Industry Information Session: Implementation of the 2011 Health Canada "Policy on Listeria monocytogenes in Ready-to-Eat Foods"

Outline of the Presentation

Topic 1: Purpose of the Listeria Policy Revision

Revised Listeria Policy

Effective Date: April 1, 2011

The Listeria Policy was developed and revised by Health Canada (HC), in consultation with the Canadian Food Inspection Agency (CFIA) and the Public Health Agency of Canada (PHAC).

Purpose and Scope of the Listeria Policy

(Section 2 of the Listeria Policy)

  • Protect the health of Canadians
  • Serve as a tool to assist industry to comply with food safety regulatory requirements
  • Provide recommendations to industry on the verification, monitoring and control of Listeria in the production of ready-to-eat (RTE) food
  • Provide guidance to regulatory authorities on oversight of RTE food production and compliance activities if the food is contaminated with Listeria monocytogenes (Lm)

Events Leading Up to the Policy Revision

  • The Listeria Policy was last revised in July of 2004.
  • The Codex Alimentarius Commission adopted the Guidelines on the Application of General Principles of Food Hygiene to the Control of Listeria monocytogenes in Ready-to-Eat Foods (CAC/GL 61 – 2007).
  • Two large multi-provincial listeriosis outbreaks: deli meat produced in Ontario resulting in 23 deaths, cheese produced in Quebec resulting in 2 deaths.
  • Prime Minister Harper appoints Ms. Weatherill to conduct an independent investigation. The Weatherill report recommendation #11: "Health Canada should complete the revision of its 2004 Listeria Policy, by no later than March 2010."

Goals of the Revised Listeria Policy

(Section 1 of the Listeria Policy

  • Enhance the verification and control of Listeria spp. in the food processing environment.
  • Permit early identification of any potential contamination in the plant environment.
  • Increase the ability to identify and mitigate the risk of Lm contamination in the finished product.

These actions will provide early warning and permit the appropriate interventions to protect consumers.

Key Policy Revisions

(Section 1 of the Listeria Policy)

End-product compliance criteria: Similar to International Codex Alimentarius Commission standards, the revised Listeria Policy contains new compliance criteria for end-products tested for the presence of Lm.

RTE food categories: Definitions of RTE foods in which growth of Lmcan or cannot occur have been modified and/or developed (i.e. new definition of Categories 1, 2A and 2B).

Compliance action decision tree: Decision tree related to compliance action, including environmental testing for Listeria spp. and end-product testing for Lm, has been modified to include more details on sampling.

Environmental monitoring program: Environmental monitoring program should be included in all plants producing RTE foods, as defined by the Listeria Policy.

Post-lethality treatments/growth inhibitors: The use of post-lethality treatments and/or Lm growth inhibitors is encouraged.

Outreach: Outreach with federal/provincial/territorial community to increase awareness of the risks of listeriosis and to provide guidance on how to reduce the risks.

Topic 2: Characteristics of Listeria monocytogenes

Listeria

Genus Listeria (family Listeriaceae)

6 most common species:

  • Listeria monocytogenes
  • Listeria ivanovii
  • Listeria innocua
  • Listeria grayi
  • Listeria welshimeri
  • Listeria seeligeri

When the term Listeria spp. is used, it refers to any and/or all of the Listeria species including Lm.

Listeria monocytogenes

(Section 4 of the Listeria Policy)

General Characteristics:

  • Size (1 – 2 µm x 0.5 µm)
  • Gram-positive bacterium, rod-shaped, non-spore forming
  • Can grow at wide pH range (4.4 or greater), water activity (aw) ≥ 0.92
  • Facultative anaerobe
  • Measured in colony-forming units (CFU) per gram (g) or per millilitre (ml)

Unique Characteristics:

  • Widely present in the natural and processing environments (e.g., soil, water, drains, ventilation)
  • Grows in food stored under refrigerated temperatures (-0.4 and 45 °C)
  • Pathogenic to humans (causes foodborne illness - listeriosis)

What is Listeriosis?

(Section 4 and 5 of the Listeria Policy)

  • A rare and serious disease
  • Symptoms may include vomiting, nausea, diarrhea, severe headache, constipation and persistent fever
  • Serious infections of Lm may cause miscarriages or stillbirths in pregnant women and lead to meningitis, septicaemia and death in high risk populations (e.g., the elderly or immunocompromised)

Risk Factors for Foodborn Listeriosis

(Section 4 and 5 of the Listeria Policy)

  • Presence of Lm in the food
  • Potential for growth of Lm in the food
  • Storage temperature and duration
  • Amount and frequency of consumption of a food contaminated with Lm
  • Host susceptibility (e.g., high-risk populations)

Topic 3: Roles and Responsibilities

In relation to the Listeria Policy, the following roles and responsibilities are outlined in the Policy:

  • RTE Food Industry
  • Government
  • Consumers

RTE Food Industry - Processors and Importers

(Section 3 of the Listeria Policy)

  • Ensure that the food is safe and complies with all applicable legislative and regulatory requirements, such as:
    • Sections 4 (1) and 7 of the Food and Drugs Act (FDA)
    • Section 3.1(1) of the Fresh Fruit and Vegetable Regulations
    • Section 2.1 (1) of the Processed Products Regulations
    • Any applicable provincial regulations
    In order to demonstrate due diligence the Listeria Policy should be implemented.
  • Be aware of their RTE products physico-chemical parameters (aw, pH), stated shelf-lives and storage conditions
  • Communicate all positive results of Lm found in a RTE product or persistent Listeria spp. on food contact surfaces (FCS) to regulatory authorities (e.g., CFIA) as soon as possible
  • Implement a corrective action in response to unsatisfactory results
  • Have a mechanism in place to withdrawal/recall contaminated product, as applicable

RTE Food Industry - Processors

(Section 6.2.1 of the Listeria Policy)

  • Implement effective Good Manufacturing Practices (GMP) and/or Hazardous Analysis Critical Control Point (HACCP) system to minimize all potential sources of food contamination
  • Implement routine monitoring sampling (environmental and end-product)

RTE Food Industry - Importers

(Section 6.2.2 of the Listeria Policy)

  • Verify that the foreign processor is supplying safe product that complies with Canadian legislation
  • Provide information on the supplier's food safety programs, including process controls (e.g., Good Agricultural Practices (GAP), GMP, HACCP)
  • Implement safe food storage/handling procedures

RTE Food Industry - Exporters

(See section 6.2.3 of the Listeria Policy)

  • Comply with the requirements of the receiving country as well as Section 37 of the Food and Drugs Act:
    "…package and its contents do not contravene any known requirement of the law of the country to which it is or is about to be consigned has been issued in respect of the package and its contents in prescribed form and manner."

