Search

This work investigated bacteriophage induced starter failures in artisanal buffalo Mozzarella production plants in Southern Italy. Two hundred and ten samples of whey starter cultures were screened for bacteriophage infection. Multiplex polymerase chain reaction (PCR) revealed phage infection in 28.56% of samples, all showing acidification problems during cheese making. Based on DNA sequences, bacteriophages for Lactococcus lactis (L. lactis), Lactobacillus delbruekii (L. delbruekii) and Streptococcus thermophilus (S. thermophilus) were detected. Two phages active against L. lactis, фApr-1 and фApr-2, were isolated and characterised. The genomes, approximately 31.4 kb and 31 kb for фApr-1 and фApr-2 respectively, consisted of double-stranded linear DNA with pac-type system. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed one major structural protein of approximately 32.5 kDa and several minor proteins. This is the first report of phage isolation in buffalo milk and of the use of multiplex PCR to screen and study the diversity of phages against Lactic Acid Bacteria (LAB) strains in artisanal Water Buffalo Mozzarella starters.

The European Commission (EU) laid down the general principles and requirements of food law where it had changed the approach to food safety through the integrated control of the food chain. Hazard characterisation’ is the quantitative and/or qualitative evaluation of the adverse effects that may results from the ingestion of chemical, microbiological and physical agents presents in foods. This chapter provides an assessment of the risk associated with the consumption of different cheeses for the possible presence of certain toxins. FAO (1978) has provided a classical definition of cheese that is accepted internationally. Staphylococcal intoxication is a common cause of bacterial foodborne outbreaks, linked to the ability of Staphylococcus aureus to produce thermostable staphylococcal enterotoxins (SEs). In the dairy chain, contesting the hazard identification is linked to the microbiological quality of raw milk, the cheesemaking process including raw and/or pasteurisation of the milk, maturation of the pressed curd, and handling at home. Approaches to Assess the Risks/Modelling of Microbial Growth and Toxin Production | Request PDF. Available from: https://www.researchgate.net/publication/312275438_Approaches_to_Assess_the_RisksModelling_of_Microbial_Growth_and_Toxin_Production [accessed Jan 19 2018].

To assess sea bream (Sparus aurata) thawing, two ultrasonographic (US) protocols were used. The first protocol was used on 15 subjects at three different times immediately after capture, after the first thaw, and after the second thaw. A general-purpose device equipped with a linear high-frequency probe was used. On the B-mode-Real Time images, quantitative analysis of the epiaxial muscle gray levels was made. For the second protocol, a quantitative US (QUS) device was used on three groups of fish samples (fresh, thawed once, and thawed twice), each composed of five subjects. Speed of sound, bone ultrasound attenuation, bone mineral density, and quantitative ultrasound index were measured. Data were statistically compared using ANOVA (P < 0.05). Gray levels differed significantly among the three control times. QUS data differed significantly between the fresh and thawed groups. US and QUS appear to be promising techniques for assessing fish thawing.

The content of benzo[a]pyrene (BaP), a polycyclic aromatic hydrocarbon, was determined by HPLC/FL in ???mozzarella di bufala campana??? cheese, a stretched cooked cheese, either experimentally smoked according to traditional procedures, using straw, cardboard, and wood shavings or aromatized with smoke flavoring. The BaP residues, researched also in cheese samples sold at retail, were detected in the rind, in the core, and in the slice (outer and inner parts).In the cheeses experimentally smoked with straw and cardboard the BaP levels, ranging from 0.38 to 2.12 íg kg-1 and from 0.46 to 2.40 íg kg-1, respectively, were statistically higher than those of the cheeses smoked with wood shavings and aromatized with liquid smoke (from 0.19 to 0.80 íg kg-1 and from 0.18 to 0.50 íg kg-1, respectively). However the cheeses treated with liquid smoke flavor showed a BaP content exceeding the level allowed by the European Union .

