possessed a specific sensory profile, due to the ingredients incorporated into the products. Consumers’ evaluation established differences in the acceptance of the two products: the formulation with added olive oil was more appreciated by consumers, who displayed a higher purchase intent for this product. The study suggests that minced smoked tench is not only a promising ingredient for pâté production but that it also represents a value-added product able to contribute to freshwater food consumption.

The aim of the study was to define the chemical characteristics, antioxidant capacity, oxidative status, sensory properties, and the presence of polyphenols in ovine cheese obtained after dietary administration of spray-dried olive mill wastewater (SDP). SDP is a waste from olive oil production rich in bioactive molecules obtained by further processing the olive mill wastewater through a spray-drying system. Thirty-six sheep were randomly assigned to two experimental groups that received a standard diet based on hay and concentrate. The concentrate fed to the SDP group was supplemented with SDP at a rate 25 g/kg (as fed). The trial lasted 9 weeks. Milk from the two treatment groups was separately collected and used for manufacturing cheese. Cheese quality parameters and proximate composition were not affected by the dietary treatment, whereas the antioxidant status and oxidative stability of cheese were positively affected. Polyphenol analyses in cheese were performed through liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The concentration of hydroxytyrosol and tyrosol, and their sulphate metabolites, were higher in cheese from supplemented sheep. These findings suggest that polyphenol metabolites can play a major role in the beneficial effects observed in food produced from sheep fed SDP.

Recently, particular attention has been addressed to the control of Listeria monocytogenes in ready-to-eat meat products, such as fermented salami, as a consequence of several listeriosis outbreaks associated with the consumption of these types of products. A short-ripened spreadable salami, typically produced in the Umbria region (Central Italy), was challenged with L. monocytogenes aiming to evaluate the pathogen’s growth dynamics and to define its growth potential during processing and storage time. The pathogen counts were stable in the inoculum level (2 Log CFU/g) during the production process and up to 30 days of storage time, decreasing thereafter. The growth potentials registered for process phase and storage time were 0.40 and −1.28, showing that the application of the hurdles technology principle successfully creates an unfavorable environment for L. monocytogenes growth.

The presence of viable Toxoplasma gondii was investigated in artisanal cheeses made from milk of naturally infected ewes. Ewe milk was analyzed beforehand for the presence and vitality of T. gondii by loop-mediated isothermal amplification (LAMP) and reverse-transcriptase PCR (RT-PCR), respectively. Cheeses were prepared from raw milk following a traditional cheesemaking process. The cheese obtained from T. gondii-positive milk was analyzed by LAMP to detect Toxoplasma DNA-positive samples. RT-PCR was then carried out to assess the viability of the parasites in T. gondii-positive milk samples and fresh cheese, after 5 and 15 days of ripening. Physical-chemical parameters of cheeses were also investigated. All cheese samples derived from T. gondii-positive milk were positive according to LAMP, at both 5 and 15 days of ripening, while none of the samples were positive according to RT-PCR. Thus, while the presence of the parasite was demonstrated by the detection of specific DNA, the absence of detectable T. gondii RNA supports the hypothesis that changes in the chemical and physical characteristics occurring during the cheesemaking process and ripening period, could be sufficient to inactivate viable T. gondii in milk, minimizing the risk of human infection through consumption of raw sheep milk cheese.

Considering that many plant-derived substances show antioxidant and antimicrobial properties, natural antioxidant administered through feed in livestock animals could increase the shelf life of meat and meat products. The aim of this work was to study the effect of olive oil by-products on chicken meat lipid and protein oxidation and oxidative stability during storage. Two hundred and ninety-seven 22-day-old fast growing (Ross 308) female chicks were randomly assigned to three experimental grower-finisher diets: i) a basal control diet (CTR), ii) CTR diet supplemented with a low dosage (4.8%) of olive mill wastewater extract (L-OW) and iii) CTR diet supplemented with a high dosage (9.9%) of olive mill wastewater extract (H-OW). Breast meat of animals belonging to each experimental group was sliced, overwrapped with oxygen-permeable packaging and analysed at three different storage times (zero, three and seven days). At the three sampling times considered, for all samples, colour coordinates (a*), saturation index, Hue angle, peroxide value, thiobarbituric reactive substance, carbonyl assay and the oxygen radical absorbance capacity determinations were performed. No differences in colour were detected among the groups in all the sampling times considered. In conclusion, the supplementation of chicken diet with olive mill wastewater extract (OW) affected oxidation of meat, retarding lipid and protein oxidation and improving antioxidant activity during storage.