Government - Health Canada (HC)

(Section 3 of the Listeria Policy)

  • In consultation with CFIA and provincial/territorial governments, develops food safety standards and policies to minimize the risk of foodborne illnesses
  • Helps Canadians maintain and improve their health

Government - Canadian Food Inspection Agency (CFIA)

(Section 3 of the Listeria Policy)

  • Protects Canadians from preventable health risks through a fair and effective regulatory regime
  • Oversees the food industry to ensure that it meets its food safety responsibilities
  • Assesses industries validation data for product re-categorization

Government - Public Health Agency of Canada (PHAC)

(Section 3 of the Listeria Policy)

  • Promotes and protects the health of Canadians
  • Conducts surveillance of foodborne illness across Canada

Government - Provincial and Territorial Government (P/T Gov't)

(Section 3 of the Listeria Policy)

  • Oversees the food industry to ensure that it meets its food safety responsibilities
  • Assesses industries validation data for product re-categorization

Government - HC, CFIA, PHAC, P/T Gov't

(Section 3 of the Listeria Policy)

  • Work together to investigate the source of any Lm related illnesses when an outbreak is suspected
  • Engage the medical community, public health officials, the food industry and consumers on issues related to Lm and listeriosis

Consumers

(Section 3 of the Listeria Policy)

  • Learn and implement safe food handling practices
  • Informed food selection
  • Safe food handling, preparation and storage practices

Topic 4: Fresh and Processed Produce Subject to the Listeria Policy

Food Subject to the Listeria Policy

(Section 1 of the Listeria Policy)

  • Domestically produced RTE food are subject to the Listeria Policy
  • Imported RTE food are subject to the Listeria Policy
  • Retail food are not subject to the Listeria Policy
  • Food prepared and sold at foodservice establishments are not subject to the Listeria Policy

Food Subject to the Listeria Policy

(Appendix A of the Listeria Policy)

The Listeria Policy applies to RTE foods (as defined in the Appendix A of HC's Listeria Policy):

  • That do not require any further preparation before consumption, except washing/rinsing, thawing or warming; and
  • That have been subjected to some form of processing in order to render them RTE; and/or
  • Which have been subjected to another process to extend their shelf-life

Fresh Produce Subject to the Listeria Policy

  • RTE fresh-cut fruit and vegetables that have been either washed and peeled, either sliced, chopped or shredded prior to being packaged for sale and are intended to be consumed raw and not for further processing or cooking

Fresh Produce Not Subject to the Listeria Policy

  • Whole fresh fruit and vegetables that have only been trimmed, cleaned, brushed, washed, graded, packaged or otherwise prepared for human consumption
  • Non-RTE fresh-cut produce that have been either washed, peeled, sliced, chopped or shredded prior to being packaged for sale with cooking instructions on the package

RTE Processed Fruits and Vegetables Subject to the Listeria Policy

RTE fruits and vegetables subjected to a process that does not achieve a 5 log reduction and packaged in non-hermetically sealed containers.

  • Frozen fruits
  • Certain frozen vegetables
  • Refrigerated pickles, olives and sauerkraut

RTE Processed Fruits and Vegetables Not Subject to the Listeria Policy

RTE fruits and vegetables processed to a minimum of 5 log reduction using a validated thermal process, retorting, aseptic process and are packed in hermetically sealed containers.

  • Canned fruits
  • Canned vegetables
  • Jams and jellies
  • Shelf stable fruit juices
  • Shelf stable pickles
  • Shelf stable olives

Topic 5: RTE Food Categories

RTE Food Categories

In the Listeria Policy, RTE foods have been classified into two categories, based upon health risk.

  • Category 1
  • Category 2 contains two subgroups:
    • Category 2A
    • Category 2B

Regardless of the RTE food categorization, industry must produce safe foods as per the Food and Drugs Act and Regulations.

Category 1

(Section 6.1, 7.3, Table 1 and Appendix A of the Listeria Policy)

Definition: RTE fresh-cut produce, which can support the growth of Lm throughout the stated shelf-life to levels > 100 CFU/g and which have a refrigerated shelf-life of > 5 days.

By default, a food is considered Category 1 if validated data is unavailable, insufficient, or inadequate to demonstrate it is either a Category 2A or 2B or its categorization has not been confirmed by the regulatory authorities (e.g., CFIA).

Sample Size: 5 units of minimum 100 g each

Samples should be representative of the lot and the production conditions, taken aseptically at random from each lot.

Laboratory Method: Any enrichment (presence/absence) method for Lm published in HC's Compendium of Analytical Methods.

Action Level: Detection in 125 g (5 x 25 g analytical units analysed either separately or composited).

Nature of Concern: Health Risk 1

A situation where there is a reasonable probability that the consumption/exposure to a food will lead to adverse health consequences which are serious or life-threatening or that the probability of a foodborne outbreak situation is considered high.

Level of Priority: High; for industry control, monitoring, verification and regulatory oversight/compliance activities.

Category 2A

(Section 6.1, 7.3, Table 1 and Appendix A of the Listeria Policy)

Definition: RTE fresh-cut produce, in which a limited potential for growth of Lm to levels ≤ 100 CFU/g can occur throughout the stated shelf-life.

  • RTE food with a refrigerated shelf-life of ≤ 5 days; validation not required.
  • RTE foods which are known to occasionally contain low levels of Lm and do not have a kill step that achieves a ≥ 5 log reduction in numbers of Lm; validation required.
  • If information is insufficient, inadequate or no information exists to demonstrate that there is limited growth of Lm throughout the shelf-life, as determined by validated data, the food will be considered as a Category 1 RTE food.

Sample Size: 5 units of minimum 100 g each

Laboratory Method: Any enumeration method for Lm published in HC's Compendium of Analytical Methods.

Action Level: > 100 CFU/g in any one sub-unit (5 x 10 g analytical units).

Nature of Concern: Health Risk 2

The health risk identified represents a situation where there is a reasonable probability that the consumption/exposure to a food will lead to temporary or non-life threatening health consequences, or that the probability of serious adverse consequences is considered remote.

Level of Priority: Medium to low; for industry control, monitoring, verification and regulatory oversight/compliance activities.

Category 2B
(Section 6.1. 7.3, Table 1 and Appendix A of the Listeria Policy)

Definition: RTE food, in which Lm cannot grow (i.e., < 0.5 log CFU/g throughout the stated shelf-life).

RTE food that meets the following criteria will not support the growth of Lm:

  • Stored under "frozen" conditions (until consumption), or
  • pH < 4.4, regardless of aw, or
  • aw < 0.92, regardless of pH, or
  • Combination of pH < 5.0 and aw < 0.94

* Validation not required.

