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FOOD SAFETY AUTHORITY OF IRELAND National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs (19NS6) MONITORING & SURVEILLANCE SERIES 2022 MICROBIOLOGY  FOOD SAFETY AUTHORITY OF IRELAND National Microbiological Survey and Consumer Habits in Relation to Frozen Vegetables, Fruits and Herbs Published by: Food Safety Authority of Ireland The Exchange, George’s Dock, IFSC, Dublin 1, D01 P2V6 T +353 1 817 1300 E [email protected] www.fsai.ie © FSAI 2022 Applications for reproduction should be made to the FSAI Information Unit ISBN: 978-1-910348-54-3  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 1 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY Contents ACKNOWLEDGEMENTS ...................................................................................................3 SUMMARY ..........................................................................................................................5 INTRODUCTION .................................................................................................................9 AIMS OF THE MICROBIOLOGICAL AND CONSUMER SURVEYS................................11 NATIONAL MICROBIOLOGICAL SURVEY METHODS ..................................................12 CONSUMER SURVEY METHODS ...................................................................................16 NATIONAL MICROBIOLOGICAL SURVEY RESULTS AND DISCUSSION....................18 LISTERIA MONOCYTOGENES ......................................................................................................................20 L. MONOCYTOGENES TYPING AND CHARACTERISATION......................................................................24 LISTERIA SPP. ................................................................................................................................................27 SALMONELLA.................................................................................................................................................31 E. COLI.............................................................................................................................................................32 CONSUMER SURVEY RESULTS AND DISCUSSION.....................................................34 CONSUMPTION OF UNCOOKED FROZEN VEGETABLES, FRUITS AND HERBS....................................37 MAIN WAYS UNCOOKED FROZEN VEGETABLES, FRUITS AND HERBS ARE CONSUMED.................39 GROWTH OF L. MONOCYTOGENES IN THAWED FROZEN VEGETABLES, FRUITS AND HERBS........41 CONSUMERS’ FOOD PREPARATION HABITS ............................................................................................43 CONSUMER AWARENESS OF FOODBORNE LISTERIOSIS ......................................................................44 CONSUMER AWARENESS OF PREVIOUS FOODBORNE OUTBREAKS..................................................46 CONCLUSIONS ................................................................................................................48 RECOMMENDATIONS .....................................................................................................54 REFERENCES ..................................................................................................................55 APPENDICES ..................................................................................................................57  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 1 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY List of Figures Figure 1 The demographics of consumers interviewed for the consumer survey to determine how adults on the island of Ireland prepare and consume frozen vegetables, fruits and herbs............. 17 Figure 2 Percentage breakdown of frozen vegetable, fruit and herb samples (n=907) collected, by food chain stage.............................................................................................................................. 19 Figure 3 Product descriptions of RTE and non-RTE frozen vegetable, fruit and herb samples analysed for the survey................................................................................................................... 19 Figure 4 Product descriptions of RTE (n=6) and non-RTE (n=21) survey samples that were contaminated with L. monocytogenes............................................................................................. 23 Figure 5 Distribution of clonal complexes (CC MLST) .................................................................... 25 Figure 6 Minimum spanning tree (MST) showing cluster analysis of the core genome multi-locus sequence typing (cgMLST) ............................................................................................................. 26 Figure 7 Product descriptions of RTE (n=7) and non-RTE (n=29) survey samples that were contaminated with Listeria spp........................................................................................................ 29 Figure 8 Product descriptions of survey samples (n=7) that were contaminated with both L. monocytogenes and Listeria spp. ................................................................................................... 