High pressure processing to control Salmonella in raw pet food without compromising the freshness appearance: The impact of acidulation and frozen storage.

The trend of feeding dogs and cats with raw pet food claiming health benefits poses health concerns due to the occurrence of pathogenic bacteria. High pressure processing (HPP) allows the non-thermal inactivation of microorganisms, preserving the nutritional characteristics with minimal impact on organoleptic traits of food. The present study aimed to evaluate and model the effect of HPP application (450-750 MPa for 0-7 min) on the inactivation of Salmonella, endogenous microbiota and colour of raw pet food formulated with different concentrations of lactic acid (0-7.

Enhanced high hydrostatic pressure lethality in acidulated raw pet food formulations was pathogen species and strain dependent.

Feeding dogs and cats with raw meat-based pet food is taking relevance in the recent years. The high a of these products together with the no cooking before its consumption by the animal pose a risk due to the potential occurrence and growth of foodborne pathogens. High pressure processing (HPP) is a non-thermal emerging technology that can be used as a lethality treatment to inactivate microorganisms with a minimum impact on the sensory and nutritional traits of the product.

Risk management tool to define a corrective storage to enhance Salmonella inactivation in dry fermented sausages.

The resistance of Salmonella to the harsh conditions occurring in shelf-stable dry fermented sausages (DFS) poses a food safety challenge for producers. The present study aimed to model the behaviour of Salmonella in acid (with starter culture) and low-acid (without starter culture) DFS as a function of a and storage temperature in order to build a decision supporting tool supporting the design of a corrective storage strategy to enhance the safety of DFS. Salmonella spp.

Modelling the piezo-protection effect exerted by lactate on the high pressure resistance of Listeria monocytogenes in cooked ham.

Food safety is often based on the application of several preservative (hurdle) factors whose combination must be smartly selected. The aim of the present study was to evaluate the effect of lactate and diacetate on the high pressure processing (HPP) inactivation of three L. monocytogenes strains (CTC1011, CTC1034 and Scott A) in sliced cooked ham.

Modeling and designing a Listeria monocytogenes control strategy for dry-cured ham taking advantage of water activity and storage temperature.

Dry-cured ham is a shelf-stable product that can be contaminated with Listeria monocytogenes due to post-processing operations, compromising the compliance of zero tolerance policies (e.g. US Listeria rule).

Domestic refrigerator temperatures in Spain: Assessment of its impact on the safety and shelf-life of cooked meat products.

Temperature is one of the main factors governing the growth of microorganisms. The aim of the present study was to provide temperature conditions representative of the food products stored in domestic refrigerators and to assess the impact of the temperature (fluctuation) on the shelf-life of refrigerated cooked meat products, from the safety and the spoilage point of view. The analysis of the time-temperature profiles recorded from 160 domestic refrigerators of households from small (28%) and large (72%) municipalities in Catalonia (Spain) showed that the 24 h-mean temperature could be described by a normal distribution (mean = 5.

Assessment of the bioprotective potential of lactic acid bacteria against Listeria monocytogenes on vacuum-packed cold-smoked salmon stored at 8 °C.

Smoked salmon is a highly appreciated delicatessen product. Nevertheless, this ready-to-eat (RTE) product is considered at risk for Listeria monocytogenes, due to both the prevalence and growth potential of this bacteria on the product. Biopreservation may be considered a mild and natural effective strategy for minimizing this risk.

New insights on Listeria monocytogenes growth in pressurised cooked ham: A piezo-stimulation effect enhanced by organic acids during storage.

The aim of the present study was to understand growth and survival responses of Listeria monocytogenes during the storage of high pressure processed (HPP) cooked ham formulated with organic acids to inhibit growth of the pathogen. Cooked ham batches were manufactured without organic acids (control), with potassium lactate (2.8% or 4%) or with potassium lactate and sodium diacetate (2.

Diversity and distribution of Listeria monocytogenes in meat processing plants.

Listeria monocytogenes is a major concern for the meat processing industry because many listeriosis outbreaks have been linked to meat product consumption. The aim of this study was to elucidate L. monocytogenes diversity and distribution across different Spanish meat processing plants.