Note: Products not meeting these physico-chemical parameters require scientific validated data to demonstrate that the food does not support the growth of Lm. This validation information must be reviewed and confirmed by the relevant regulatory authority.

Sample Size: 5 units of minimum 100 g each

Laboratory Method: Any enumeration method for Lm published in HC's Compendium of Analytical Methods.  

Action Level: > 100 CFU/g in any one sub-unit (5 x 10 g analytical units).

Nature of Concern: Health Risk 2

A situation where there is a reasonable probability that the consumption/exposure to a food will lead to temporary or non-life threatening health consequences, or that the probability of serious adverse consequences is considered remote.

Level of Priority: Low; for industry control, monitoring, verification and regulatory oversight/compliance activities.

RTE Food Categories

(Section 6.1 of the Listeria Policy)

RTE Foods Intended for High-Risk Population

  • Should receive the highest priority for industry control, monitoring and verification, as well as regulatory oversight and compliance activities.
  • May be considered to represent a Health Risk 1 concern, irrespective of product type and associated category rating (1, 2A ou 2B).
RTE Food Categories Summary Table
Category 1 Category 2A Category 2B
Definition RTE fresh-cut produce, which can support the growth of Lm throughout the stated shelf-life to levels > 100 CFU/g and which have a refrigerated shelf-life of > 5 days RTE foods, in which a limited potential for growth of Lm to levels no greater than 100 CFU/g can occur throughout the stated shelf-life RTE foods, in which Lm cannot grow
Sample Size 5 units of minimum 100 g each 5 units of minimum 100 g each 5 units of minimum 100 g each
Laboratory Method Any enrichment (presence/absence) method for Lm published in HC's Compendium of Analytical Methods Any enumeration method for Lm published in HC's Compendium of Analytical Methods Any enumeration method for Lm published in HC's Compendium of Analytical Methods
Action Level Detection in 125 g > 100 CFU/g in any one sub-unit > 100 CFU/gin any one sub-unit
Nature of Concern Health Risk 1 Health Risk 2
(Health Risk 1 if food is intended for high risk groups or intended for use in Cat. 1 food)
Health Risk 2
(Health Risk 1 if food is intended for high risk groups or intended for use in Cat. 1 food)
Level of Priority High Medium - Low
(unless the food is intended for high risk groups or intended for use in a Cat. 1 food)
Low
(unless the food is intended for high risk groups or intended for use in a Cat. 1 food)

Topic 6: Methods of Analysis

Methods of Analysis

(Sections 7.2 and 7.3 of the Listeria Policy)

  • Environmental sampling should be conducted according to MFLP-41
  • Testing for environmental and product samples should be conducted according to any method published in HC's Compendium of Analytical Methods in which the "Application" section is appropriate for the intended purpose

To find the appropriate laboratory method, go to HC's The Compendium of Analytical Methods:

  • Select Volume 2 to find all methods that start with MFHPB
  • Select Volume 3 for all methods that start with MFLP

For example, after selecting Volume 3, MFLP-41, the method will open and the "Application" section will be found under section 1.

Excerpt from the application: "This environmental sampling procedure applies to both food contact surfaces and non-food contact surfaces in a food manufacturing plant. It describes the procedures to be used for the collection and handling of environmental samples for microbiological assessment."

To find an accredited lab go to:

Topic 7: Validation of RTE Foods for Re-categorization

For more information, refer to HC's document, Validation of Ready-to-Eat Foods for Changing the Classification of a Category 1 into a Category 2A or 2B Food.

Validation – Definition

(Section 2 of HC's Validation Document)

Codex Alimentarius Commission (2008) defines validation as:

"Obtaining evidence that a control measure or combination of control measures, if properly implemented, is capable of controlling the hazard to a specified outcome."

Validation of RTE Foods for Re-Categorization – Purpose

(Section 1 of HC's Validation Document)

  • Demonstrate using scientific evidence that a RTE food product, covered by HC's Listeria Policy, is Category 2 (2A or 2B)
  • The product is considered to be Category 1, if insufficient, inadequate or no information exists to demonstrate a 2A or 2B categorization or if the categorization has not been confirmed by regulatory authorities (e.g., CFIA)

Pre Validation

(Section 3.1 and 4.1 of HC's Validation Document)

a) Hazard identification:

  • Presence of unacceptable levels of Lm in RTE foods as per HC's Listeria Policy (i.e., > 100 CFU/g of Lm at any time throughout the stated shelf-life)

b) Identification of food safety outcome:

  • Category 2A RTE Food: Lm, when present, should be limited to a maximum of 100 CFU/g throughout the stated shelf-life
  • Category 2B RTE Food: Growth of Lm will be less than a 0.5 log CFU/g increase throughout the stated shelf-life of the RTE product

c) Identification of the measure(s) that need to be validated:

  • Challenge studies need to demonstrate when RTE foods are processed according to specified parameters, the desired food safety outcome is achieved

Validation of RTE Foods for Re-Categorization

(Section 2 of HC's Validation Document)

  • Challenge Studies – Mandatory
  • Identification of Key Process Parameters, and Provisions of Evidence of their Control – Mandatory
  • Literature Review – Recommended
  • Modelling – Optional

Validation of RTE Foods for Re-Categorization

(Section 3.2 and 4.2 (b) of HC's Validation Document)

Challenge Studies – Mandatory

  • To determine the ability of the product to support limited or inhibit the survival and growth of Lm throughout the duration of the stated shelf-life
  • Results must demonstrate that the food safety outcome is met

Challenge studies should be conducted as per HC's, Lm Challenge Testing of Ready-to-Eat Refrigerated Foods.

Validation of RTE Foods for Re-Categorization

(Section 3.2 and 4.2 (b) of HC's Validation Document)

Challenge Studies – Recommended Experimental Design

Lm strains

  • Use a pool of at least 3-5 strains (can be up to 10)
  • Certain serotypes should be included (1/2a, 1/2b and 4b)
  • Include strains isolated from the same, or similar types of food
  • If available, use an outbreak strain, or sporadic cases
  • Cultures are available from international culture collections (e.g., ATCC and ILSI)

Preparation and enumeration of cells

  • Consult with an expert food microbiologist
  • Storage of cells should minimize the number of transfers to minimize mutations
  • HC's Challenge Study document provides guidance to:
    • Avoid multiple passages
    • Incubate cells at refrigeration temperatures since the RTE foods will be refrigerated
    • Enumerate cells of a working inoculum

Inoculum level

  • Inoculation level used should be10-30 CFU/g to attempt Category 2A classification
  • Inoculation level to demonstrate Category 2B classification has not been pre-set by regulatory authorities. The initial level of inoculum can vary, so long as, for example, it does not overload the preservative system/natural hurdles associated with the product and that the concentrations can be easily enumerated. Examples of level of inoculation are presented in Table 1 of HC's, Lm Challenge Testing of RTE Foods.