30 Figure 9 The types of frozen vegetables, fruits and herbs most frequently consumed by adults surveyed on the island of Ireland (n=680)....................................................................................... 35 Figure 10 The types and percentage of frozen vegetables, fruits and/or herbs that adults on the island of Ireland said they eat uncooked......................................................................................... 37  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 2 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY List of Tables Table 1 Target genes for L. monocytogenes for typing and characterisation ................................. 15 Table 2 Correlation between serological and molecular serotyping ............................................... 15 Table 3 The prevalence of Listeria monocytogenes in frozen vegetables, fruits and herbs ........... 22 Table 4 Sample description of frozen vegetable, fruit and herb samples with L. monocytogenes detected in 25 g, along with their molecular characterisation results.............................................. 24 Table 5 The prevalence of Listeria spp. in frozen vegetables, fruits and herbs.............................. 28 Table 6 The prevalence of Salmonella in frozen vegetables, fruits and herbs ............................... 31 Table 7 The prevalence of E. coli in frozen vegetables, fruits and herbs ....................................... 33 Table 8 The number of respondents to each question asked as part of the consumer survey....... 36 Table 9 The ways in which the top five frozen fruits eaten uncooked are used by consumers on the island of Ireland............................................................................................................................... 38 Table 10 The percentage of certain frozen vegetables, fruits and herbs normally consumed by adults in Ireland, compared with those who said they would consume this frozen food uncooked 40 Table 11 The top five ways frozen vegetables are eaten uncooked by consumers in Ireland........ 40 Table 12 Consumer perception as to whether certain frozen vegetables, fruits and herbs require cooking prior to eating..................................................................................................................... 45 Table 13 The percentage of adults on the island of Ireland who prepare food for at least one of the vulnerable groups shown below...................................................................................................... 46 Table 14 Consumer awareness of the European 2018 listeriosis outbreak associated with frozen vegetables and the risk of foodborne illness related to consuming uncooked imported frozen berries............................................................................................................................................. 47  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 3 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY Acknowledgements The FSAI acknowledges and thanks safefood for participating in this survey and for funding the consumer research survey on frozen food consumption. It would also like to thank those who participated in the national microbiological survey, including the Environmental Health Officers (EHOs); the laboratory staff of the seven HSE Official Food Microbiology Laboratories (OFMLs);1 the Department of Agriculture, Food and the Marine (DAFM) National Reference Laboratory (NRL) for L. moncytogenes, Backweston, Co Kildare; and the National Salmonella, Shigella and Listeria Reference Laboratory (NSSLRL), University Hospital Galway. 1 (i) Public Health Laboratory, Limerick; (ii) Public Health Laboratory, Sligo General Hospital, Sligo; (iii) Public Health Laboratory, Waterford Regional Hospital, Waterford; (iv) Public Analyst’s Laboratory, Sir Patrick Dun’s Hospital, Grand Canal Street, Dublin; (v) Public Health Microbiology Laboratory, St Finbarr’s Hospital, Cork; (vi) Public Health Microbiology Laboratory, Cherry Orchard Hospital, Dublin; and (vii) Public Health Microbiology Laboratory, University College Hospital Galway  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 4 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY Glossary aw water activity CC clonal complex CC MLST clonal complex multi-locus sequence typing CDC Centers for Disease Control and Prevention (United States) cgMLST core genome multi-locus sequence typing CE Calculation Engine cfu colony forming unit CSO Central Statistics Office DAFM Department of Agriculture, Food and the Marine ECDC European Centre for Disease Prevention and Control EFSA European Food Safety Authority EHO Environmental Health Officer EHS Environmental Health Service EN ISO European Standard International Organization for Standardization FSAI Food Safety Authority of Ireland HSE Health Service Executive INAB Irish National Accreditation Board MST minimum spanning tree n number of sample units non-RTE non-ready-to-eat NRL National Reference Laboratory OFMLs Official Food