A survey in Ireland has found the majority of dried herbs and spices are safe but a small percentage may be contaminated with pathogens.

Between August and the end of November 2017, the Food Safety Authority of Ireland (FSAI), Environmental Health Service and Official Food Microbiology Laboratory Group of the Health Service Executive (HSE) investigated the microbiological safety of dried herbs and spices. The report is now available.

In total, 855 samples were collected, mostly at retail, by environmental health officers (EHOs) who were asked to find out if dried herbs and spices had been irradiated. A total of 64 were non-compliant. The survey showed only five samples had been decontaminated using irradiation. It is an approved treatment in Europe to control pathogens such as Salmonella in these products.

FSAI said the lack of irradiation highlights the importance of good hygienic conditions.

“Particularly, given that pathogenic microorganisms such as Salmonella can survive the drying process and survive on dehydrated foods for extended periods of time. If dried herbs and spices are not produced under hygienic conditions, they pose a risk of foodborne illness to the consumer as they frequently receive no further bactericidal treatment effective to eliminate pathogenic microorganisms of concern prior to consumption.”

Dried herbs and spices have low water activity that inhibit pathogens from growing but can allow some to survive. They are frequently eaten raw or used as ingredients in ready-to-eat foods (RTE) such as salads or as garnishes. Both items are not produced in large quantities in Ireland or other member states and are primarily imported into the EU from third countries.

Non-compliant findings
Samples were tested for Listeria monocytogenes and Listeria species, Salmonella, presumptive Bacillus cereus, and Shiga toxin-producing E. coli (STEC).

All 768 single and 73 batch samples tested for Listeria monocytogenes were satisfactory, as were the 164 samples analyzed for STEC.

Four samples were unsatisfactory for Salmonella out of 790 single samples. Salmonella Infantis was detected in dill and Salmonella with unknown serotypes were found in basil, ginger and dhaniya (coriander) powder.

The contaminated dried basil sample originated in Egypt and was imported via the United Kingdom, ground ginger came from Poland with raw materials from the Netherlands, dill was from Egypt and imported via Germany and Lithuania while the coriander was packed and imported from the UK but country of origin is unknown.

For presumptive Bacillus cereus, out of 828 single samples tested, 22 were unsatisfactory while 79 were borderline. Black pepper, turmeric and basil were among the main items to be unsatisfactory or borderline for the limits.

This high level of non-compliance may be due to Bacillus spores being naturally present on fresh herbs and spices which are then concentrated by the drying process, according to FSAI.

For hygiene indicators, five samples were unsatisfactory for E. coli from 748 single samples tested while 33 were unsatisfactory for Enterobacteriaceae out of 755 single samples. In addition, five E. coli and 87 Enterobacteriaceae samples were borderline.

Recommendations based on results
Dried herbs and spices can become contaminated with pathogens during growth, harvesting or processing and at retail level, if sold loose.

A survey by FSAI and HSE in 2004 on bacteriological and toxicological safety of dried herbs and spices found six of 647 samples were contaminated with Salmonella, while two single samples and one of 25 batch samples were unsatisfactory for presumptive Bacillus cereus.

In 2016, the EU Rapid alert System for Food and Feed (RASFF) portal listed 40 reports for 54 microorganisms in herbs and spices with Salmonella followed by E. coli being the most frequent. These pathogens were reported in herbs and spices such as fresh mint and parsley, dried parsley, mixed spices, ground cumin and coriander, peppermint, betel and curry leaves, chilli powder, fresh basil, perilla, and piper lolot. In this year, FSAI issued one food alert to recall spices due to Salmonella in coriander powder.

Between June and July 2017 an outbreak due to a rare serovar, Salmonella Adjame, involved 14 confirmed cases in the UK. Seven people reported being vegetarian. An implicated food was not found but it was suspected to be a fresh product bought from a grocer. There were two non-travel related Irish cases of Salmonella Adjame in 2017 but source of infection was never identified.

Recommendations based on the FSAI survey include businesses should source dried herbs and spices from reputable suppliers who can provide evidence of adequate hygiene controls during production and processing, firms adding dried herbs and spices to foods to be cooked should ensure food is cooled to 5 degrees C (41 degrees F) within two hours or consumed within four hours and these products should be sampled during routine official controls.