The purpose of this manual is to provide the new food microbiology laboratory at the Ethiopian
Health and Nutrition Research Institute with the standard methods for qualitative and quantitative
detection of microorganisms in food and water. The manual contains detailed description of
microbial enumeration, isolation and identification of pathogenic food-borne bacteria. Methods of
estimating sanitary indicator microorganisms as well as enumeration of moulds and yeasts are
documented. These methods have been adapted from methods recommended by the ICMSF,
AOAC, FDA, APHA and Health Canada. The standard operating procedures and quality
control guidelines relating to food sampling and methods of analysis are included. The manual is
written in such a manner that it can be used for in-house training of new technicians. Description
of equipment maintenance and calibration is detailed including quality control of media and
internal laboratory audit. Isolation and identification of microbial food contaminants help to
understand how infectious agents enter and spread through the food chain and therefore come up
with procedures to prevent or minimize exposure of the consumer to such agents. There is the
need to estimate the risk that foodborne pathogens pose to human health in a national and
international context and to identify possible interventions to reduce or eliminate these risks. The
standards, guidelines and recommendations adopted by international trade agreements, such as
those administered by the WTO, are playing an increasingly important role in protecting the health
of consumers. In the case of microbiological hazards, Codex has elaborated standards, guidelines
and recommendations that describe processes and procedures for the safe preparation of food.