Sampling design

  • Minimum of 3 lots of products must be tested for Lm in triplicate at each sampling time (i.e., a minimum of 5* time points throughout the stated shelf-life, including time zero and at the end of the shelf-life).

    *If the product has an extended refrigerated shelf-life, additional time points throughout the stated shelf-life of the product should be considered, in order to account for possible variations in the growth of Lm.

Preparation of food product

  • Need to know the critical parameter and process variability of the product
  • Use "worse-case" conditions (i.e., most permissive for growth of Lm)
  • Consider competing background microorganisms

Inoculation of food product

  • Inoculation method should reflect the way contamination is likely to occur and the condition of the product at that point
  • Examples of inoculation methods are available in HC's, Lm Challenge Testing of RTE Foods

Special product packaging conditions

  • Inoculated product should be packaged as intended for sale
  • Special care is needed to maintain Modified Atmosphere Packaging (MAP) conditions following inoculation (e.g., must be monitored during challenge study)

Incubation of inoculated food products

  • Validation studies for changing the classification of a Category 1 into a Category 2A or 2B food must be performed at a temperature of 7 °C or above

Enumeration and enrichment methods

  • Samples should be diluted 1:5 (can use up to 1:10 for difficult to spread matrices)
  • Should use quantitative determination for Lm (e.g., MFLP-74 available in HC's Compendium)

Documentation of results

  • Document all results of the challenge study in a report
  • Include information on all required components of the challenge study
  • Raw data and any graphical representations/interpretations should be included

The experimental design must be detailed and rationale for each parameter should be included in the validation data.

Validation of RTE Foods for Re-Categorization

(Section 3.2 and 4.2 (c) of HC's Validation Document)

Identification of Key Process Parameters, and Provision of Evidence of their Control – Mandatory

  • Key process parameters (e.g., aw, pH) need to be clearly identified and documented
  • Adequate controls of key process parameters must be implemented and documented to provide evidence that the food safety outcome is not compromised
  • The same controls must be applied to the process parameters used in the challenge study

Validation of RTE Foods for Re-Categorization

(Section 3.2 and 4.2 (a)(d) of HC's Validation Document)

Literature Review – Recommended

  • Pertinent publications should include possible level of Lm contamination and growth profile in the RTE product(s) and/or similar products

Modeling – Optional

  • Mathematical modeling could be conducted for a group of similar RTE products
  • A challenge study must be performed on the RTE product which represents the highest risk for Lm within the grouping
  • A rationale supported by scientific evidence and the modeling documentation should be provided for evaluation

Validation – Additional Information

(Section 5 of HC's Validation Document)

  • After validation, if a change is made to a control measure or product, the appropriateness of the validation studies supporting the categorization of the RTE food may need to be confirmed.
  • If the change is determined by regulatory authority to be substantial, the need for re-validation/re-categorization may be triggered.

Other approaches to validation may be considered by the regulatory authority, on a case by case basis.

Validation – Summary

(Section 1 and 5 of HC's Validation Document)

  • It is the responsibility of the processor/importer to demonstrate in which category their RTE food belongs.
  • When industry wants to re-categorize a RTE product, validation studies should be completed according to HC's procedures.
  • Validation data should be submitted to the relevant regulatory authority (i.e., CFIA) for evaluation and confirmation.

Topic 8: Industry Monitoring

Industry Monitoring

(Section 7 and Figures 1, 2 and 3 of the Listeria Policy)

  • Monitoring sampling is conducted to verify the effectiveness of the control measures which are used to eliminate, inhibit and prevent the growth of Lm
  • Sampling should include both: Environmental and End-Product

Industry Monitoring – Routine Environmental Sampling

(Section 7.2 of the Listeria Policy)

  • Test for the presence of Listeria spp. on both food contact surface (FCS) and non-food contact surface (Non-FCS).
  • The number of meaningful sample sites (preferably 10) depends upon the complexity of the processing system.
  • Environmental sampling for Listeria spp. helps verify the effectiveness of the GMPs/HACCP.
  • Presence of Listeria spp. on FCS could indicate that the controls (i.e., sanitation) are inadequate.
  • If Non-FCS samples (near to FCSs) are found positive for Listeria spp. on a regular basis, FCS should be tested more frequently.

Persistent contamination could be an indication of inadequate GMPs.

Industry Monitoring – End Product Testing

(Section 6.2, 7.3 and Table 1 of the Listeria Policy)

  • End-product sampling may be conducted for various reasons, including when FCS test positive for Listeria spp.
  • Testing may be required to verify RTE foods meet compliance criteria for Lm.
  • Samples submitted for Lm analysis should consist of 5 sample units of at least 100 g each.

Listeria Policy: Figures 1, 2 and 3

(Section 7.2 of the Listeria Policy)

Figure 1: Sampling Guidelines for FCS and Category 1 RTE food

Figure 2: Sampling Guidelines for FCS and Category 2 RTE food

Figure 3: Sampling Guidelines for Non-FCS

Figure 1: Sampling Guidelines for FCSs (Category 1 RTE Food)

Figure 1: Step A

Purpose is to determine if Listeria spp. is present

  • Collect FCS samples, as per MFLP-41
    • Collect preferably 10 FCS samples
    • Samples should be collected during production, typically 3 hours into production
    • Frequency and the number of sampling sites should reflect the manufacturing processes and controls
    • Special circumstances may warrant an increase in the frequency of sampling and/or the number of sample sites
  • Analyze samples either individually, or as composites
  • Use any enrichment (presence/absence) method for Listeria spp. published in HC's Compendium of Analytical Methods in which the "Application" section is appropriate for the intended purpose
  • FCS positive for Listeria spp.?
    • No, continue routine monitoring program.
    • Yes, proceed to Step B.