Consumer is very careful about healthiness; in this context nutritionists often highlight the importance of fish for human nutrition because of their protein and fatty acid composition. In order to stimulate utilisation and consumption of fish species by unusual target groups such as children, the aim of this research was to formulate and to evaluate shelf-life and nutritional values of fish preparations stored in modified atmosphere packaging (MAP). Fish species used for trail were Trachurus trachurus and Oncorhynchus mykiss fished and farmed in Basilicata region respectively. Fish burgers were made with different ingredients of plant and animal origin and packed in air (control) and in MAP and stored at refrigeration atemperature. Sensory, physicalchemical analysis as pH, aw, total volatile nitrogen (TVN), trimetilammine (TMA), thiobarbituric acid (TBA), free fatty acids (FFA) and microbiological analysis like aerobic plate count, Enterobacteriaceae, Escherichia coli, Pseudomonas spp., sulphite-reducing clostridia, Staphylococci, Salmonella spp. and Listeria monocytogenes were performed at intervals of 0°, 1°, 2°, 5°, 8°, 15°, 22°, day from production. Results showed that fish burgers stored in MAP had a longer shelf-life; protein degradation indexes and spoilage bacterial species showed lower values in the samples packaged in MAP compared with the control. The formulation of the fish burger meets the approval of the target consumers. The mixing of natural ingredients has made possible both the enhancement of the organoleptic characteristics with an excellent balance of nutritional values. The diversification of fish preparations, besides enhancing the fish production of marginal areas would add value to a product with potential and remarkable profit margins.

Pre-slaughter stress can result in variations in the glycogen storage and metabolic changes of muscle, responsible for quality poultry meat. Aim of this study was to investigate, as pre-slaughter stress markers and quality meat, physicochemical (pH), biochemical (muscle glycogen content), and chemical (super oxides free radicals) parameters. The carcass quality, as incidence of individual carcass defects, was also evaluated. Twenty broilers were processed with two different electrical stunning: high (250 Hz; 640 mA; 60V) (Lot C or control) and low (150 Hz; 360 mA; 60 V) (Lot A) frequency and intensity, using sinusoidal alternating current. As preliminary results, the use of low frequency and intensity induced faster pH decline post mortem and adequate acidification of pH at 3 hours (6.49 Lot C; 6.37 Lot A), better muscle glycogen reserve (0.770 μL/50 mL Lot C; 1.497 μL/50mL Lot A), and lightly more rapid muscle oxidation (IDF: 0.109 Lot C; 0.122 Lot A), (FOX: 0.131 MeqO2/kg Lot C; 0.140 MeqO2/kg Lot A). The incidence of individual carcass defects sufficient to cause downgrading or rejection, both in Lot C and Lot A, was generally low. In a multidisciplinary approach, to assess animal welfare and quality poultry meat, additional and feasible parameters should be implemented. Monitoring of pH, muscle glycogen reserve and superoxide free radical production measurements might be markers easier to use, routinely, in practice at abattoir. Further studies are needed to evaluate the usefulness of these parameters.

This study was designed to investigate physicochemical (pH, peroxides) and histological parameters (glycogen reserve, muscle damages), as pre-slaughter stress markers and quality meat evaluators. Ross commercial broilers was processed, either without stunning (NS Lot), or by combining two current levels of 200 mA, 67 V (HV Lot), and 200 mA, 53 V (MV Lot); with two frequencies of 1000 Hz and 800 Hz, using sinusoidal alternating current. The use of high frequency (800 and 1000 Hz) induced the fastest pH decline, already at 3 h postmortem, in Pectoralis major and Quadriceps femoris of MV and HV Lot carcasses (P < 0.05). Moreover HV carcasses showed a lesser production of superoxide free radicals than the NS Lot and MV Lot carcasses (P < 0.05). Changes in the glycogen reserve and the histological muscle damages did not show significant differences in the analysed Lots. The incidence of individual carcass defects, sufficient to cause downgrading or rejection was generally low in each Lot. To assess animal welfare and quality poultry meat the pH monitoring and measurement of superoxide radical production, as additional and feasible parameters, might be markers easier to use in practice at abattoir.

