The National Advisory Committee on Microbiological Criteria for Foods developed guidelines for conducting challenge studies on pathogen inhibition and inactivation studies in a variety of foods. The document is intended for use by the food industry, including food processors, food service operators, and food retailers; federal, state, and local food safety regulators; public health officials; food testing laboratories; and process authorities. The document is focused on and limited to bacterial inactivation and growth inhibition and does not make specific recommendations with respect to public health. The Committee concluded that challenge studies should be designed considering the most current advances in methodologies, current thinking on pathogens of concern, and an understanding of the product preparation, variability, and storage conditions. Studies should be completed and evaluated under the guidance of an expert microbiologist in a qualified laboratory and should include appropriate statistical design and data analyses. This document provides guidelines for choice of microorganisms for studies, inoculum preparation, inoculum level, methods of inoculation, incubation temperatures and times, sampling considerations, and interpreting test results. Examples of appropriately designed growth inhibition and inactivation studies are provided.

This content is only available as a PDF.

Author notes

Sponsored by the U.S. Department of Agriculture, Food Safety and Inspection Service; U.S. Department of Health and Human Services, Food and Drug Administration, and Centers for Disease Control and Prevention; U.S. Department of Commerce, National Marine Fisheries Service; and U.S. Department of Defense, Veterinary Service Activity. This article may be reproduced without prior permission.

Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture and other NACMCF sponsoring agencies.