Fachbereich Veterinärmedizin


Service-Navigation

    Publikationsdatenbank

    Comparison of manual and automatic sampling for monitoring ochratoxin A in barley grain (2011)

    Art
    Zeitschriftenartikel / wissenschaftlicher Beitrag
    Autoren
    Andersson, M G
    Reiter, E V
    Lindqvist, P-A
    Razzazi-Fazeli, E
    Häggblom, P
    Quelle
    Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment; 28(8) — S. 1066–1075
    ISSN: 1944-0049
    Sprache
    Englisch
    Verweise
    DOI: 10.1080/19440049.2011.576438
    Pubmed: 21598140
    Kontakt
    Institut für Tierernährung

    Königin-Luise-Str. 49
    Gebäude 8
    14195 Berlin
    Tel.+49 30 838 52256 Fax.+49 30 838-55938
    email:tierernaehrung@vetmed.fu-berlin.de

    Abstract / Zusammenfassung

    Automatic and manual sampling for ochratoxin A (OTA) in barley grain was compared under industrial conditions considering sampling uncertainty as well as practical and technical aspects. Ten tonnes of barley inoculated with Penicillium verrucosum were incubated until the OTA concentration reached approximately 15 µg kg(-1) and sampled with manual and automatic sampling. A nested experimental design and ANOVA was used to estimate variance components from sampling, sample reduction, sample preparation and analysis. Manual sampling resulted in a high sampling uncertainty and OTA concentrations in aggregate samples ranged from 2 to 80 µg kg(-1). When aggregate samples were formed by automatic sampling the uncertainty arising from nugget effects and spatial distribution was practically eliminated. Results from this study show that an automatic sampler mounted after a mixer or conveyer can provide representative samples of OTA from a moving stream of barley. Automatic sampling might present a practical and economical alternative to manual sampling for feed mill operators when monitoring low levels of mycotoxins in grain or other commodities. Despite careful precautions, sample preparation and analysis resulted in a relative uncertainty of ±40% (p = 0.95), which was attributed to the sub-sampling following the two grinding steps. Size fractionation of the coarsely ground barley showed that 40% of the total amount of OTA was present in a small fraction of fine particles with a strong tendency to aggregate or stick to equipment and containers. Thus, in order to take advantage of the automatic sampling, it is crucial to apply an appropriate sub-sampling to prevent segregation of particles which may affect the OTA measurements.