Sampling hazelnuts for aflatoxin: uncertainty associated with sampling, sample preparation, and analysis.

Guner Ozay; Ferda Seyhan; Aysun Yilmaz; Thomas B Whitaker; Andrew B Slate; Francis Giesbrecht

PubMed · 16915837

Sampling hazelnuts for aflatoxin: uncertainty associated with sampling, sample preparation, and analysis.

Guner Ozay·Ferda Seyhan·Aysun Yilmaz·Thomas B Whitaker·Andrew B Slate·Francis Giesbrecht

Abstract

The variability associated with the aflatoxin test procedure used to estimate aflatoxin levels in bulk shipments of hazelnuts was investigated. Sixteen 10 kg samples of shelled hazelnuts were taken from each of 20 lots that were suspected of aflatoxin contamination. The total variance associated with testing shelled hazelnuts was estimated and partitioned into sampling, sample preparation, and analytical variance components. Each variance component increased as aflatoxin concentration (either B1 or total) increased. With the use of regression analysis, mathematical expressions were developed to model the relationship between aflatoxin concentration and the total, sampling, sample preparation, and analytical variances. The expressions for these relationships were used to estimate the variance for any sample size, subsample size, and number of analyses for a specific aflatoxin concentration. The sampling, sample preparation, and analytical variances associated with estimating aflatoxin in a hazelnut lot at a total aflatoxin level of 10 ng/g and using a 10 kg sample, a 50 g subsample, dry comminution with a Robot Coupe mill, and a high-performance liquid chromatographic analytical method are 174.40, 0.74, and 0.27, respectively. The sampling, sample preparation, and analytical steps of the aflatoxin test procedure accounted for 99.4, 0.4, and 0.2% of the total variability, respectively.

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Aflatoxins Chemistry Techniques, Analytical Chromatography, High Pressure Liquid Corylus Food Analysis Food Contamination Models, Theoretical Quality Control Regression Analysis Reproducibility of Results Water Journal Article Research Support, Non-U.S. Gov't

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Guner Ozay, Ferda Seyhan, Aysun Yilmaz, Thomas B Whitaker, Andrew B Slate, Francis Giesbrecht. Sampling hazelnuts for aflatoxin: uncertainty associated with sampling, sample preparation, and analysis.. https://pubmed.ncbi.nlm.nih.gov/16915837/

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