Figure 1: Step B

(Section 6 and 7 of the Listeria Policy)

  • Initiate corrective actions ASAP
    • Step B and onward should be recorded to include information on corrective actions, investigational sampling, product testing and/or disposition
    • Corrective actions:
      • Prevent or eliminate Lm
      • Control conditions that will enable growth
      • Be monitored to confirm effectiveness
Corrective actions should include
  • In-depth review of the food safety system (GMPs/HACCP) to ensure compliance and adjusting it, if necessary
  • Improvement in sanitation procedures
  • Identification of the source of the contamination through investigational sampling
  • After corrective actions are implemented:
    • All products from that line should be placed on hold
    • Collect FCS samples to verify efficacy of corrective actions, as per MFLP-41
      • At a minimum, the FCS sites in the routine monitoring program should be included
      • The number and location of samples sites should be adequate to verify that the entire line is negative for Listeria spp.
    • Analyze FCS samples individually
    • Use any enrichment (presence/absence) method for Listeria spp. published in HC's Compendium of Analytical Methods in which the "Application" section is appropriate for the intended purpose
  • (2nd) FCS positive for Listeria spp.?
    • No, resume routine monitoring program and release product put on hold at Step B.
    • Yes, test product as per Table 1, Listeria Policy and proceed to Step C.
Test product as per Table 1, Listeria Policy
  • End-product sampling should be linked to the environmental sampling
  • 5 sample units should be collected aseptically at random from the implicated lot
  • Each sample unit should consist of at least 100 g

Lm detected in 125 g – consult with regulatory authorities (e.g., CFIA) about disposition of product.

Lm not detected in 125 g – consult with regulatory authorities (e.g., CFIA). A health risk assessment (HRA) may be requested.

Figure 1: Step C

  • Notify regulatory authorities (e.g., CFIA) as soon as possible
  • Repeat Step B until FCS samples are negative for Listeria spp. and product samples are negative for Lm
    • Hold and test each lot of product until the results demonstrate that control of Listeria has been achieved
  • Sample FCS and end-product until results are negative for 3 or more consecutive production days and product samples do not exceed criteria for Lm

Figure 2: Sampling Guidelines for FCSs (Category 2 RTE Food)

  • Figure 1 and Figure 2 are very similar.

Figure 2: Step A

  • Step A is the same in both flowcharts; 10 samples from food contact surfaces would be collected and analyzed for the presence of Listeria spp.

Figure 2: Step B

  • However, in Step B, the two diagrams begin to look a bit different. Figure 1 recommends holding product produced on the implicated line following the first positive FCS sample, whereas Figure 2 recommends holding product produced on the implicated line after the second positive FCS sample. The Listeria Policy recommends that subsequent lots be put on hold after at Step C.

Figure 2: Step C

  • In Figure 1, end-product testing is recommended if a second FCS sample is positive, where as in Figure 2 end-product testing is recommend if a third FCS sample is positive. 
  • There is also a difference regarding the analysis and the action level for Lm between the two figures. For a Category 1 food, a regulatory authority should be contacted regarding product disposal if Lm is detected in 125 g. For a Category 2 food, these actions should occur if Lm exceeds 100 CFU/g at any point throughout the product's stated shelf-life. If the presence of Lm does not exceed these criteria, the facility should still be in contact with a regulatory authority, and a health risk assessment (HRA) may be requested.

Figure 2: Step D

  • Finally, Figure 2 has an extra step, Step D.
  • Determine if positives are due to processing conditions (possible HRA) or due to recontamination, continue intensified corrective actions until FCS are negative and review all results with regulatory authorities (e.g., CFIA).
  • For category 2 products, the company can resume routine monitoring sampling activities once FCS sample is negative for Listeria species and their respective product sample are negative for Lm or within the acceptable limits (Lmless then or equal to 100 CFU/g). The Listeria Policy states that product samples found with acceptable level of Lm not exceeding 100 CFU/g still may require an HRA, depending on different criteria (product intended for high risk population, or used in Category 1 product, remaining shelf-life of the sample, etc.). 
  • All positive results from Lm in a RTE food or persistent Listeria spp. on a FCS should be communicated ASAP to the regulatory authority (e.g., CFIA).

Figure 3: Sampling Guidelines for Non-FCSs, in Proximity to FCS (Category 1 and 2 RTE Food)

Figure 3: Step A

  • Collect non-food contact surfaces, as per MFLP-41 (either individually or as composites).
  • Non-FCS positive for Listeria species?
    • No, continue routine monitoring program.
    • Yes, proceed to Step B…

Figure 3: Step B

  • Initiate corrective actions as soon as possible.
  • Re-sample Non-FCS and analyze individually identify source of contamination and/or to verify efficacy of corrective actions.
  • Non-FCS positive for Listeria species?
    • No, resume routine monitoring program.
    • Yes, proceed to Step C…

Figure 3: Step C

  • Repeat Step B until Non-FCS samples are negative for Listeria species.
  • If Non-FCS samples are found positive for Listeria species on a regular basis, nearby FCS should be tested more frequently.

Industry Monitoring

(Section 7.4 of the Listeria Policy)

  • Trend analysis should be part of a company's verification process
  • Data can be used to model and predict risk
  • The results should be used to achieve improved control of Listeria over time

Topic 9: CFIA Oversight and Verification

CFIA Oversight

  • Verification of industry's compliance with applicable Acts and Regulations
  • Assessment of GMPs at RTE fresh-cut and processed fruit and vegetable establishments
  • Product testing of domestic and imported RTE fresh-cut and processed fruit and vegetables for the detection of Lm

CFIA Verification

(Section 6.2.1 and 6.2.2 of the Listeria Policy)

  • Conduct on-site inspections in order to verify Listeria controls and corrective actions
  • Assess Listeria controls of foreign suppliers at the importer
  • Collect end-product and/or environmental samples
  • Detain and/or recall of affected product, as applicable

CFIA Verification

(Section 6.2.1.1 of the Listeria Policy)

Focus of CFIA's On-Site Inspection

  • Production procedures (e.g., GMPs/HACCP Program)
  • Process controls
  • Deviation and corrective action procedures
  • Equipment design, ventilation and packaging material
  • Sanitation practices
  • Employee hygiene practices
  • Process flow (product/personnel)
  • Post-process handling, storage and distribution
  • Product traceability

Questions and Answers

Additional Questions? Send an email to FFV.CFIA@inspection.gc.ca

Summary of Questions and Answers

Note: the "Policy on Listeria monocytogenes in Ready-to-Eat Foods" is referred to as the "Listeria policy" in this document.

Questions and answers have been reviewed by the Canadian Food Inspection Agency Food Safety Science Directorate, Fresh Fruit and Vegetable Program and Processed Products Program, in consultation with Health Canada (2013).

Fresh and Processed Produce Subject to the Listeria Policy

Why are ready-to-eat retail prepared foods exempt from the Listeria policy?

The scope of the Listeria policy is to provide guidance to ready-to-eat (RTE) food processors on how to address Listeria in the environment of processing establishments and therefore does not address the foodservice or retail establishments. Foods prepared at retail are under provincial/territorial jurisdiction. One of the roles of provincial/territorial governments is to oversee the retail sector to ensure that it meets its food safety responsibilities. If RTE retail prepared foods are tested and an organism of concern is detected, a Health Risk Assessment (to be conducted by the Bureau of Microbial Hazards (BMH), Food Directorate, Health Products and Food Branch (HPFB), Health Canada) may be requested.

