117 research outputs found
The STARTEC decision support tool for better tradeoffs between food safety, quality, nutrition, and costs in production of advanced ready‐to‐eat foods
No full textTaran Skjerdal et al.This article has been corrected: September 26, 2018. Article: Corrigendum to “The STARTEC Decision Support Tool for Better Tradeoffs between Food Safety, Quality, Nutrition, and Costs in Production of Advanced Ready‐to‐Eat Foods”A prototype decision support IT-tool for the food industry was developed in the STARTEC project. Typical processes and decision steps were mapped using real life production scenarios of participating food companies manufacturing complex ready-to-eat foods. Companies looked for a more integrated approach when making food safety decisions that would align with existing HACCP systems. The tool was designed with shelf life assessments and data on safety, quality, and costs, using a pasta salad meal as a case product. The process flow chart was used as starting point, with simulation options at each process step. Key parameters like pH, water activity, costs of ingredients and salaries, and default models for calculations of Listeria monocytogenes, quality scores, and vitamin C, were placed in an interactive database. Customization of the models and settings was possible on the user-interface. The simulation module outputs were provided as detailed curves or categorized as “good”; “sufficient”; or “corrective action needed” based on threshold limit values set by the user. Possible corrective actions were suggested by the system. The tool was tested and approved by end-users based on selected ready-to-eat food products. Compared to other decision support tools, the STARTEC-tool is product-specific and multidisciplinary and includes interpretation and targeted recommendations for end-users.The work was carried out in the EU funded project STARTEC—Decision support tools to ensure safe, tasty and nutritious advanced ready-to-eat foods for healthy and vulnerable consumers (Project no. 289262).Peer reviewe
Modelling the growth kinetics of Listeria monocytogenes in pasta salads at different storage temperatures and packaging conditions
No full textThe aim of this study was to model Listeria monocytogenes growth kinetics in ready to eat full meal pasta salads, containing fresh and cooked ingredients. With this aim, laboratory prepared salads, representing two formulations of commercial pasta salads, were spiked with L. monocytogenes and tested under categorised packaging and storage temperature conditions. L. monocytogenes enumeration results collected in 15 different laboratory prepared salad datasets were analysed with primary and secondary models. The models showing the best fit to describe L. monocytogenes growth kinetics in the laboratory prepared salads were then validated within commercial pasta salads. Baranyi no-lag was the best primary model fitting datasets collected at 12 °C, whereas the exponential model gave the best results for datasets collected at 4 °C. The maximum microbial specific growth rate (μmax) mean values obtained at 4 and 12 °C for salads packaged under air packaging conditions were 0.008 ± 0.003 and 0.036 ± 0.006 log10(cfu/g) h−1, respectively. At the same temperatures, the μmaxmean values obtained under modified atmosphere were 0.005 ± 0.005 and 0.026 ± 0.005 log10(cfu/g) h−1, respectively. The Gamma secondary model predicted the growth kinetics of L. monocytogenes at both temperatures and packaging conditions and the μmaxat the optimum temperature and the optimum pH for Listeria growth (μopt) estimated by the model corresponded to 0.247 ± 0.009 log10(cfu/g) h−1. Baranyi model without lag phase was used to generate growth kinetics under different scenarios. In the comparison of the predicted log10concentrations respect to the observed ones the residues rarely exceeded 1 Log10cfu/g. The selected models can be applied to describe the growth kinetics of L. monocytogenes in similar types of pasta salads with comparable pH, shelf life and storage conditions
Mapping the surveillance activities for food-hazards across Europe
No full textAim: MATRIX is part of the One Health European Joint Programme aiming at the implementation of One Health Surveillance
(OHS), through the strengthening of the whole process of surveillance, and the implementation of guidelines for OHS
improvement. The Project relies on a problem-based approach and focuses on four hazard-tracks: Salmonella, Listeria,
Campylobacter and an emerging threat. As Work Package 2, a mapping of the surveillance chain across all sectors for each
hazard-track has been performed from late 2020 to early 2021.
Methods: Per each hazard-track, including Hepatitis E selected as the emerging pathogen of interest, a specific food chain
was selected to explore in detail the different realities. Twelve online questionnaires were implemented based on the ”farm to
fork” approach for the three sectors (animal health, food safety and public health) and each hazard-food chain combination.
Surveillance activities in place were investigated in at least two countries for each combination.
Results: Salmonella was investigated in humans and pork meat food chain; Listeria in humans and dairy products;
Campylobacter in humans and poultry meat; Hepatitis E, in humans and wild boar meat. Answers were categorized in order to be graphically displayed, in: events, actors, data, metadata, event producing data, identified data sources, and sharing potential. Answers of these categories represent the start to identificate cross-sectorial linkages across surveillance chains.
Conclusions: The mapping of surveillance activities in place was the first step in the identification of best-practices for multisectorial collaboration. The following phase is the identification of outputs that could be shared for One Health oriented
decision-making
Food safety of salt-cured cod products : effects of salt-curing, rehydration and thermal treatmenton survival, growth and invasiveness of Listeria spp.