To assess the potential impact of the industrial activity on food safety and risk for consumers, the aim of the study was to evaluate the levels of 14 polycyclic aromatic hydrocarbons (PAH) in 69 samples of wild and farm Mytilus galloprovincialis, collected in sites of coast of Gulf of Naples, Tyrrhenian Sea. All hydrocarbons were found in samples. Higher levels of pyrolytic PAHs were in wild than in farm mussels. Benzo(a)pyrene exceeded the Regulation (EC) n.835/11 levels of 1 μg/kg in 15 samples (71.42%) of wild and 25 samples (65.79%) of farm mussels. System of sum of 4 hydrocarbons exceeded the law level in 15 samples (71.42%) of wild and 21 samples (55.26%) of farm mussels. Wild mussel levels showed a potential impact of pyrolytic sources of PAH on food safety. Occurrence of carcinogenic PAHs should be a cause for concern, in areas where the mussels are being farmed for human consumption.

Animal killing for food production and the related operations are events that may induce pain, stress, fear and other forms of suffering to the animals. To face this problem and guarantee the animal welfare, the EU has adopted the Regulation (EC) N. 1099/2009 on the protection of animals at the time of killing. Electrical water bath stunning is one of the methods used in commercial slaughterhouses to protect poultry welfare. In particular, this method induces unconsciousness into the birds due to run of electrical current through the head and body. The aim of the present work was to find an optimal setting of electrical parameters to obtain an effective water bath stunning in a commercial poultry slaughterhouse. Moreover, the influence of the tested electrical parameters on meat quality was evaluated. All the experiments confirmed that high stunning frequencies induce a lower occurrence of lesions on carcasses but, on the other hand, require greater current intensities to be effective. A frequency of 750 Hz and an average current intensity of 200 mA for each bird in the water bath resulted as the best combination of electrical parameters to obtain a proper stunning without any consequence on the meat quality.

Nitrate and nitrite concentrations in foods have aroused considerable interest because of their possible toxicity to humans, especially younger children. Since dietary exposure to these compounds includes sources other than vegetables, 104 infant foods consisting of animal, plant and mixed origin and available on sale to the public were examined using the spectrophotometric AOAC method to assess whether during the weaning period the use of commercial follow-on formulas could be a cause of concern for exceeding the ADIs set at international level. Nitrate values (mg kg−1) ranged between 0.35 and 131.68, nitrite between 1.12 and 80.22. The highest mean values were found in foods of plant origin (45.5) for nitrate and in foods of mixed origin (12.48) for nitrite. Nitrate contents never exceeded the level of 200 mg kg−1 set by EC Regulation 1881/2006 whereas the ingestion of most of the samples would have been the reason for exceeding the ADI set for nitrites.

To assure food safety in poultry meat the European Regulation does not authorize any decontamination treatment. Ozone has a strong oxidizing nature that makes it a useful tool for the inactivation of microorganisms. Aim of this study was to evaluate the effects of an experimental ozone gaseous treatment and production of the biogenic amines putrescine and cadaverine, as freshness index, during the storage of chilled poultry carcasses. Amines were extracted with perchloric acid, derivative with dansyl chloride, separated using a reversed- phase high-performance liquid chromatographic method, and detected by fluorescence. The results showed a reduction of microbial contamination as effect of the experimental ozone treatment of carcasses. In simply chilled poultry meat (Lot C control) a significant increases of putrescine and cadaverine at 15th days of storage. At 20t day higher levels of putrescine (53,63 mg/kg) and cadaverine (175,20 mg/kg) occurred in Lot C than in treated poultry meat of Lot A. Ozone decontamination resulted in lower levels of putrescine (32,37 mg/kg) and cadaverine (132,30 mg/kg), and in Lot A the shelf life was 6 days longer than in Lot C. If authorized, an ozone treatment during the storage of chilled poultry meat can induce a reduction of microbial contamination. Putrescine and cadaverine levels appeared to be useful to control the effectiveness of the ozone treatment on meat quality, and may be useful as quality index to highlight the loss of poultry meat freshness, before sensorial meat changes during storage of chilled poultry meat.

