Fresh produce safety

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Feb 2017

The purpose of this statement is to provide the risk assessment background in relation to fresh produce including sprouted seeds and seeds for sprouting and to highlight current guides and codes of practice that have been developed for the food supply chain to minimise microbiological contamination of produce. Whilst produce is seen as an important source of nutrients and vitamins there have been a number of well-publicised food safety incidents associated with fresh produce. This has led to increased attention being paid to how the food safety hazards associated with raw foods should be effectively controlled and where possible reduced to a safe level.

Introduction

There have been a number of well publicised international food safety incidents associated with fresh produce over the last few years, most of which have arisen in the North American market. Recent North American incidents include Salmonellosis associated with Mexican-grown cucumbers and peppers, with mangoes and alfalfa sprouts, and Salmonella and Listeria monocytogenes linked with cantaloupe melons. In addition, over the past fifteen years there have been numerous North American E coli O157 outbreaks linked to fresh produce, and particularly to leafy vegetables. In the United Kingdom (UK) over the last six years there have been more than fourteen public recalls for presence of Salmonella or suspected Salmonella contamination of seeds1. The German/French E. coli O104 outbreak in May-June 2011 linked to a specific consignment of fenugreek seeds imported from Egypt caused 3,911 cases and 51 deaths. 2

 

The majority of incidents result from breaches of Good Agricultural Practices (GAP) or Good Handling Practices (GHP) in the field (e.g. use of non-composted manure, animals accessing crops or crop storage areas, or contaminated water being used for irrigation)3. The Health Protection Agency (HPA – now Public Health England, PHE) has publicly stated that issues arising in the UK are primarily linked to wholesale and imported produce, which is not subject to the level of growing and handling controls implemented by the UK’s retail and prepared produce supply chain.

Since produce is an important source of nutrients and vitamins, UK Government advice is to eat '5 portions a day' which relates to the World Health Organisation’s (WHO) recommendation of 400 grammes (5 x 80g) per day. Much produce is eaten raw, and whilst washing primarily removes soil, it will only reduce, but not eliminate, potential pathogenic organisms that may be present. It is therefore vital to minimise opportunities for contamination to occur during growing, handling and use. Owing to the existing controls in place in the UK retail pre-prepared salad sector, the Food Standards Agency (FSA) advised that salad labelled as washed and ready to eat ‘can be eaten straight out of the packet’ and does not require further washing by the consumer[1].

This approach recognises that effective produce safety management must begin in the field with the identification and control of potential microbiological food safety hazards at all stages in order to minimise harm to the consumer.

Hazard Reviews

The Joint FAO/WHO Expert Meetings on Microbiological Risk Assessment (JEMRA) began in 2000 as a result of a drive for international risk based scientific advice on microbiological food safety issues. Codex originally developed the Principles and Guidelines for the conduct of Microbiological Risk Assessment in 1999 4. This document, which defines microbiological risk assessment terminology and the general principles of microbiological risk assessment, has now been supplemented by a series of JEMRA guidelines. These include hazard characterisation for pathogens in food and water 5 and exposure assessment of microbiological hazards in food 6. Codex also revised its recommended international code of practice: general principles of food hygiene in 2003 7. This document states that a Hazard Analysis Critical Control Point (HACCP) based assessment should be undertaken and determines a number of pre-requisite procedures that need to be in place at primary production to ensure the safety of the food produced. In 2006, Codex agreed to progress the development of commodity-specific annexes to its Fresh Fruit and Vegetable Code.

This was progressed by the JEMRA risk prioritisation of fresh produce in terms of microbiological hazards that was produced by a meeting of experts in September 2007 8 and a FAO/WHO expert group May 2008 review of potential microbiological hazards and their control in the production of fresh leafy vegetables and herbs 9. That report noted that post-harvest treatments/handling will only reduce the number of microorganisms that may be present, but nothing apart from heat or irradiation is effective at eliminating them, which is not always appropriate. The report concluded that emphasis therefore needed to be on appropriate field standards. Appropriate grower knowledge of hazards, control of the growing environment (including the need for specific site assessment prior to cultivation, appropriate use of soil amendments and fertilisers and especially the role of composting) were identified in the report as being key together with full implementation of existing GAP standards. These and other key principles were in 2010 included in Annex I of the Codex Code of Good Hygienic Practice for Fresh Fruit and Vegetables 10 and therefore are recognised by the WTO. Codex is at the time of writing consolidating the various commodity-specific guidelines.

