Low-moisture foods (LMF) are foods that are naturally low in moisture or are produced from higher moisture foods through drying or dehydration processes. These foods typically have a long shelf life and have been perceived for many years to not represent microbiological food safety risk hazards. However, in recent years, a number of outbreaks of foodborne illnesses linked to LMF has illustrated that despite the fact that microorganisms cannot grow in these products, bacteria do have the possibility to persist for long periods of time in these matrices. Responding to a request from the Codex Committee on Food Hygiene (CCFH), the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) implemented a series of activities aimed at collating and analysing the available information on microbiological hazards related to LMF and ranking the foods of greatest concern from a microbiological food safety perspective. Seven categories of LMF which were ultimately included in the ranking process, and the output of the risk ranking, in descending order was as follows: cereals and grains; dried protein products; spices and dried herbs; nuts and nut products; confections and snacks; dried fruits and vegetables; and seeds for consumption.

This document provides guidance on undertaking risk assessment of all microbial hazards which may adversely affect human health in foods along a food chain. This document is also intended to provide practical guidance on a structured framework for carrying out risk assessment of microbiological hazards in foods, focussing on the four components including hazard identification, hazard characterization, exposure assessment and risk characterization. These guidelines therefore represent the best practice at the time of their preparation, and it is hoped that they will help stimulate further developments and disseminate the current knowledge.

Lipid-based ready-to-use foods (RUFs) for the nutritional management of moderate acute malnutrition (MAM) and severe acute malnutrition (SAM) are provided to children from 6 months to 59 months of age within the context of emergency feeding programmes supervised by governments. Based on the review, the expert committee considered that children with SAM have an increase in susceptibility to bacteraemia and sepsis that is probably between twofold and fivefold compared with children who are not malnourished and are of the same age and live in the same communities. On the basis of its common occurrence as a cause of infections and serious illnesses in children with SAM, and its documented ability to contaminate, survive in, and cause outbreaks of illness associated with low-moisture foods similar to RUFs, the expert committee concluded that Salmonella is the pathogen of most concern in lipid-based RUFs.Many outbreaks of foodborne salmonellosis have been determined to be associated with low-moisture foods that were contaminated at low levels. Therefore, the expert committee carefully considered the qualitative microbiological analyses of RUFs and the contamination levels that could be inferred, and entered into an extended deliberation of dose-response modelling to find a path toward a reasonable approximation of the likely morbidity and mortality in SAM children that could be anticipated from consumption of RUFs contaminated at the estimated levels and observed frequency.The expert committee described three approaches that purchasers of RUFs might use to establish microbiological criteria to assure the safety of RUFs and to communicate to manufacturers their safety expectations. These approaches are: (i) reference to existing standards established for similar low-moisture foods; (ii) determining an acceptable increase in risk over the pre-existing baseline of illness from other sources of exposure; and (iii) process verification sampling using the moving window technique. The microbiological criteria derived by each of these approaches accomplish different purposes, and which is most appropriate is determined by the conditions of manufacture and use.

In 2020, the 43rd Session of the Codex Alimentarius Commission approved the “Development of Guidelines for the Safe Use and Reuse of Water in Food Production” proposed at the 51st Session of the Codex Committee on Food Hygiene. To support this work, JEMRA was asked to provide scientific advice on sector-specific applications and case studies for determining appropriate and fit-for-purpose microbiological criteria for water sourcing, use and reuse in fish and fishery products from primary production to retail. This report presented the outcome from the JEMRA meeting, which includes the: situation analysis concerning water use and reuse in the production and processing of fish and fishery products, analysis of case studies for different risk-based water use and reuse processing scenarios and species, water quality monitoring and the use of non-culture based microbiological methods, recommendations concerning the safety and quality of water used in fish production and processing, and critical research gaps and policy developments.

Spices and dried aromatic herbs impart flavour when added to food, and they may include many parts of the plant, including berries, flowers, leaves, roots and seeds. A number of different pathogens have been found in spices on the market, especially Salmonella spp., B. cereus and C. perfringens. There have also been several disease outbreaks associated with spices and dried aromatic herbs. An increased concern and attention to the safety of spices and dried aromatic herbs prompted, the Codex Committee on Food Hygiene (CCFH) to request FAO and WHO to undertake a risk assessment on microbiological hazards in these food commodities. An expert meeting of the FAO/WHO Joint Expert Meeting on Microbiological Risk Assessment (JEMRA) considered the global evidence on the burden of illness, prevalence and concentration of selected microbial hazards with respect to various spices and dried aromatic herbs, and interventions aimed at controlling them in these commodities. The experts developed the approach to rank the health risks related to the commodity-pathogen combinations, and assessed the performance of the existing Codex sampling plan for Salmonella against several contamination scenarios.

In 2019, following a request from the Codex Committee on Food Hygiene (CCFH), the Codex Alimentarius Committee (CAC) approved new work at its 42nd Session on the development of guidelines for the control of Shiga toxin-producing Escherichia coli (STEC) in leafy vegetables and in sprouts. The objective of the report was to evaluate commodity-specific interventions used at all stages of fresh fruit and vegetable production from primary production to post-harvest activities, transportation, point of sale and consumer use. Emphasis was placed on the identification and evaluation of interventions used throughout the world to reduce microbiological hazards of fresh fruits and vegetables that contribute to the risk of foodborne illnesses, taking into consideration their effectiveness, practicality and suitability. The expert committee addressed four subdivided commodity groups: 1) leafy vegetables and herbs, 2) berries and tropical fruits, 3) melons and tree fruits, and 4) seeded and root vegetables.

Microbiological Criteria have been used in food production and the food regulatory context for many years. While the food-specific aspects of microbiological criteria are well understood, the mathematical and statistical aspects are often less well appreciated, which hinders the consistent and appropriate application of microbiological criteria in the food industry. This document has been developed to begin redressing this situation. A particular aim of this document is to illustrate the important mathematical and statistical aspects of microbiological criteria, but with minimal statistical jargon, equations and mathematical details. It is hoped that the resulting document and support materials make this subject more accessible to a broad audience. This volume and others in this Microbiological Risk Assessment Series contain information that is useful to both food safety risk assessors and risk managers, the Codex Alimentarius Commission, governments and regulatory agencies, food producers and processers and other institutions and individuals with an interest in Microbiological Criteria. This volume in particular aims to support food business operators, quality assurance managers, food safety-policy makers and risk managers.