The potential probiotic Lactobacillus rhamnosus CTC1679 survives the passage through the gastrointestinal tract and its use as starter culture results in safe nutritionally enhanced fermented sausages.

The human-derived potential probiotic strain Lactobacillus rhamnosus CTC1679 was used as a starter culture in reduced fat and sodium low-acid fermented sausages (fuets) to assess its ability to survive through the gastrointestinal tract (GIT) in a human intervention study consisting of 5 healthy volunteers who consumed 25 g fuet a day for 21 days. Faecal samples were analysed during and after consumption. L.

Characterization of lactic acid bacteria isolated from infant faeces as potential probiotic starter cultures for fermented sausages.

A total of 109 lactic acid bacteria isolated from infant faeces were identified by partial 16S rRNA, cpn60 and/or pheS sequencing. Lactobacillus was the most prevalent genus, representing 48% of the isolates followed by Enterococcus (38%). Lactobacillus gasseri (21%) and Enterococcus faecalis (38%) were the main species detected.

Nutritionally enhanced fermented sausages as a vehicle for potential probiotic lactobacilli delivery.

The suitability of three potential probiotic lactobacilli strains (Lactobacillus casei CTC1677, L. casei CTC1678 and Lactobacillus rhamnosus CTC1679), previously isolated from infants' faeces and characterized, and three commercial probiotic strains (Lactobacillus plantarum 299v, L. rhamnosus GG and L.

Assessment of safe enterococci as bioprotective cultures in low-acid fermented sausages combined with high hydrostatic pressure.

Three bacteriocinogenic, non-aminogenic and non-virulent Enterococcus strains (Enterococcus faecium CTC8005, Enterococcus devriesei CTC8006 and Enterococcus casseliflavus CTC8003) were used as starter cultures in low-acid fermented sausages to assess their competitiveness and their bioprotective potential against Listeria monocytogenes and Staphylococcus aureus. The inoculated strains were successfully monitored by RAPD-PCR. All the strains were able to grow, survive and dominate the endogenous enterococci population and avoided the growth of Enterobacteriaceae.

The effect of NaCl-free processing and high pressure on the fate of Listeria monocytogenes and Salmonella on sliced smoked dry-cured ham.

NaCl is an important multifunctional ingredient applied in dry-cured ham elaboration. However, its excessive intake has been linked to serious cardiovascular diseases causing a recent increase in the development of reduced salt products. In the present study Listeria monocytogenes and Salmonella, food-borne pathogens which can cross-contaminate post processed products, were spiked with <100 CFU/g on slices of both standard (S) and NaCl-free processed (F) (elaborated with KCl+potassium lactate instead of NaCl) smoked dry-cured ham.

Prevalence of Salmonella spp. and Listeria monocytogenes at small-scale spanish factories producing traditional fermented sausages.

The manufacturing of fermented sausages is subject to natural contamination processes that can potentially carry foodborne pathogens along the process chain and result in contamination of the final product. The aim of this study was to evaluate the occurrence of Salmonella spp. and Listeria monocytogenes at different sampling points during the manufacturing process of fuet, a type of traditional fermented sausage, at 10 small-scale Spanish factories.

Physical performance of biodegradable films intended for antimicrobial food packaging.

Antimicrobial films were prepared by including enterocins to alginate, polyvinyl alcohol (PVOH), and zein films. The physical performance of the films was assessed by measuring color, microstructure (SEM), water vapor permeability (WVP), and tensile properties. All studied biopolymers showed poor WVP and limited tensile properties.

High hydrostatic pressure and biopreservation of dry-cured ham to meet the Food Safety Objectives for Listeria monocytogenes.

This work aimed to evaluate the effect of nisin application (biopreservation) combined with high hydrostatic pressure processing (HHP) on the behavior of Listeria monocytogenes CTC1034 intentionally inoculated (at ca. 10(7)cells/g) onto the surface of ready-to-eat (RTE) sliced dry-cured ham. Two types of dry-cured ham, which had different water activities and fat contents were studied (a(w) of 0.