Why are frozen fruits (e.g., frozen berries) included in the Listeria policy while whole fresh fruits (e.g., fresh berries) are excluded?

The basis for frozen fruits being included is that, unlike fresh fruits, they undergo processing during which potential Listeria contamination can occur.

The Listeria policy states that the health risk changes if the product is used by a high risk population; please explain.

High risk populations include pregnant women, elderly and/or immunocompromised individuals (e.g., AIDS patients, transplant recipients, cancer patients, etc.).

RTE foods that are produced for consumption by individuals, who are known to be in the high-risk population, may be considered to represent a Health Risk 1 concern, if contaminated by Listeria monocytogenes, irrespective of the Listeria policy product Category. As per Table 1 of the Listeria policy, the presence of Listeria monocytogenes in a Category 1 RTE food would trigger a Health Risk 1 concern and counts of Listeria monocytogenes > 100 CFU/g in a Category 2 RTE food would trigger a Health Risk 2 concern. However, for Category 2 RTE foods intended for a high risk population, if counts are > 100 CFU/g, the product(s) would automatically be considered a Health Risk 1 situation. If counts ≤ 100 CFU/g are detected in such products (i.e., Category 2 RTE food produced for a high risk population), a Health Risk Assessment (to be conducted by the Bureau of Microbial Hazards (BMH), Food Directorate, Health Products and Food Branch (HPFB), Health Canada) may be requested which may also lead to a Health Risk 1 concern.

Would providing specific cooking instructions on the consumer package of fresh-cut fruit and vegetables products (e.g., fresh-cut mushrooms, vegetable kebobs for BBQ) be sufficient to exclude these products from the Listeria policy?

Product labelling cannot be used as the sole criterion to determine inclusion or exclusion from the Listeria policy. For example, fresh-cut mushrooms bearing cooking instructions would still be included in the scope of the Listeria policy. The Listeria policy contains the criteria for determining whether a product is included in the policy, irrespective of the labelling claim found on a product.

Scenario - What Category would frozen meals (containing vegetable components) fall into?

RTE frozen meals containing vegetables would fall under Category 2B as these foods do not support the growth of Listeria monocytogenes since they are frozen until consumption. However, if a frozen Category 2B product were to be temperature-abused causing it to thaw, or was sold refrigerated instead of frozen, growth of Listeria monocytogenes could potentially occur. A finding of Listeria monocytogenes in these products would lead to follow-up action(s) and a Health Risk Assessment. In these situations, Category 2 foods may be assessed to represent a Health Risk 1 concern.

Scenario - What Category would pre-cooked refrigerated or frozen mixed vegetable soup fall into?

Pre-cooked frozen mixed vegetable soups would fall under Category 2B since these foods do not support the growth of Listeria monocytogenes because they are frozen until their preparation for consumption. However, these products could be assessed to represent a Health Risk 1 situation (under the circumstances described in Question 6a).

Pre-cooked refrigerated mixed vegetable soups would fall under Category 1, unless the physico-chemical parameters of the products are such that the growth of Listeria monocytogenes will not occur (i.e., pH < 4.4 regardless of aw, aw < 0.92 regardless of pH, combinations of factors pH < 5.0 and aw < 0.94), in which case they would fall under Category 2B. For these products, food processors would need to monitor and maintain records of physico-chemical parameters such as pH and aw, demonstrating that they continue to meet the criteria that justify their classification in this category. If information is insufficient, inadequate or no information exists to demonstrate that there is no potential growth of Listeria monocytogenes throughout the shelf-life, the food will be treated by default as a RTE food in which growth of Listeria monocytogenes can occur i.e., Category 1 RTE food.

Would the following (washed or unwashed) products be included in the Listeria policy: sprouted seeds/bean sprouts, micro greens, leafy greens and whole mushrooms?

Any types of sprouts, micro greens, leafy greens or whole mushrooms are considered as whole raw fresh fruit and vegetables, i.e., whole fresh fruit and vegetables that have only been trimmed, cleaned, brushed, washed, graded, packaged or similarly handled. According to the Listeria policy, whole fresh fruit and vegetables are not subject to the provision of this policy.

If a product is labelled as non RTE, does this exempt it from the Listeria policy?

Product labelling cannot be used as the sole criterion to determine inclusion or exclusion from the Listeria policy. The Listeria policy contains the criteria for determining whether a product is included in the policy, irrespective of the labelling claim found on a product.

Ready-to-Eat Food Categories

Scenario - If a company has a regular monitoring program for Listeria monocytogenes end-product sampling and can demonstrate that there is no Listeria monocytogenes, can this information impact the category of the products (e.g., lower the Category from 1 to 2A)?

The categorisation of a RTE food is based on the growth potential of Listeria monocytogenes in the product: Good Manufacturing Practices (GMPs) or Hazard Analysis Critical Control Point (HACCP) are means to have effective control measures in place to limit or eliminate the incidence of Listeria contamination in a facility and in a food product. Industry interested to proceed with the re-categorisation of a RTE food will have to provide scientific evidence (validated data), to be reviewed and confirmed by regulatory authorities. They should follow Health Canada's guidance document "Validation of Ready-to-Eat Foods for Changing the Classification of a Category 1 into a Category 2A or 2B Food – in relation to Health Canada's Policy on Listeria monocytogenes in Ready-to-Eat Foods (2011)."

Would other types of treatments be considered a 'kill step' other than thermal treatment (e.g., sanitation, washing of fresh produce)?

A kill step refers to any validated treatment that achieves a minimum of 5 log reduction in number of Listeria monocytogenes. Thermal treatment is an example of a kill step that could achieve this log reduction, based on specific time and temperature. Washing treatments applied on fresh fruit and vegetables are not considered to be a kill step, unless it is proven it achieves a 5 log reduction during the treatment.

Physico-chemical parameters (pH and aw)

How many pH readings should be taken per lot per year, to ensure the product consistently meets < 4.4 and is therefore considered a Category 2B?

Physico-chemical parameters that would not permit the growth of Listeria monocytogenes are defined in the Listeria policy as being in the following range: pH < 4.4 regardless of aw, aw < 0.92 regardless of pH, combinations of factors pH < 5.0 and aw < 0.94. Hence, a ready-to-eat (RTE) food consistently having values within the ranges specified above would be considered as a Category 2B food.

