Cereals and grains at the top of microbiological risk ranking, according to FAO and WHO

Upon request of the Codex Committee on Food Hygiene (CCFH), the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) have recently published a report ranking the foods based on their microbiological risk.  

Cereals and grains have topped the list.  

These types of food are defined as low-moisture foods (LMF), being naturally low in moisture or produced from higher moisture foods through drying or dehydration processes. LMF have been considered safe for a long time because microorganisms cannot grow in them, however, it has been recently proven that bacteria can persist in these matrices and give rise to foodborne outbreaks.  

The ranking includes seven categories of LMF (i.e. cereals and grains; confections and snacks; dried fruits and vegetables; dried protein products; nuts and nut products; seeds for consumption; and spices and dried aromatic herbs) which have been evaluated based on burden of illness, production, consumption and international trade.  

The report covers the following microbial hazards: Bacillus cereus, Clostridium botulinum, Clostridium perfringens, Cronobacter, E. coli, Salmonella, Staphylococcus aureus, Listeria monocytogenes and Enterobacteriaceae.  

The data collection was done in 2014 and was analyzed till 2016.  

Cereals and grains reached the top of the ranking, scoring highly across all the criteria, especially for international trade and food consumption. The report highlights that this is not surprising, given the importance of the commodities/products in this category as staples in the global food supply.  

Dried protein products, which were ranked second, stood out in terms of burden of disease due to a couple of very large outbreaks associated with dried dairy products.  

The third place is occupied by spices, dried herbs and teas ranked third. Even if these products are usually consumed in small amounts, several large outbreaks associated with this food category have been recorded. This happened as there are many opportunities for contamination during the production and processing stages. Therefore, it does not surprise that FAO and WHO have published a specific report about risk assessment on microbiological hazards in spices and dried herbs.  

Nuts and nut products were ranked fourth, followed by confections and snacks; dried fruits and vegetables; and seeds for human consumption.  

In the report is stated that “this ranking exercise aimed to capture the situation from a global perspective and was driven by the ranking criteria and how they were weighted, and the expert panel itself which drove the process. The ranking is also a reflection of the available evidence and expert opinion at the time the work was undertaken. If undertaken at a regional or national level, or even at the global level again in the future, the inputs are likely to be different and therefore, the outcome may also be different”.