No full textSalt-cured and dried salt-cured (klipfish) cod (Gadus morhua L.) are highly appreciated. Salt fish and klipfish are mainly prepared by rehydration to lower the level of salt. The rehydrated cod can be used in several dishes and consumption of these products has been considered safe due to the high level of salt. The overall aim of the thesis was to study the food safety of salt-cured fish products using Listeria spp. as an indicator.
Initially, we studied the survival of Listeria spp. in muscle of cod during salt-curing and growth during chilled storage of the rehydrated product. These experiments demonstrated that long term exposure to high salt concentrations did not eliminate Listeria spp., and that Listeria spp. being present in the fish prior to salt-curing could recover and grow in rehydrated salt-cured cod during chilled storage.
Afterwards, the thermal inactivation at 55 and 60 ºC and growth potential at 4 and 8 ºC of L. innocua in rehydrated salt-cured cod was studied. The results demonstrated that both level of salt stress and matrix i.e. rehydrated or fresh cod muscle, did affect the thermal inactivation of L. innocua towards non-linearity with an upward concavity. During subsequent storage of the thermally treated samples, the lag time of the strain was 9-10 days regardless of salt stress level or matrix. In the raw products (controls), however, the lag time varied with salt stress level and matrix.
Finally, the ability of L. monocytogenes to cause listeriosis after salt stress, i.e. invasiveness, was studied. L. monocytogenes was exposed to either no salt or a salt stress period comparable to that applied in the production of salt-cured cod. The results show that extreme salt-stress exposure attenuated the invasiveness of
L. monocytogenes whereas the invasiveness was significantly higher for the non salt stressed strains. As the invasiveness correlates with bacterial virulence, the results suggests that L. monocytogenes represent a lower food safety risk when exposed to salt-curing with extreme NaCl concentrations than when exposed to a constant and low level of salt
Produksjon av fermentert fiskesaus fra nedklasset saltfisk, sild,pyllorus og startkultur
No full textDet nedklasses og kasseres årlig flere titalls tonn saltfisk og klippfisk. I dette prosjektet er det undersøkt om denne ressursen kan nyttegjøres i produksjon av fermentert fiskesaus. Fiskesaus er et utbredt produkt i Sør-Øst Asia. Den framstilles ved å la to deler fisk og en del salt stå til det har blitt en gylden saus med fyldig aroma. Dette tar fra 6 måneder til 2 år. Målet med prosjektet er å identifisere og karakterisere halofile bakterier som gir gunstig og rask smaksutvikling i fermentert fiskesaus, og anvende disse til produksjon av startkulturer og fiskesaus fra nedklasset saltfisk. Forsøkene har vist at de kan produseres fiskesaus fra saltfisk uten andre tilsetninger enn vann og salt, men modningsprosessen tar mer enn 2 år. Tilsetning av smaksutviklende bakterier, torskeslo og sild gir imidlertid moden saus av god kvalitet i løpet av 6-8 måneder. De smaksutviklende isolatene er funnet etter analyser av ca 220 bakterieisolater fra saltfisk og fiskesaus. Den mest effektive bakterien for produksjon av fiskesaus er en rødmiddbakterie. Arbeidet med kultursamlingen har gitt mange nye ideer til anvendelse av nedklasset saltfisk. Samlingen er et godt utgangspunkt for bioprospektering av biokjemikalier som er tilpasset høye eller vekslende saltkonsentrasjoner. Prosjektet har også gitt verdifulle kunnskap for produktutvikling i saltfiskindustrien. Denne rapporten er, med unntak av kapittel 6, identisk med sluttrapporten til Norges Forskningsråd for prosjektet “Identifisering av halofile bakterier for rask produksjon av fiskesaus fra nedklasset saltfisk”.Rapport/Report 13/2001 English summaryProduksjon av fermentert fiskesaus fra nedklasset saltfisk, sild,pyllorus og startkulturpublishedVersio
Effekten av stressfaktorer i matkjeden på Listeria monocytogenes
No full textThe work presented in this thesis was carried out at Section for Food Bacteriology, Unit Food Safety, Antimicrobial Resistance and Zoonoses, Research section for Food Safety and Animal Health at the Veterinary Institute and Department of Paraclinical Sciences at the Faculty of Veterinary Medicine NMBU in Oslo. The work was carried out between 2014 and 2019.Listeria monocytogenes is the causative agent of food-borne listeriosis, a disease often transmitted by contaminated Ready-To-Eat (RTE) food. Immunosuppressed individuals, fetuses, and the elderly are at higher risk of developing a lethal form of listeriosis. Despite preventive actions taken against L. monocytogenes contamination of food, human listeriosis is still a food safety challenge. L. monocytogenes is a robust ubiquitous soil bacterium that is highly resistant to several stressors in the food chain, from farm to the human host. It is therefore difficult to eradicate it from raw food material and food processing environments. However, avoiding contamination and subsequent inhibiting growth of the bacterium in the food are important and highly prioritized preventive measures taken by the food industry. L. monocytogenes’ ability to persist in the food environment and to cause severe disease makes it a costly foodborne pathogen to control both in the food industry and in the society. This