Functional genomics approaches enable us to investigate the biochemical, cellular, and physiological properties of each gene product and are nowadays applied to enhance food safety by understanding microbial stress responses in food and host-pathogen interactions. Listeria monocytogenes is a food-borne pathogen that causes listeriosis and is difficult to eliminate this pathogen since it can survive under multiple stress conditions such as low pH and low temperature. Detailed studies are needed to determine its mode of action and to understand the mechanisms that protect the pathogen when it is subjected to stress. In this study, deletion mutants of phosphotransferase transport system genes (PTS) and adenosine triphosphate(ATP)-binding cassette transporters (ABC) of Listeria monocytogenes F2365 were created using molecular techniques. These mutants and the wild-type were tested under different stress conditions, such as in solutions with different NaCl concentration, pH value and for nisin resistance. Results demonstrate that the behaviour of these deletion mutants is different from the wild type. In particular, deleted genes may be involved in L. monocytogenes resistance to nisin and to acid and salt concentrations. Functional genomics research on L. monocytogenes allows a better understanding of the genes related to stress responses and this knowledge may help in intervention strategies to control this food-borne pathogen. Furthermore, specific gene markers can be used to identify and subtype L. monocytogenes. Thus, future development of this study will focus on additional functional analyses of important stress response-related genes, as well as on methods for rapid and sensitive detection of L. monocytogenes such as using DNA microarrays.

The aim of this study was to evaluate the behavior of biogenic amines (BAs), especially histamine (HIS), and its correlation with pH, water activity (Aw), sodium chloride (NaCl), and microbiological parameters in innovative bluefin tuna (Thunnus thynnus) – raw, salted, seasoned and cooked products. The sensory analysis showed that this seafood typology, especially the pressed and cooked products, could be accepted willingly by consumer. The results showed amine profile trends that are similar to those observed during ripening and seasoning of pig meat products; HIS levels were found to be lower than the limits set by EU legislation in all products and during the whole storage period. To ensure the safety of the analyzed products, despite using raw materials of excellent quality, it is important to select process parameters that reduce the BA production.

Species belonging to the genus Thunnus are pelagic predator fishes, commonly known as tuna. The species within this genus are of commercial value, and six of them are considered the most valued in world trade (D.M., MIPAAF, 31 Gennaio 2008). Thunnus species originate from a variety of geographic areas, and for this reason the different species can be characterized by the presence of different biological contaminants and sensory characteristics. The species Thunnus thynnus has a higher quality and commercial value due to its excellent organoleptic features. Tuna species are usually consumed as fillets or processed products. The loss of the external anatomical and morphological features makes the authentication of a fish species difficult or impossible and enables fraudulent substitutions (Marko et al., 2004). Species substitution is very common in fish products, due to the profits resulting from the use of less expensive species. For species of tuna, substitutions have both commercial and health implications (Agusa et al., 2005; Besada et al., 2006; Storelli et al., 2010), thus, analytical techniques to differentiate fish species are essential. The development of suitable analytical methods for fish species identification in prepared and transformed fish products is of great interest to enforcement agencies involved with labelling regulations and the authentication of fish in various products to prevent the substitution of fish species (Mackie et al., 2000; Meyer et al., 1995). Several biochemical techniques enable the study and identification of fillet or minced fish species. Among these methods, isoelectric focusing (IEF) (Etienne et al., 2000; Rehbein et al., 2000; Renon et al., 2001;), capillary zone electrophoresis (Acuna et al., 2008), and amplification of selected DNA sequences by the polymerase chain reaction (PCR) have been used for the identification of certain groups of fish species (Espineira et al., 2008; Hubalkova et al., 2008; Pepe et al., 2005, 2007; Trotta et al., 2005). Presently, PCR is the most frequently used technique, as DNA is heat-stable and resistant to heat treatments that may be applied to the tuna during processing. However, obtaining an accurate species identification is very difficult if the species show a high degree of homology as Thunnus does (Chow & Kishino, 1995; Lopez & Pardo, 2005; Michelini et al., 2007; Pardo