Microbiology Laboratories PCR polymerase chain reaction PROFEL European Association of Fruit and Vegetable Processors RASFF Rapid Alert System for Food and Feed RTE ready-to-eat WGS whole genome sequencing  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 5 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY Summary Following a multi-country listeriosis outbreak in Europe traced to the consumption of uncooked non-ready-to-eat (non-RTE) frozen sweetcorn and possibly to other frozen vegetables (ECDC- EFSA, 2018), a national microbiological survey was undertaken between August and November 2019 by the Food Safety Authority of Ireland (FSAI) in conjunction with the Environmental Health Service (EHS) and the Health Service Executive (HSE) Official Food Microbiology Laboratories (OFMLs) to gain a better understanding of the microbiological quality of ready-to-eat (RTE) and non-RTE frozen vegetables, fruits and herbs placed on the market in Ireland. To complement the results of the national microbiological survey, a consumer survey was undertaken in conjunction with the all-island food safety promotion board, safefood, between January and March 2020 to further understand the consumption habits of adults living on the island of Ireland in relation to uncooked RTE and non-RTE frozen vegetables, fruits and herbs. The results of both the FSAI national microbiological survey and the safefood consumer survey are co- published in this report. National microbiological survey Between 1 August and 30 November 2019, 907 samples of frozen vegetables, fruits and herbs were collected by Environmental Health Officers (EHOs) for the national microbiological survey. Most of these were single samples (n=882). Five batch samples, each comprising five individual sample units, were taken at the manufacturing and packing stage (n=25 samples in total). Five hundred and one of the samples collected were RTE and 366 samples were non-RTE. The RTE status was not provided for 40 of the samples collected. The samples were assessed for the microbiological parameters of Listeria monocytogenes, Salmonella, Listeria spp. and Escherichia coli. The L. monocytogenes detection method was used to test 9062 samples, while the L. monocytogenes enumeration method was used to test 907 samples. Of the 906 samples tested for L. monocytogenes using the detection method, 3% (n=27) were positive, the majority of which were non-RTE frozen vegetables (n=21). L. monocytogenes was detected in four samples of RTE frozen fruits and two samples of RTE frozen vegetables. The L. monocytogenes results of 907 2 The L. monocytogenes detection method was not used to test one sample of RTE frozen sour cherries. The same sample of RTE frozen sour cherries was tested using the L. monocytogenes enumeration method and had a test result of <10 cfu/g.  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 6 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY survey samples tested using the enumeration method showed that all were compliant with the 100 cfu/g microbiological criterion limit set for L. monocytogenes in RTE food placed on the market in Commission Regulation (EC) No 2073/2005, as amended. L. monocytogenes was below the limit of detection (<10 cfu/g) for the majority of samples, apart from three samples, which were non-RTE frozen petit pois, non-RTE frozen diced onion, and frozen chopped basil (RTE status not stated), all of which had 10 cfu/g L. monocytogenes present. Of the 8283 survey samples tested for Listeria spp. using the detection method, 4.5% (n=37) were positive. The enumeration method for Listeria spp. was used on 907 samples. The test result for the majority of these samples (n=904, 99.7%) was <10 cfu/g Listeria spp., while 10 cfu/g was present in two samples of non-RTE frozen sweetcorn and one sample of frozen chopped basil (RTE status not stated). The same sample of frozen chopped basil had 10 cfu/g L. monocytogenes present in it. None of the survey samples tested in the national microbiological survey were found to be contaminated with Salmonella (n=885)4. The presence of E. coli as a hygiene indicator was assessed in a total of 8875 frozen vegetable, fruit and herb samples. Ten of the samples tested (1.1%) were contaminated with E. coli at levels of between 20 and 100 cfu/g; two of these samples were RTE frozen vegetables. There were two non-RTE samples of frozen spinach with E. coli levels of 1100 cfu/g and 570 cfu/g present. The isolates confirmed as L. monocytogenes (n=27) were sent for serotyping using molecular typing methods and genomic characterisation by whole genome sequencing (WGS) to the National Reference Laboratory (NRL) for L. monocytogenes based in the Department of Agriculture, Food and the Marine (DAFM). Most of the isolates were in the molecular serogroup IIa (n=23), while three of them were in the molecular serogroup IVb and one was in the molecular serogroup IIb. The results showed diversity in the strains, as 13 different clonal complex (CC) groups were identified using WGS. CC8 was the predominant type, accounting for 26% (n=7) of the L. monocytogenes isolates cultured in the survey. 