The Listeria policy does not prescribe a specific frequency. The frequency depends on different parameters such as the nature of the product, production process and volume produced. For instance, if the pH is close to the 4.4 limit and/or requires addition of acidulants to achieve a pH below 4.4, frequent checks are likely necessary and potentially every lot, if pH has been defined as a Critical Control Point (CCP). Where pH is achieved through processing, ruggedness studies on the processing methods should be performed to determine which variables may have an impact on the pH of the final product. Therefore if a variable is deemed to have a high impact on the pH of the final product there should be measures in place to ensure this parameter is controlled. However, if the pH of the food is naturally low i.e., its pH is significantly lower than 4.4 and there is no need to control the pH through processing (e.g., a naturally acidic fruit),) then the frequency of pH checks can be lowered/reduced. It is the responsibility of the operator to develop a process, a monitoring and/or verification sampling plan that ensures all applicable product lots have a pH < 4.4.

How should the pH be taken for a fruit salad (e.g., a pH reading for each different type of fruit once they are mixed together, each different type of fruit prior to mixing, and/or the mixture of all fruits together)?

The pH for each of the different fruit components in the salad should be assessed and the overall categorisation of the fruit salad product would be based on the highest pH fruit in the final product. However if a slurry of all mixed fruits was done and this pH measurement was shown to be equal to or above 4.4, it can be immediately determined that the fruit salad is not a Category 2B food (unless validation studies are provided by the company to support that the growth of Listeria monocytogenes cannot occur and those validation studies are confirmed by regulatory authorities). If pH measurement for the mixed fruit slurry was less than 4.4 (pH < 4.4), categorisation of the product cannot be made and would be considered incomplete. Additional pH measurements would be required to confirm that each separate fresh-cut fruit component has a pH < 4.4. In fact, for a Category 2B determination (without validation studies), the critical pH parameters (i.e., pH < 4.4), must be shown to be achieved throughout the entire fruit salad. Health Canada recommends the use of the method MFHPB-03 for the determination of pH of foods available from Health Canada's Compendium of analytical methods (Volume 2).

If the product consistently shows a pH of < 4.4, does industry need to provide evidence (e.g., data, records) of the pH values?

Operators should record all pH measurements they perform on their products to provide evidence that the pH criterion for Category 2B products is met. In the absence of evidence, the product may be treated as a Category 1 food by default.

Methods of Analysis

Where can Listeria monocytogenes strains be obtained?

Strains can be purchased from a commercial culture supplier or organisation.

Is there a Listeria monocytogenes indicator organism?

Listeria spp. are considered indicator organisms for Listeria monocytogenes for food contact surfaces and non-food contact surfaces in a food industry environment. The presence of abnormally high levels of other groups of environmental organisms (e.g., Aerobic Colony Count (ACC), coliforms) on surfaces post-sanitation may also be an indication of sanitation issues, and potential presence of Listeria monocytogenes.

Is MFHPB-29 approved by Health Canada and/or the Canadian Food Inspection Agency to address environmental sampling?

This method is applicable to the rapid detection of Listeria spp. and may be used for environmental samples.

Note however that the confirmation section of MFHPB-29 states the following:

Note: If the results indicate that Listeria spp. have not been detected, it is understood that the presence of Listeria monocytogenes has also not been detected, since no species belonging to the Listeria genus were detected. However, if Listeria spp. are detected, regardless of the amount of colony screening or additional confirmation steps done, these results cannot be used to state that Listeria monocytogenes is absent. Report all species of Listeria that are identified.

When analyzing laboratory results, what is the difference between presence/absence vs. 100 CFU/g?

Presence/absence methods are more sensitive than enumeration methods. Presence/absence is a qualitative result, by which as little as 1 to 5 CFU of Listeria monocytogenes can be detected in the entire sample (for instance, as little as 1 to 5 CFU in the entire 125g sample size), and the test result will be reported as being positive for the presence of Listeria monocytogenes.

The enumeration method reports the actual counts of Listeria monocytogenes per gram of food sample (for instance a level of 100 CFU/g), which is a quantitative result. The enumeration method MFLP-74 can detect Listeria monocytogenes if present at levels equal to or greater than 5 CFU per gram of sample (based on a product/diluent ratio of 1 in 5).

Since the detection limit in a qualitative test is much lower than for a quantitative test, it is possible that a product would test positive in presence/absence of Listeria monocytogenes but would not be detected by the enumeration test.

Can industry use non-accredited laboratories to test for Listeria spp. on food contact and non-food contact surfaces or Listeria monocytogenes in RTE foods?

It is not mandatory to use accredited laboratories but industry is encouraged to select testing labs that have received formal recognition for the required testing from a recognized accreditation body such as the Standard Council of Canada (SCC) or the Canadian Association of Laboratory Accreditation (CALA). According to the Listeria policy, analysis of "food contact surfaces/non-food contact surfaces/end products" for the presence of Listeria spp. or Listeria monocytogenes should be conducted using any method published in Health Canada's Compendium of Analytical Methods for Listeria spp. or Listeria monocytogenes in which the "Application" section is appropriate for the intended purpose (e.g., MFHPB methods and MFLP methods). To find an accredited laboratory and view their scope of accreditation, go to: SCC or to CALA webpages.

Is the log reduction referred to in the Listeria policy meant for Listeria alone or for total plate count?

The log reduction mentioned all through the Listeria policy is always specific to Listeria monocytogenes.

Validation of Ready-to-Eat Foods for Re-Categorisation

When a validation study is conducted, can the same data be used for a similar product? For example, if a validation study was conducted on fresh-cut romaine lettuce, can this data be used for another type of fresh-cut lettuce or if the fresh-cut romaine lettuce is a component of a mixture?

It is understood that it might not be practical to conduct laboratory challenge studies for each product being manufactured by one processor; it could potentially be acceptable to group comparable products. The highest risk product for Listeria monocytogenes growth, within the group, should be used to perform the laboratory challenge study. A rationale, supported by scientific evidence needs to be provided to justify the grouping of products as well as for the selection of the highest risk product. For more information, refer to question 9 of the Summary of Comments Received on Health Canada's Proposed Document Validation of Ready-to-Eat Foods for Changing the Classification of a Category 1 into a Category 2A or 2B Food – in relation to Health Canada's Policy on Listeria monocytogenes in Ready-to-Eat Foods (2011).

Under what conditions would a product need to be re-validated. Does the validation data for changing a product's categorisation from a Category 1 to a 2A or 2B remain valid indefinitely?

If a change is intended or is made to a control measure or in a product or process-related factor that is likely to affect the effectiveness of the control measure (for example, process control, process parameters, etc.), the appropriateness of the validation studies supporting the categorisation of the product under consideration may need to be confirmed. If the change is determined by the relevant regulatory authority to be substantial, the need for re-validation/re-categorisation may be triggered. If no changes are made, and if on-going monitoring and verification procedures demonstrate that the food safety outcome is maintained, then the classification remains valid.

