The Use of Indicators and Surrogate Microorganisms for the Evaluation of Pathogens in Fresh and Fresh-Cut Produce
Indicators and surrogate microorganisms are used for a variety of purposes in food systems including evaluating quality or safety of raw or processed food products and validating effectiveness of microbial control measures. Although frequently used on an informal basis within a specific company, the use of indicators is highly dependent upon the microbiological criteria that are in place for the food product. All the considerations that must be addressed in establishing microbiological criteria must also be in place if indicators or surrogates are to be utilized in process verification. This chapter is limited to a discussion of the challenges of selecting an indicator or surrogate to assure safety for specific individual produce items and associated conditions (that is, growing, harvesting, processing, handling, storage and packaging) or for determining microbial reduction treatment effectiveness (for example, water treatment or manure composting effectiveness or decontamination procedures).