Sampling Techniques

  • Thomas B. Whitaker
Part of the Methods in Molecular Biology™ book series (MIMB, volume 157)


It is important to be able to detect and quantify the mycotoxin concentration in food and feedstuffs destined for human and animal consumption. In research, regulatory, and quality assurance activities, correct decisions concerning the fate of commercial lots can only be made if mycotoxin test procedures are accurate and precise. However, it is difficult to estimate accurately and precisely the mycotoxin concentration in a large bulk lot because of the large variability associated with the mycotoxin test procedure (1, 2, 3, 4, 5, 6, 7, 8). A mycotoxin test procedure is a complicated process and generally consists of 3 steps: (a) a sample is taken from the lot, (b) the sample is ground in a mill to reduce particle size, and a subsample is removed from the comminuted sample for extraction, and (c) the mycotoxin is extracted from the comminuted subsample and quantified. There have been several reviews published describing accepted procedures for sampling, sample preparation, and analysis for agricultural commodities (8, 9, 10, 11, 12, 13, 14, 15). Even when using accepted procedures, there are errors (the term error will be used to denote variability) associated with each of the above steps of the mycotoxin test procedure. Because of these errors, the true mycotoxin concentration in the lot cannot be determined with 100 percent certainty by measuring the mycotoxin concentration in the sample taken from the lot.


High Performance Liquid Chromatography High Performance Liquid Chromatography Method Subsample Size Thin Layer Chromatography Method Peanut Kernel 
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Copyright information

© Humana Press Inc. 2001

Authors and Affiliations

  • Thomas B. Whitaker
    • 1
  1. 1.North Carolina State University, USDA/ARSRaleigh

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