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Stuttgart Mühlhausen, Germany

Crews C.,UK Environment Agency | Chiodini A.,L.E.S.S. | Granvogl M.,German Research Institute for Food Chemistry DFA | Hamlet C.,Lord Rank Center | And 8 more authors.
Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment | Year: 2013

Esters of 2 - and 3-monochloropropane-1,2-diol (MCPD) and glycidol esters are important contaminants of processed edible oils used as foods or food ingredients. This review describes the occurrence and analysis of MCPD esters and glycidol esters in vegetable oils and some other foods. The focus is on the analytical methods based on both direct and indirect methods. Methods of analysis applied to oils and lipid extracts of foods have been based on transesterification to free MCPD and determination by gas chromatography-mass spectrometry (indirect methods) and by high-performance liquid chromatography-mass spectrometry (direct methods). The evolution and performance of the different methods is described and their advantages and disadvantages are discussed. The application of direct and indirect methods to the analysis of foods and to research studies is described. The metabolism and fate of MCPD esters and glycidol esters in biological systems and the methods used to study these in body tissues studies are described. A clear understanding of the chemistry of the methods is important when choosing those suitable for the desired application, and will contribute to the mitigation of these contaminants. © 2013 Copyright Taylor and Francis Group, LLC. Source

Ball I.,University of Hohenheim | Hoferer M.,Chemisches und Veterinaruntersuchungsamt | Marschang R.E.,University of Hohenheim | Marschang R.E.,Laboklin GmbH and Co. KG
Journal of Veterinary Diagnostic Investigation | Year: 2014

A cell line was established from whole 6-8-week-old central bearded dragon (Pogona vitticeps) embryos. Cells were mid-sized and showed an elongated and polymorphic form. The cell line grew in a monolayer and has been serially passaged for 17 passages at time of publication. This cell line has been used with samples from adenovirus polymerase chain reaction (PCR)-positive bearded dragons, and 2 virus isolates have been obtained so far. The isolates show a clear cytopathic effect in inoculated cells. Both virus isolates have been serially passaged on this cell line, and have been identified by PCR amplification and sequencing of a portion of the DNA-dependent DNA polymerase gene and show 100% nucleotide identity to the corresponding region of an agamid adenovirus. Electron microscopic examination of supernatant from infected cells demonstrated the presence of nonenveloped particles, with a diameter of approximately 80 nm in both virus isolates. © 2014 The Author(s). Source

Mol H.G.J.,RIKILT Wageningen UR | Zomer P.,RIKILT Wageningen UR | Garcia Lopez M.,UK Environment Agency | Fussell R.J.,UK Environment Agency | And 7 more authors.
Analytica Chimica Acta | Year: 2015

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is one of the most widely used techniques for identification (and quantification) of residues and contaminants across a number of different chemical domains. Although the same analytical technique is used, the parameters and criteria for identification vary depending on where in the world the analysis is performed and for what purpose (e.g. determination of pesticides, veterinary drugs, forensic toxicology, sports doping). The rationale for these differences is not clear and in most cases the criteria are essentially based on expert opinions rather than underpinned by experimental data. In the current study, the variability of the two key identification parameters, retention time and ion ratio, was assessed and compared against requirements set out in different legal and guidance documents. The study involved the analysis of 120 pesticides, representing various chemical classes, polarities, molecular weights, and detector response factors, in 21 different fruit and vegetable matrices of varying degrees of complexity. The samples were analysed non-fortified, and fortified at 10, 50 and 200μgkg-1, in five laboratories using different LC-MS/MS instruments and conditions. In total, over 135,000 extracted-ion chromatograms were manually verified to provide an extensive data set for the assessment. The experimental data do not support relative tolerances for retention time, or different tolerances for ion ratios depending on relative abundance of the two product ions measured. Retention times in today's chromatographic systems are sufficiently stable to justify an absolute tolerance of ±0.1min. Ion ratios are stable as long as sufficient response is obtained for both product ions. Ion ratio deviations are typically within ±20% (relative), and within ±45% (relative) in case the response of product ions are close to the limit of detection. Ion ratio tolerances up to 50% did not result in false positives and reduced the false negative rate for pesticides with product ions in the low S/N range to <5%. Without ion ratio criterion, two false positives were obtained in 105 non-fortified samples. Although the study has been conducted for pesticides residues in fruits and vegetables, the impact of these findings is believed to extend towards other application areas and possibly support adjustment or consolidation of criteria across other analytical domains. © 2015 Elsevier B.V. Source

Bartholoma A.,Chemisches und Veterinaruntersuchungsamt | Schering B.,Chemisches und Veterinaruntersuchungsamt | Horn D.,Chemisches und Veterinaruntersuchungsamt
Fleischwirtschaft | Year: 2013

The term "dry aged beef" summarises a heterogeneous product group of dry maturated beef with considerable differences concerning conditions of maturation and marketing. With regard to hygienic standards and duration of maturation, dry aged beef can turn out to be risk food contaminated with pathogenic microorganisms, (myco-) toxins, and biogenic amines. In a market survey the sensory, microbiological and histological properties and the amount of biogenic amines and mycotoxins in samples of dry aged beef from 5 producers were determined. Pathogenic microorganisms were not detected in the analysed samples, nevertheless, some samples displayed high bacterial counts of proteolytes as well as diverse biogenic amines. Under the current legislation, the classification of the products as "fresh meat" or "treated raw meat" with interconnected demands toward the producer have to be taken into consideration. Selling short time aged beef or wet aged beef as dry aged beef can be judged as deception. Source

Sting R.,Chemisches und Veterinaruntersuchungsamt | Molz K.,Chemisches und Veterinaruntersuchungsamt | Benesch C.,Chemisches und Veterinaruntersuchungsamt
Berliner und Münchener tierärztliche Wochenschrift | Year: 2013

This is a case report about a Q fever infection of a goat herd with abortions and excretions of pathogens accompanied by human infection and disease. Following a diagnosis of Q fever in a goat herd, all animals were vaccinated with an inactivated phase 1 vaccine. The herd was kept isolated and animals were neither removed nor introduced so that monitoring of the course of the Q fever infection of the individual dam was possible. Over a period of two years following the diagnosis of a Q fever infection (abortion), diagnostic investigations on detection of Coxiella (C.) burnetii were performed using quantitative Real-Time PCR (qPCR) and for serological studies complement fixation test (CFT) and ELISA. Excretion of pathogens decreased from > 500 000 units per genital swab in the first year to < 50 units in the second year after the initial diagnosis. Serological studies of the dams using CFT revealed a dominance of phase 2 antibodies with a proportion of 35.4% (17/48) positive animals in 2006. This level decreased to a value of 2.3% (2/87) two years later. The mixed phase 1 and 2 ELISA initially yielded 20.8% (10/48) positive dams with an increase to 98.9% (86/87) two years later. The control measures which were implemented after a round table meeting are illustrated and discussed. Source

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