Eustrongylides spp. is considered a freshwater fish zoonotic nematode. In the present study, the prevalence of Eustrongylides spp. in six edible fish (European perch - Perca fluviatilis, goldfish - Carassius auratus, largemouth black bass - Micropterus salmoides, tench- Tinca tinca, carp - Cyprinus carpio and sand smelt - Atherina boyeri) of Trasimeno lake was surveyed. The investigations were conducted from October 2014 to September 2015 and 384 specimens per species for each season were caught in Trasimeno lake and examined for the presence of larvae in the abdominal cavity and muscle. The presence of nematodes in the abdominal cavity and musculature was revealed in three fish species. The prevalence of Eustrongylides spp. infection was 6.84, 1.89 and 0.13% in perch, largemouth black bass and sand smelt, respectively. The number of parasites per fish was only one in largemouth black bass and sand smelt and ranged from one up to three in perch. This study states that the European perch, largemouth black bass and sand smelt of Trasimeno lake are infected with zoonotic parasites; therefore, food business operators have to take appropriate measures to guarantee the health of consumers.

An experimental study for the evaluation of Listeria monocytogenes inactivation during a hot smoking process in tench was performed using Listeria innocua strains. Furthermore, the survival of L. monocytogenes in smoked tench was determined after post-processing in contaminated samples, evaluating the growth potential during storage. L. innocua was not detected after the smoking process. In the challenge test, the growth potential of L. monocytogenes was 5.68 log colony forming unit g−1. The results showed that hot smoking at an inner temperature around 72°C is able to eliminate the microorganism. Nevertheless, the product is able to support the growth of the pathogen if post-process contamination occurs, as the food is suitable for Listeria multiplication. Product recontamination should be prevented by means of appropriate application of hygiene measures.

Olive mill wastewater polyphenol extract was tested for antimicrobial activity against 64 strains of Pseudomonas fluorescens responsible for mozzarella discolouration. The extract showed a minimum inhibitory concentration (MIC)50 value of 5 mg/mL and a MIC90 value of 7 mg/mL. The MBC50 and MBC90 values corresponded to 6 and 8 mg/mL, respectively. The MIC concentration (7 mg/mL) was demonstrated to have a bacteriostatic effect while maintaining the bacterial concentration on the levels of the inoculum for 48 hours. The 3/2 MIC concentration was responsible for four logs CFU/mL depletion in colony count after 24 h. As the extract concentration decreased from MIC value, no inhibitory effects were recorded.

In the present study, a microbiological challenge test in artificially contaminated raw milk Pecorino Umbro cheese during cheese-making was carried out. Raw ewe milk was contaminated by a suspension of particular Listeria monocytogenes strains. The number of L. monocytogenes and L. monocytogenes dynamic growth were evaluated during cheese-making and storage. A significant decrease of the viable count of L. monocytogenes was observed during ripening and L. monocytogenes viable count was below the limit of quantification during storage. The results show that the product is unable to support the growth of the pathogen.

Hypoallergenic properties of ass’s milk protein fractions have been recently con- firmed, allowing ass’s milk to be considered as a valid substitute of the available hypoallergenic infant formulas. The objective of this study was to give a further contribution to the knowledge of ass’s milk safety and quality characteristics. A new procedure has been developed with a cytospin centrifuge in differential counts of milk somatic cells. Somatic cells count (SCC), differential somatic cells count (DCC) and cultural examinations have been carried out in 62 milk samples collected from 11 asses at three different stages of lactation. Four major cells populations had been identified in ass’s milk too: lymphocytes (Ly), monocytes/macrophages (MA), polymorphonuclear neutrophils (PMNL), and epithelial cells (CE). The patterns of these cells have been discussed in comparison with cells found in dairy cows and ewes milk. In conclusion, a reproducible standard procedure has been developed to determine cell count of ass’s milk.