3 Seventy-eight samples were not tested for Listeria spp. using the detection method because the OFML that received these samples was not accredited for the test. The detection method for Listeria spp. was also not used on one sample of RTE frozen sour cherries. 4 Analysis of Salmonella spp. was carried out on the first sample unit only of five batch samples collected (each consisting of five individual sample units). The Salmonella spp. test was also not carried out on two single samples, but all other survey parameters were assessed in these samples. 5 Analysis of E. coli was carried out on the first sample unit only of five batch samples collected (each consisting of five individual sample units).  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 7 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY The minimum spanning tree (MST)6 visualised four small clusters, three of which contained isolates cultured from frozen sweetcorn samples, along with samples of frozen mixed vegetables, fruit smoothie mix and cherries (Clusters A, B and C, respectively). Cluster D comprised two isolates, both cultured from petit pois samples. Consumer survey The total number of interviews achieved for the consumer survey on the island of Ireland was 815 (502 participants were based in Ireland and 313 were based in Northern Ireland). The consumer survey found that 80% (n=650) of the survey participants said they consume frozen vegetables, 40% (n=325) said they consume frozen fruits, and 13% (n=103) said they consume frozen herbs. Of the 678 adults on the island of Ireland who responded to the question on consuming uncooked frozen vegetables, fruits and/or herbs, 68% (n=460) said they do not consume any uncooked frozen foods. Some of the respondents consumed more than one type of frozen vegetables, fruits and/or herbs uncooked. The survey responses showed that frozen fruits such as strawberries (n=101), blueberries (n=79), raspberries (n=78), and mixed berries (n=68) were the most likely to be consumed uncooked. The main way in which frozen fruits were consumed uncooked was in a dessert or in a smoothie. A smaller number of survey participants said they would normally consume uncooked frozen vegetables such as sweetcorn (n=21), carrots (n=21), peas (n=14), peppers (n=13), and spinach (n=12). The main way in which consumers would use these uncooked frozen vegetables was in a salad or as a garnish. Risk of listeriosis When the results of the national microbiological survey were correlated with the responses given by consumers in the survey on their consumption habits in relation to frozen vegetables, fruits and herbs, they showed that a small proportion of non-RTE frozen vegetables – which a small number of consumers say they regularly consume uncooked (i.e. sweetcorn, petit pois/garden peas, mixed vegetables, broccoli, peppers, and onion) – were contaminated with low levels of L. monocytogenes. The levels found in the majority of these samples were detected in 25 g at <10 cfu/g, while 10 cfu/g was found in non-RTE frozen petit pois (n=1), non-RTE frozen diced onion 6 The genomic differences or similarities between all of the isolates characterised by WGS are represented by a dendrogram called the MST. A cluster is defined as isolates with ≤7 allele difference between their core genome.  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 8 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY (n=1), and frozen chopped basil (n=1; RTE status not designated). If these low levels were present at the point of consumption of uncooked frozen non-RTE vegetables, the risk posed to consumers who are in good health should be minimal. However, the risk could be higher for consumers who are immunocompromised, or if consumer preparation and handling practices allow any of the L. monocytogenes contamination present in the non-RTE frozen vegetables to increase at the point of consumption to levels high enough to potentially cause listeriosis (i.e. >100 cfu/g). In order to avoid future food incidents similar to the European listeriosis outbreak between 2015- 2018, manufacturers of frozen vegetables, fruits and herbs are advised to follow the hygiene guidelines published by PROFEL (the European Association of Fruit and Vegetable Processors) for the control of L. monocytogenes in the production of quick-frozen vegetables (PROFEL, 2020), and to also follow the recommendations made by the European Food Safety Authority Panel on Biological Hazards (EFSA BIOHAZ Panel) in its Scientific Opinion on the public health risk posed by Listeria monocytogenes in frozen fruit and vegetables, including herbs, blanched during processing (EFSA BIOHAZ Panel, 2020). Public health agencies providing food safety advice should encourage consumers to follow the manufacturer’s instructions, as printed on the packaging, when preparing frozen vegetables, fruits and herbs.  