Standards

The European Chilled Food Federation in 1999 presented its Expert Group’s hazard minimisation review to the European Commission, which resulted in a Scientific Committee for Food produce risk assessment in 2001. To address the need for clear control guidance the Chilled Food Association (CFA) first published its Microbiological Guidance for Produce Suppliers to Chilled Food Manufacturers10 in 2002, publishing revisions in 2007 and 2016. This document provides information particularly in relation to produce that is to be minimally processed and eaten without being cooked regarding the main microbial food safety hazards, their control in the field and protocols on the assessment of decontamination efficacy and produce washing. In the UK “Guidance for food business operators on the hygienic sourcing, production and safe handling of ready to eat sprouts (FPC, 2012) was developed by an industry-FSA consortium, providing advice on reducing the risk of contamination16. Certain individual UK retailers have also developed their own GAP protocols that their produce suppliers, including overseas, are required to demonstrate compliance and undergoing monitoring and auditing. Documents such as Red Tractor Fresh Produce standards, and GlobalGAP12 standards have been expanded over recent years to incorporate microbiological food safety controls. GlobalGAP’s Harmonized Produce Safety Standard (HPSS) is an international auditable standard, which like GlobalGAP's Produce Safety Standard (PSS) only covers food safety and traceability. The Global Food Safety Initiative (GFSI)13 and the British Retail Consortium (BRC) Global Standards14 are generic standards applying to factory hygiene and post-harvest control of potential microbiological contamination. The FSA and Horticulture Development Company in 2010 produced a factsheet15 and web-based risk assessment tools15 for growers, that deal with water use, manure/composted manure inputs and worker hygiene.

Good Agricultural Practice

GAP is the result of the application of HACCP principles for on-farm processes, including identifying the measures required to eliminate physical, chemical and microbial contamination risks and, where this is not possible, reduce them to an acceptable level. Key control elements include:

·       Appropriate growing location selection, e.g. away from wildlife, livestock, low flood risk

·       Regular microbiological assessment of irrigation water with treatment before use as appropriate to the crop;

·       Controls on the use of organic fertilisers, especially those which contain manures – raw farmyard manure usage on raw ready to eat crops being prohibited in the CFA guidelines;

·       Hand washing and toilet facilities provided for field workers;

·       Hygiene training of harvest staff;

·       Washing and disinfection of harvesting equipment (e.g. knives, automatic harvesters);

·       Hygienic facilities for harvesting/handling/chilling/processing and despatch;

·       Floating and/or washing under controlled conditions to remove soil and reduce microbial loading with water of a suitable microbiological standard;

·       Temperature control to minimise microbiological growth;

·       Allocation of appropriate shelf life to minimise opportunity for microbial growth;

·       Appropriate crop protection and chemical controls to minimise the risk of contamination and

·       Effective control of potential physical contaminants through the use of pre-requisite programmed which are monitored and verified.

The whole produce supply chain needs to be aware of the potential hazards associated with fresh produce, particularly that to be eaten raw or minimally processed, and implement monitored controls that are demonstrably effective in reducing the likelihood of the occurrence of hazards. Existing GAP focused on microbiological control measures should be taken up by all ready to eat produce producers.

List of acronyms

BRC                  British Retail Consortium

CFA                  Chilled Food Association

FAO                 Food Agriculture Organisation (United Nations)

FPC                  Fresh Produce Consortium

FSA                  Food Standards Agency

GAP                 Good Agricultural Practice

GFSI                 Global Food Safety Initiative

GHP                 Good Handling Practice (sometimes called Good Hygienic Practice)

HACCP             Hazard Analysis Critical Control Point

HPA                 Health Protection Agency

HPss                Harmonized Produce Safety Standard (GlobalGAP)

JEMRA              Joint FAO/WHO Expert meeting on Microbiological Risk Assessment

PHE                  Public Health England

UK                   United Kingdom

WHO                World Health Organisation

References
  1. Food Standards Agency Website – Food Alerts: http://www.food.gov.uk/enforcement/alerts/ (accessed 29/3/16)