PhD project has explored how L. monocytogenes copes with a selected set of stressors present in the food, in the environment and in the human host, focusing on the aim of increasing food safety.L. monocytogenes er årsaken til matbåren listeriose, en sykdom som ofte er forårsaket av spiseklar mat (Ready-To-Eat, RTE) som er forurenset med L. monocytogenes. Individer med nedsatt immunforsvar, fostre og eldre har høyere risiko for å få listeriose med dødelig utfall. Til tross for forebyggende tiltak mot L. monocytogenes i mat, er listeriose hos mennesker fortsatt en utfordring for mattryggheten. L. monocytogenes er en robust bakterie som finnes nesten overalt og som er svært resistent mot mange stressfaktorer i matkjeden. Den er derfor vanskelig å eliminere fra råvarer og fra matproduskjonsmiljøer. Til tross for dette er det høyt prioritert av matindustrien å iverksette forebyggende tiltak for å redusere forurensning med L. monocytogenes og påfølgende vekst av denne bakterien i matproduktene. L. monocytogenes evne til å persistere i miljøet og dens evne til å forårsake alvorlig sykdom gjør at den er en kostbar matbåren bakterie for både matindustrien og for samfunnet. Med mål om å styrke mattryggheten har dette PhD prosjektet undersøkt hvordan L. monocytogenes håndterer ulike stressfaktorer som finnes i mat, i miljøet og i mennesket som vertsorganisme.Veterinærinstitutte
The effect of food chain stressors on Listeria monocytogenes
No full textListeria monocytogenes is the causative agent of food-borne listeriosis, a disease often transmitted by contaminated Ready-To-Eat (RTE) food. Immunosuppressed individuals, fetuses, and the elderly are at higher risk of developing a lethal form of listeriosis. Despite preventive actions taken against L. monocytogenes contamination of food, human listeriosis is still a food safety challenge. L. monocytogenes is a robust ubiquitous soil bacterium that is highly resistant to several stressors in the food chain, from farm to the human host. It is therefore difficult to eradicate it from raw food material and food processing environments. However, avoiding contamination and subsequent inhibiting growth of the bacterium in the food are important and highly prioritized preventive measures taken by the food industry. L. monocytogenes’ ability to persist in the food environment and to cause severe disease makes it a costly foodborne pathogen to control both in the food industry and in the society. This PhD project has explored how L. monocytogenes copes with a selected set of stressors present in the food, in the environment and in the human host, focusing on the aim of increasing food safety
Staphylococcus aureus fra melk og melkeprodukter i Etiopia : forekomst, enterotoksigenisk potensiale, antibiotikaresistens og spa typer
No full textMilk production in Ethiopia is increasing. However, due to unhygienic and traditional milk production and processing practices the issue of milk safety remains a challenge. If these safety issues are not properly addressed, the high nutritional composition and neutral pH of milk may convey many milk-borne pathogens, including Staphylococcus aureus, which imposes health risks to the consumer. S. aureus is an important food-borne pathogen globally as it can cause staphylococcal food poisoning (SFP) and also readily develops antibiotic resistance.
The objectives of this study were: i) to study the distribution of S. aureus and other Staphylococcus species in milk and milk products along the milk value chain of the studied area; ii) to assess the enterotoxigenic potential of the S. aureus isolates; iii) to evaluate the antimicrobial resistance profiles of the S. aureus isolates to 12 antibiotics commonly used in the studied area and verify the presence or absence of methicillin-resistant S. aureus (MRSA) iv) to assess the genetic relatedness of the enterotoxigenic and multidrug resistance (MDR) S. aureus strains using spa tying method; v) evaluate the performance of real time PCR (qPCR) targeting the nuc gene for quantification of S. aureus in bulk milk, in comparison with the plate count method.Melkeproduksjon øker i Etiopia. Imidlertid er mikrobiologisk trygghet av melk en utfordring på grunn av uhygienisk og tradisjonell melkeproduksjon og prosessering. Om disse sikkerhetsaspektene ikke blir tilstrekkelig adresserte, kan melkens høye næringsinnhold og nøytrale pH føre til at melk blir bærer av mange matbårne patogener, inkludert Staphylococcus aureus. Dette representerer en helserisiko for konsumenten. S. aureus er en viktig matbåren patogen fordi den kan forårsake stafylokokkintoksikasjon, og lett kan utvikle antibiotikaresistens.
Målene for dette studiet var: i) å studere distribusjon av S. aureus og andre Staphylococcus arter i melk og melkeprodukter langs verdikjeden i Tigray regionen; ii) å vurdere potensialet for enterotoksinproduksjon hos S. aureus isolatene; iii) å evaluere resistens hos S. aureus isolatene mot 12 ulike antibiotika som brukes ofte i Tigray regionen, samt verifisere tilstedeværelse av meticillin-resistente (MRSA); iv) å vurdere genetisk slektskap, ved hjelp av spa-typing, hos de enterotoksigene og antibiotikaresistente (MDR) isolatene; v) evaluere kvantifisering av S. aureus i melk ved hjelp av real time PCR (qPCR ) basert på nuc genet, sammenlignet med platetelling
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