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 9 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY Introduction Trends in healthy eating, especially those featured on social media, encourage consumers to increase their consumption of vegetables, fruits and herbs in their daily diets by incorporating them into smoothies and salads. The desire to eat more healthily, reduce food waste and save time when preparing food means that frozen vegetables, fruits and herbs are seen as a convenient choice of ingredient. In response, frozen food manufacturers and retailers have substantially increased the range of frozen vegetables, fruits and herbs available to consumers (Bord Bia, 2019). Some of these frozen vegetables, fruits and herbs are specifically labelled as RTE, or do not have cooking instructions on their packaging, and are therefore considered RTE by default (e.g. frozen fruits intended for use in smoothies, or frozen herbs added as a garnish). However, others, and frozen vegetables in particular, are considered by the manufacturer as non-ready-to- eat (non-RTE). According to the Food Safety Authority of Ireland (FSAI) Guidance Note 27, non- RTE foods have cooking instructions printed on the packaging and do not indicate anywhere on the packaging that they can be consumed without cooking (FSAI, 2014). Two listeriosis outbreaks traced to consumption of frozen vegetables (particularly frozen sweetcorn) in Europe (ECDC-EFSA, 2018) and the United States of America (USA) (CDC, 2016) show that eating uncooked non-RTE frozen produce can represent a serious risk to human health. The 2015–2018 European outbreak resulted in 53 listeriosis cases, with 10 fatalities, and affected consumers in five European countries (ECDC-EFSA, 2018; EFSA BIOHAZ Panel, 2020). Some of the frozen vegetables implicated in this outbreak were placed on the market in Ireland. In July 2018, the FSAI issued a recall of the implicated batches (FSAI, 2018a). Some of the people who were ill with listeriosis during these outbreaks indicated that they had eaten non-RTE frozen vegetables without following the cooking instructions on the packaging (e.g. by adding them uncooked to salads and smoothies). From the food histories collected during both outbreaks, it would appear that some consumers do not perceive eating uncooked non-RTE frozen vegetables as a potential source of foodborne illness. However, compared with the production of fresh produce, there is an increased likelihood of a microbiological contamination event happening during the frozen vegetables, fruits and herbs manufacturing process. This is due to the potential for environmental contamination with L. monocytogenes in the manufacturing facility (EFSA BIOHAZ Panel, 2020). WGS of the L. monocytogenes strain involved in the 2015–2018 European outbreak showed that the outbreak strain persisted in the environment of the implicated frozen vegetable manufacturing facility in Hungary over many years despite cleaning and disinfection procedures carried out by the food business (ECDC-EFSA, 2018; EFSA BIOHAZ Panel, 2020).  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 10 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY A search of the Rapid Alert System for Food and Feed (RASFF) shows that microbiological contamination of frozen vegetables, fruits and herbs with L. monocytogenes, Salmonella, hepatitis A virus and norovirus has been notified occasionally in previous years (Appendix 1). While no specific outbreak of listeriosis has been attributed to frozen fruits and frozen herbs, many of these products are processed in the same facility as frozen vegetables, meaning that they could also be a potential source of foodborne illness if L. monocytogenes is persistent in the processing environment. Frozen fruit was recalled as part of the US outbreak as it was processed in the same facility (CDC, 2016). The listeriosis risk can be addressed by consumers ensuring that they cook non-RTE frozen vegetables, fruits and herbs prior to consumption, as per the cooking instructions on the packaging. However, the popularity among Irish consumers of eating uncooked non-RTE frozen vegetables, fruits and herbs in smoothies and salads is unknown. Information on consumer behaviour in relation to consumption of frozen food would be beneficial, in order to assess the risk of listeriosis from eating contaminated uncooked frozen vegetables, fruits and herbs in salads and smoothies. To better understand consumer behaviour in relation to this, a safefood-funded consumer research survey on frozen food consumption was conducted. The results of the safefood consumer survey are co-published in this report to complement the results of the microbiological data generated by the national microbiological survey. The consumer survey provides vital information on consumer attitudes and behaviours on the consumption of cooked and uncooked frozen vegetables, fruits and herbs by adults on the island of Ireland. The consumer survey was also used as an opportunity to ask participants about their general knowledge regarding the risk of listeriosis from consuming RTE food. Information from this consumer survey will be used as a future basis for delivering targeted food safety advice to limit the risks of listeriosis in those who are particularly vulnerable. Additionally, the consumer survey provided a good opportunity to gauge public awareness of previous foodborne outbreaks of norovirus and hepatitis A virus linked to the consumption of uncooked imported frozen berries across Europe since 2013. As a result of these outbreaks, the FSAI recommends boiling imported frozen berries for 1 minute prior to consumption (FSAI, 2020b). Consumption of uncooked frozen berries and frozen vegetables thawed and eaten without thorough cooking are listed as a high-risk food choice for people who are particularly vulnerable to foodborne illness in the FSAI factsheet Reduce the Risk of Food Poisoning: Information for People who are Particularly Vulnerable (FSAI, 2018b).  