  2. Scientific Report of EFSA. Shiga Toxin-Producing E. coli (STEC) O104:H4 2011 Outbreaks In Europe: Taking Stock (2011). European Food Safety Authority (EFSA), Parma, Italy.http://www.efsa.europa.eu/en/efsajournal/doc/2390.pdf (accessed 13/2/16)
  3. Food Standards Agency Project B17007: A review of the published literature describing foodborne illness outbreaks associated with ready to eat fresh produce and an overview of current UK fresh produce farming practices (2011): http://www.food.gov.uk/science/research/foodborneillness/b17programme/b17projlist/b17007 (accessed 13/2/16)
  4. Codex Principles and Guidelines for the conduct of Microbiological Risk Assessment (1999) Accessible at: ftp://ftp.fao.org/es/esn/jemra/CAC_GL30.pdf (accessed 13/2/16)
  5. Hazard characterization for pathogens in food and water: Guidelines Microbiological Risk Assessment Series 3 - FAO/WHO (2004) (ISBN 92-5-104940-8) Accessible at: ftp://ftp.fao.org/docrep/fao/006/y4666E/y4666E00.pdf (accessed 13/2/16)
  6. Exposure assessment of microbiological hazards in food: Guidelines Microbiological Risk Assessment Series 7 - FAO/WHO (2008) (ISBN 92-5-105422-2) Accessible at http://apps.who.int//iris/bitstream/10665/43389/1/9241546891_eng.pdf?ua=1 (accessed 13/2/16)
  7. Recommended international code of practice: general principles of food - CAC/RCP 1-1969, Rev. 4-2003. http://www.fao.org/fao-who-codexalimentarius/download/standards/23/CXP_001e.pdf (accessed 13/2/16)
  8. Microbiological hazards in fresh fruits and vegetables: Meeting report Microbiological Risk Assessment Series 14, FAO/WHO (2008) (ISBN 978-92-4-156378-9). Accessible at: http://www.fao.org/3/a-i0452e.pdf (accessed 13/2/16)
  9. Codex Code of Good Hygienic Practice for Fresh Fruit and Vegetables (2003), CAC/RCP 53-2003, http://www.fao.org/fao-who-codexalimentarius/download/standards/10200/CXP_053e_2013.pdf (accessed 13/2/16)
  10. Microbiological Guidance for Produce Suppliers to Chilled Food Manufacturers (Micro Guidance for Growers). Available from: http://www.chilledfood.org/product-category/all_resources/cfa-guidelines (accessed 13/2/16)
  11. GlobalGAP Integrated Farm Assurance. Fruit and Vegetable Standards. Accessible at: http://www.globalgap.org (accessed 13/2/16)
  12. Global Food Safety Initiative Accessible at: http://www.mygfsi.com (accessed 13/2/16)
  13. British Retail Consortium Global Standard for Food Safety. Accessible at: http://www.brc.org.uk/standards/ (accessed 13/2/16)
  14. Food Standards Agency and Horticultural Development Company. Monitoring microbial food safety of fresh produce (2010). Accessible at: http:/ /www.food.gov.uk/sites/default/files/multimedia/pdfs/microbial.pdf   (accessed 29/3/15)
  15. Guidance for food business operators on the hygienic sourcing, production and safe handling of ready to eat sprouts (2012). Fresh Produce Consortium. Accessible at: http://www.freshproduce.org.uk/services/fpc-publications/ (accessed 13/2/16)
Further reading

Institute of Food Science and Technology Information Statement:Verocytotoxin-producing E.coli Food Poisoning and its Prevention, 2012, IFST.

Outbreaks attributed to fresh leafy vegetables, United States, 1973–2012. Herman, K.M. et al, Epidemiology and Infection / Volume 143 / Issue 14 / October 2015, pp 3011-3021  http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=9947150&fileId=S0950268815000047 (accessed 29/3/16)

Sprouts Associated Outbreaks. http://www.foodsafetynews.com/files/2016/02/Sprout-associated-outbreaks-2-24-161.pdf  (accessed 2/3/16)

 

The Institute of Food Science & Technology has authorised the publication of the following updated Information Statement on Fresh Produce Safety, dated Feb 2017, replacing that of March 2013 [and the first edition in March 2011]. These Information Statements were prepared by Kaarin Goodburn MBE and Dr Louise Manning. This Information Statement was approved by the IFST Scientific Committee.

 

The Institute takes every possible care in compiling, preparing and issuing the information contained in IFST Information Statements, but can accept no liability whatsoever in connection with them. Nothing in them should be construed as absolving anyone from complying with legal requirements. They are provided for general information and guidance and to express expert professional interpretation and opinion, on important food-related issues.

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