Inactivation and recovery of Listeria monocytogenes, Salmonella enterica and Staphylococcus aureus after high hydrostatic pressure treatments up to 900 MPa.

High hydrostatic pressure (HP) processing is used in the food industry to enhance the safety and extend the shelf-life of food. Although a drastic decrease in microbial viability is achieved immediately after the application of HP treatments, under favorable conditions the injured bacteria can recover. The present study evaluated the inactivation and recovery of five strains of Listeria monocytogenes, Salmonella enterica and Staphylococcus aureus subjected to pressures of 400, 600, and 900 MPa under stressing and non-stressing conditions in a complex medium.

Combined effect of enterocin AS-48 and high hydrostatic pressure to control food-borne pathogens inoculated in low acid fermented sausages.

The single and combined effects of enterocin AS-48 and high hydrostatic pressure (HHP) on Listeria monocytogenes, Salmonellaenterica, and Staphylococcus aureus was investigated in fuet (a low acid fermented sausage) during ripening and storage at 7 degrees C or at room temperature. AS-48 (148 AU g(-1)) caused a drastic 5.5 log cfu g(-1) decrease in L.

Modeling the combined effects of enterocins A and B, lactate, and EDTA on the growth of Salmonella at different temperatures.

The effects of enterocins A and B (produced by Enterococcus faecium CTC492), lactate, and ethylenediaminetetraacetic acid (EDTA) on the growth of Salmonella were modeled together with temperature using the response surface methodology. Six serovars of Salmonella enterica were inoculated (ca. 10(3) cells/ml) in brain-heart infusion broth with different levels of the studied factors and then incubated at different temperatures.

Identification of Enterococcus species by melting curve analysis of restriction fragments.

A new method for the identification of Enterococcus species has been developed. It combines PCR amplification of sodA gene and 16S-23S intergenic spacer region with restriction enzyme digestion followed by a melting curve analysis of the restriction fragments (MCARF). All strains analyzed were correctly identified by MCARF.

Inhibition of Salmonella sp. Listeria monocytogenes and Staphylococcus aureus in cooked ham by combining antimicrobials, high hydrostatic pressure and refrigeration.

Recontamination of ready-to-eat products such as cooked ham during post-processing may be the cause of outbreaks of food-borne disease. The effectiveness of the combination of high pressure processing (HPP) at 600MPa with the natural antimicrobials nisin and potassium lactate has been evaluated in sliced cooked ham spiked with 4LogCFU/g of Salmonella sp., Listeria monocytogenes and Staphylococcus aureus after 3-months of storage at 1 and 6°C.

Inhibition of Listeria monocytogenes in cooked ham through active packaging with natural antimicrobials and high-pressure processing.

Enterocins A and B and sakacin K at 200 and 2,000 activity units (AU)/cm2, nisin at 200 AU/cm2, 1.8% potassium lactate, and a combination of 200 AU/cm2 of nisin and 1.8% lactate were incorporated into interleavers, and their effectiveness against Listeria monocytogenes spiked in sliced, cooked ham was evaluated.

High-pressure processing and antimicrobial biodegradable packaging to control Listeria monocytogenes during storage of cooked ham.

The efficiency of combining high-pressure processing (HPP) and active packaging technologies to control Listeria monocytogenes growth during the shelf life of artificially inoculated cooked ham was assessed. Three lots of cooked ham were prepared: control, packaging with alginate films, and packaging with antimicrobial alginate films containing enterocins. After packaging, half of the samples were pressurized.

Protein synthesis in lactic acid and pathogenic bacteria during recovery from a high pressure treatment.

Recovery of injured bacteria after high hydrostatic pressure (HHP) treatment is a key point in food safety. In this study, protein synthesis during the recovery of meat environment bacteria Listeria monocytogenes CTC1011, Lactobacillus sakei 23K, L. sakei CTC494, Enterococcus faecalis CTC6365 and Enterococcus faecium CTC6375 after a 400 MPa HHP treatment was analyzed by two-dimensional gel electrophoresis and peptide mass fingerprinting.