Industry Monitoring

What is the recommended frequency and minimum number of swabs for routine environmental swabbing?

According to the Listeria policy, under section 7.2 and footnotes a & b of Figures 1, 2 & 3, the number of meaningful sites will vary according to the complexity of the processing system of a plant:

The frequency and points of sampling for routine sampling should be plant and/or line specific, based on the manufacturing processes and the controls that are present (Tompkin et al., 1992). An increase in sample sites (FCSs and non-FCSs) and frequency should be considered during and/or after special circumstances (e.g., construction, the installation of used or modified equipment, overhead/ceiling leaks in exposed product areas), which may provide an opportunity for control of L. monocytogenes to be lost.

Environmental sample collection should be conducted according to method MFLP-41, published in Health Canada's Compendium of analytical methods (Volume 3).

Please refer to section 7.2 in the Listeria policy for further guidance on environmental swabbing.

Should industry test for Listeria monocytogenes or Listeria spp. on end-product samples?

Industry should test for Listeria monocytogenes in finished product samples because finished product compliance criteria, as indicated in Table 1 of the Listeria policy, is based on Listeria monocytogenes.

Should industry test products for Listeria monocytogenes that do not fall under the Listeria policy?

In general, it is not recommended that companies test for Listeria monocytogenes in products that do not fall under the policy. However, some products outside the policy may pose a risk if contaminated with Listeria monocytogenes, and therefore companies may choose to test these products for Listeria monocytogenes, as applicable. In general, it is recommended that food companies adhere to Good Manufacturing Practices (GMPs) or have a Hazard Analysis Critical Control Point (HACCP) system in place to prevent contamination in their facility and in their food products.

If products that do not fall under the policy are tested by industry and Listeria monocytogenes is found, what is industry's responsibility?

In such situations, the industry must inform the regulatory authority immediately. A risk assessment will then be conducted to determine appropriate product action.

What does the term 'persistent contamination' mean?

According to the Listeria policy, under section 7.2:

If two or more samples from the same production line (i.e., using the same equipment) are found positive within a short timeframe, this is considered to be evidence of persistent contamination and an indication that the Listeria control program could be inadequate.

CFIA Oversight and Verification

During CFIA oversight, are storage/warehousing of imported products part of CFIA verification inspections?

All aspects of importer's Good Hygiene Practices (GHP)/GMP or HACCP system could be assessed to verify effective control over potential Listeria contamination, including safe food storage or general warehousing practices at the importer's facility. Moreover, importers should always have in their possession imported product information such as supplier, processor or exporter.

Does CFIA have the authority to implement the Listeria policy in non-federally registered facilities?

Under the Listeria policy, CFIA's role and responsibilities are to oversee the food industry and the effectiveness of its Listeria control program, to ensure that food manufacturers and importers of RTE products meet their food safety responsibilities and comply with all applicable legislative and regulatory requirements, whether they are federally registered or not. Oversight may include taking environmental and/or product samples, reviewing industry's sampling and/or corrective action plans, verifying that corrective actions have been implemented, taking enforcement action, etc.

Reference Documents

Health Canada

  1. Policy on Listeria monocytogenes in Ready-To-Eat Foods. (2011)
  2. Summary of Comments Received on Health Canada's Proposed Policy on Listeria monocytogenes in Ready-to-Eat - March to May, 2010
  3. The Compendium of Analytical Methods, Volume 2 and 3.
  4. Summary of Methods in the Compendium of Analytical Methods for Listeria spp. and Listeria monocytogenes. March 2012
  5. Validation of Ready-to-eat Foods for Changing the Classification of Category 1 into a Category 2A or 2B Food. – in relation to HC's Policy on Listeria monocytogenes in Ready-to-Eat Foods (2011)
  6. Summary of Comments Received on Health Canada's Proposed Document Validation of Ready-to-Eat Foods for Changing Classification of a Category 1 into a Category 2A or 2B Food – in relation to Health Canada's Policy on Listeria monocytogenes in Ready-to-Eat Foods - October to November, 2011
  7. Listeria monocytogenes Challenge Testing of Ready-to-Eat Refrigerated Food.

Canadian Food Inspection Agency

  1. General Principles of Food Hygiene, Composition and Labelling
  2. Good Importing Practices for Food, Code of Practice
  3. Code of Practice for Minimally Processed Ready-to-Eat Vegetables
  4. Food Safety Enhancement Program Manual
  5. Guidelines for the Use of Food Additives and/or Processing Aids Intended for Fresh Fruit and Vegetable
  6. Canada's 10 Least Wanted Foodborne Pathogens - Listeria monocytogenes

Codex

  1. Codex Alimentarius Commission, CAC/GL 69-2008. Guidelines for the Validation of Food Safety Control Measures - PDF (170 kb)
  2. Codex Alimentarius Commission, CAC/GL 61-2007. Guidelines on the Application of General Principles of Food Hygiene to the Control of Listeria monocytogenes in Foods - PDF (198 kb)
  3. Codex Alimentarius Commision, CAC – 2009a. Proposed Draft Microbiological Criteria for Listeria monocytogenes in Ready-to-Eat Foods - PDF (833 kb)
  4. Codex Alimentarius Commision, CAC – 2009b. Recommended International Code of Practice General Principles of Food Hygiene
  5. Codex Alimentarius Commission, CAC/RCP 53-2003. Code of Hygienic Practice for Fresh Fruits and Vegetables - PDF (250 kb)
  6. Codex Alimentarius Commission, CAC/RCP 46-1999. Code of Hygienic Practice for Refrigerated Packaged Foods with Extended Shelf Life - PDF (71.3 kb)
  7. Codex Alimentarius Commission, CAC/RCP 8-1976. Code of Practice for the Processing and Handling of Quick Frozen Foods - PDF (100 kb)

Other

  1. Ministry of Agriculture, Food and Rural Affairs. Food of Plant Origin Cleaning and Sanitation Guidebook. (2006)
  2. On-Farm Food Safety Manual from Canada - GAP/CHC. Chlorination of Water for Fluming and Cleaning Fresh Fruits and Vegetables and Cleaning Equipment. - PDF (2,1 mb) (2013)
  3. Standards Council of Canada – Directory of Accredited Clients
  4. Canadian Association for Laboratory Accreditation Inc.Directory of Accredited Laboratories
  5. Food and Drug Administration. Analysis and Evaluation of Preventive Control Measures for the Control and Reduction/Elimination of Microbial Hazards on Fresh and Fresh-Cut Produce. (2001)