The aim of this study was to evaluate the production of the vasoactive amines, histamine and tyramine, and of other biogenic amines (putrescine, cadaverine, spermidine, and spermine) during the ripening of pecorino Carmasciano cheese, a traditional Italian cheese produced with raw sheep milk. Vasoactive amines, which may pose health risks for consumers, showed relatively low levels near the end of Carmasciano ripening (136.41 mg/kg tyramine and 65.5 mg/kg histamine). The other biogenic amines were also detected and showed increasing levels with time. Results demonstrated that the concentrations of the vasoactive amines were always below the limits established for other foods. However, the data concerning raw materials and the increasing trend of certain biogenic amines highlight the need to control indigenous bacterial populations responsible for amine production, including the implementation of Good Manufacturing Practices and adequate training of staff.

Campylobacter is a major foodborne pathogen responsible for acute gastroenteritis characterized by diarrhea that is sometimes bloody, fever, cramps, and vomiting. Campylobacter species are carried in the intestinal tracts of mammals and birds, and sources of human infection include raw milk, contaminated water, direct contact with pets, and foods, particularly poultry. Campylobacter jejuni and C. coli are the species that account for the majority of human infections. The aim of this work was to determine the prevalence of Campylobacter in 190 poultry carcasses sampled at slaughter and to use a multiplex PCR assay to determine if the isolates were C. jejuni or C. coli. C. coli was not isolated, while C. jejuni was recovered from 52 (37.1%) of 140 carcasses for which pools of four sampling sites (neck, cloaca, breast, and back) were examined. In the remaining 50 carcasses, the four sites were analyzed separately, and C. jejuni was recovered from the samples in the following order: neck (n = 20), cloaca (n = 16), breast (n = 14), and back (n = 11). The results are in agreement with those of other studies, which showed that C. jejuni is more commonly associated with poultry than is C. coli. Control strategies for Campylobacter should include interventions to eliminate C. jejuni in poultry at various stages of production and processing, including at slaughter.

The increasing amount of farmed fish cannot be easily absorbed by the market as only fresh fish. The production and promotion of value-added fresh and processed fish products, which could fulfil consumers' present demands, may represent a solution to this problem. The aim of this paper is to review some of the most recent technologies, such as surface decontamination, use of "natural" additives and compounds, active packaging, used or experimented with to prolong shelf life, while ensuring the safety of fresh fish and fishery products.

Natural water-buffalo whey starters are used in the manufacture of Mozzarella cheese in Southern Italy. Microscopic examination of 12 commercial whey starters revealed high concentrations of lactic acid bacteria, in particular lactobacilli, containing inclusion bodies. Differential staining techniques revealed that the inclusion bodies contained high concentrations of polyphosphate (polyP). Because of the potential role of polyP in intracellular pH control, the presence of this polymer in starter bacteria may be an environmental adaptation to the typical high acidity storage conditions of natural starters.

The distribution of ivermectin in buffalo plasma and milk after administration of a single subcutaneous dose (0.2 mg kg(-)(1) b.w.) was studied. Ivermectin reached the maximal concentration in plasma (28.5 +/- 1.7 ng mL(-)(1)) and milk (23.6 +/- 2.6 ng mL(-)(1)) after 2.4 +/- 0.32 and 2.8 +/- 0.44 days, respectively. The drug showed a parallel disposition in milk and plasma, with a ratio of 1.12 +/- 0.16. Ivermectin concentrations were detected in mozzarella cheese obtained from milk collected on days 1, 3, 4, and 20 following administration. The highest values (81.4 +/- 3.26 ng g(-)(1)) were found in the cheese produced on day 3 and were 4-fold higher than those present in the milk.