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Related Experiment Video

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Composition and Distribution Analysis of Bioaerosols Under Different Environmental Conditions

Composition and Distribution Analysis of Bioaerosols Under Different Environmental Conditions

Published on: January 7, 2019

On the compositing of samples for qualitative microbiological testing.

¹Ross Biosciences Ltd, Upton Bishop, Ross-on-Wye, UK. basil.jarvis@btconnect.com

Letters in Applied Microbiology

|October 3, 2007

Summary

Compositing food samples for microbiological testing is permissible if the testing method is sufficiently sensitive. This approach allows for testing larger combined samples, such as 3 x 250g, instead of multiple smaller ones (e.g., 30 x 25g), without statistical difference.

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Area of Science:

Food Microbiology
Analytical Chemistry
Regulatory Science

Background:

Legislative microbiological criteria for foods necessitate increased testing by laboratories.
Increased testing leads to consideration of sample compositing for efficiency.

Purpose of the Study:

To summarize statistical and practical aspects of compositing sample units for food compliance testing.
To evaluate the permissibility of compositing replicate sample units for microbiological criteria assessment.

Main Methods:

Statistical analysis of compositing versus individual sample testing.
Consideration of 'fit for purpose' methodology for sensitivity in composite samples.

Main Results:

No statistical difference exists between testing multiple small units or fewer larger composite units if the method is appropriate.
Compositing is valid only if the method can detect target organisms in the larger quantity.

Conclusions:

Sample compositing is a statistically valid approach for food microbiological compliance testing.
Method validation for sensitivity with composite samples is crucial for accurate results.