LABORATORY MANUAL OF FOOD MICROBIOLOGY FOR ETHIOPIAN HEALTH AND NUTRITION RESEARCH INSTITUTE (FOOD MICROBIOLOGY LABORATORY)

LABORATORY MANUAL OF  FOOD MICROBIOLOGY FOR ETHIOPIAN HEALTH AND NUTRITION RESEARCH INSTITUTE (FOOD MICROBIOLOGY LABORATORY)
Introduction
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.
The application of these standards, guidelines and recommendations is intended to prevent or
eliminate hazards in foods or reduce them to acceptable levels. This requires an elaborate
laboratory with equipment and personnel well trained to carry out the analysis. Most developing
countries lack the resources to put up food microbiology laboratories and to man them
adequately to international standards. The globalization of food trade and increasing problems
worldwide with emerging and re-emerging foodborne diseases have increased the risk of crossborder transmission of infectious agents. Because of the global nature of food production,
manufacturing, and marketing, infectious agents can be disseminated from the original point of
processing and packaging to locations thousands of miles away. In this regard, developing
countries are required to ensure that their sanitary and phytosanitary measures are based on an
assessment, as appropriate to the circumstances, of the risks to human, animal or plant life or
health, taking into account the risk assessment techniques developed by the relevant international
organizations. The manual details microbiological risk assessment of various food categories,
guidelines and recommendations related to food safety. There is a critical need for technical
advice on risk assessment of microbiological hazards in foods to meet the needs of national
governments, the food industry, the scientific community, trade organizations and international
consumer groups. UNIDO, FAO and WHO have a direct role to play in assisting developing
countries in matters related to food safety and should strengthen efforts to facilitate access to
specific advice on microbiological risk assessment. This manual has been developed with the help
of UNIDO inline with the above stated spirit.