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 11 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY Aims of the microbiological and consumer surveys Given the limited data available on the level of microbiological contamination in frozen vegetables, fruits and herbs placed on the market in Ireland and the potential unknown risk to public health, the FSAI in conjunction with the Environmental Health Service (EHS) and the Health Service Executive (HSE) Official Food Microbiological Laboratories (OFMLs), conducted a national microbiological survey in 2019 to investigate the microbiological quality of RTE and non-RTE frozen vegetables, fruit and herbs. To generate information on consumption habits in Ireland in relation to RTE and non-RTE frozen vegetables, fruits and herbs, a consumer survey was conducted by safefood to complement the results of the national microbiological survey. The consumer survey gathered information on the popularity of RTE and non-RTE frozen vegetables, fruits and herbs among consumers, together with information on their consumption habits in relation to uncooked non-RTE frozen vegetables, fruits and herbs. A blank copy of the research questionnaire to assess consumer attitudes on frozen food preparation and consumption is provided in Appendix 2. The specific aims of the national microbiological survey were to: • Determine the microbiological safety of RTE frozen vegetables, fruits and herbs placed on the market in Ireland, and • Generate useful prevalence data on pathogens through the monitoring and surveillance of non-RTE frozen vegetables, fruits and herbs placed on the market in Ireland. The specific aims of the consumer survey were to: • Generate consumer behaviour data on the consumption of uncooked non-RTE frozen vegetables, fruits and herbs on the island of Ireland • Gauge general consumer awareness of the risk of listeriosis from consuming RTE food • Gauge general consumer awareness of the risks of foodborne illness due to possible norovirus and hepatitis A virus contamination in imported frozen berries, and • Generate information to determine if a consumer awareness campaign regarding the possible risk of foodborne illness from eating uncooked non-RTE frozen vegetables, fruits and herbs is necessary.  National Microbiological Survey and Consumer Habits in relation to Frozen Vegetables, Fruits and Herbs FOOD SAFETY AUTHORITY OF IRELAND Page 12 MONITORING & SURVEILLANCE SERIES | MICROBIOLOGY National microbiological survey methods Sample collection Between 1 August and 30 November 2019, EHOs from the HSE collected 882 single samples of RTE and non-RTE frozen vegetables, fruit and herbs from the following establishments: • Wholesalers, distributors, and transporters • Caterers • Retailers such as supermarkets, corner shops, convenience stores, market stalls, health food shops, petrol station forecourts, etc. Five batch samples, each comprising five individual sample units, were taken at the manufacturing and packing stage (n=25 samples in total). All samples were fully enclosed in sealed packaging, so that in the event of an unsatisfactory test result, it would be clear that the product was contaminated at the manufacturing/packing stage and not during the distribution or retail stages. RTE status The RTE status of the frozen vegetables, fruits and herbs sampled for the national microbiological survey was determined by evaluating the product label at the time of sampling, in order to establish whether the sample was RTE or non-RTE; this was done by following the guidance set out in the decision tree in Figure 1, FSAI Guidance Note 27 (FSAI, 2014, p. 32). Survey samples were considered RTE if they were not labelled with cooking instructions, and/or if the packaging indicated anywhere that the frozen vegetables, fruits or herbs could be eaten without cooking (e.g. if there was a serving suggestion or directions for use printed on the packaging which indicated that the product could be added directly to smoothies or salads, or used as a garnish without cooking). This information was entered into the National Sample Submission Form at the time of sampling by the sampling officer. Sampling officers were instructed not to collect samples of frozen vegetables, fruits or herbs if it was considered that the consumer was most likely to always cook the product based on the presentation and marketing on the packaging label, e.g. the use of the words “oven”, “steam”, or “stir-fry” on the front of the pack.