EU Interlaboratory comparison study food VII (2015) : Detection of Salmonella in whole liquid chicken egg
Series/Report no.
RIVM rapport 2016-0042Type
OnderzoeksrapportLanguage
enMetadata
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EU Interlaboratory comparison study food VII (2015) : Detection of Salmonella in whole liquid chicken eggTranslated Title
EU Ringonderzoek voedsel VII (2015) : Detectie van Salmonella in vloeibaar heel kippeneiPubliekssamenvatting
In 2015, it was shown that all 36 National Reference Laboratories (NRLs) in the European Union were able to detect high and low levels of Salmonella in whole liquid chicken egg. One NRL reported positive results for two blank whole liquid egg samples, a possible explanation may be cross-contamination. In a follow-up study this laboratory scored all samples correctly and achieved the level of good performance. The laboratories detected Salmonella in all contaminated samples. In this report we present some of the conclusions of the 7th EU Interlaboratory Comparison Study of Food Samples, which was organised by the European Union Reference Laboratory for Salmonella (EURL-Salmonella).Interlaboratory comparison study obligatory for EU Member States
The study was conducted in September 2015, with a follow-up study in January 2016. Participation was obligatory for all EU Member State NRLs that are responsible for the detection of Salmonella in food samples. EURL-Salmonella is part of the Dutch National Institute for Public Health and the Environment (RIVM).
The laboratories used internationally accepted analysis methods to detect the presence of Salmonella in whole liquid chicken egg samples. Each laboratory received a package with whole liquid egg samples contaminated with two different concentrations of Salmonella Enteritidis or containing no Salmonella at all. The laboratories were required to analyse the samples for the presence of Salmonella in accordance with the study protocol.
Preparation of samples
In this study, for the first time, liquid egg samples were used that had been artificially contaminated with a diluted culture of Salmonella at the laboratory of EURL-Salmonella. The results showed that this method of contamination, which had been used and tested in earlier studies involving food matrices (meat), animal feed and products of the primary production stage, could also be used for whole liquid egg
In 2015 waren alle 36 Nationale Referentie Laboratoria (NRL's) in de Europese Unie in staat om concentraties Salmonella in vloeibaar kippenei aan te tonen, zowel bij hoge als lage concentraties. Eén NRL slaagde er niet in om alles de eerste keer goed uit te voeren, maar wel tijdens de herkansing. Dit blijkt uit het zevende voedselringonderzoek dat is georganiseerd door het referentielaboratorium van de Europese Unie voor Salmonella (EURL-Salmonella).
Ringonderzoek verplicht voor Europese lidstaten
Het onderzoek is in september 2015 gehouden, de herkansing was in januari 2016. Alle NRL's van de Europese lidstaten die verantwoordelijk zijn voor de opsporing van Salmonella in voedsel, zijn verplicht om aan het onderzoek deel te nemen. Het EURL-Salmonella is gevestigd bij het Nederlandse Rijksinstituut voor Volksgezondheid en Milieu (RIVM).
De laboratoria toonden de Salmonella-bacterie in kippenei aan met behulp van de internationaal erkende analysemethoden. Elk laboratorium kreeg een pakket toegestuurd met vloeibaar kippenei dat ofwel besmet was met Salmonella Enteritidis in twee verschillende concentraties, of geen Salmonella bevatte. De laboratoria dienden volgens een protocol te onderzoeken of de monsters Salmonella bevatten.
Monsterbereiding
In eerdere studies zijn voedsel (gehakt), dierlijke mest en dierenvoer op het laboratorium van het EURL-Salmonella kunstmatig besmet met een verdunde cultuur van Salmonella. In deze studie is voor het eerst vloeibaar kippenei kunstmatig besmet en is bewezen dat ook deze werkwijze geschikt is
Sponsors
European Commission, Directorate-General for Health and Food Safety (DG-Sante)Collections
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