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Archived - Code of Practice for the Hygienic Production of Sprouted Seeds

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This page was archived due to the coming into force of the Safe Food for Canadians Regulations. Archived information is provided for reference, research or record-keeping purposes only. It is not subject to the Government of Canada Web Standards and has not been altered or updated since it was archived. For current information visit Food.

February 2007

Table of contents

Amendment Records

Amendment Records

The following Code of Practice for the Hygienic Production of Sprouted Seeds replaces the Draft Code of Practice for the Hygienic Production of Sprouted Seeds, which was issued on September 11, 2001.

Introduction

In recent years, sprouted seeds have enjoyed increasing popularity in Canada. These crunchy newborn plants are favoured for their nutritional value, however, raw sprouts have been linked to outbreaks of food borne illness. In 1996, radish sprouts were associated with the world's largest E. coli O157:H7 outbreak, affecting over 6,000 people in Japan. In the United States, between 1995 and 1999, more than 10 outbreaks of food borne diseases have occurred due to contaminated sprouts.

The first Canadian outbreak associated with sprouts occurred in 1995. This outbreak was linked to the consumption of alfalfa sprouts contaminated with Salmonella Stanley. In this episode, 30 cases were reported in the province of British Columbia.During January of 1996, cases of Salmonella Newport food poisoning were reported in the provinces of British Columbia (58 cases) and Quebec (60 cases) due to contaminated alfalfa sprouts. During the fall of 1997, 124 cases of Salmonella Meleagridis infections across Canada and, during August and September 1999, 51 cases of Salmonella Java infections in Western Canada were linked to the consumption of alfalfa sprouts. Between April and June 2000, at least 12 cases of Salmonella Enteritidis PT 11B in Alberta and Saskatchewan, were associated with the consumption of mung bean sprouts produced from 2 different sprout manufacturers who used seeds from the same supplier. In February and March 2001, 84 cases of Salmonella Enteritidis PT 913 in Saskatchewan, Alberta and British Columbia were linked to consumption of mung bean sprouts. In the fall and winter of 2005, an outbreak of Salmonella Enteritidis PT 13, in Ontario was linked to the consumption of raw and lightly-cooked mung bean sprouts.

The microbial pathogens associated with sprouted seeds include Salmonella spp. and E. coli O157:H7. Outbreak investigations have indicated that microorganisms found on sprouts most likely originate from the seeds. Most seeds supplied to sprout manufacturers are produced primarily for field planting where the good agricultural practices (GAP) necessary to prevent microbial contamination of seeds intended for sprouting are not followed. As a result, the seeds may be contaminated in the field or during harvesting, storage or transportation. The germination process in sprout production involves keeping seeds warm and moist for four to seven days. In these conditions, low levels of microbial contaminants present on seeds can quickly reach levels high enough to cause illness.

Sprouted seeds must comply with the Food and Drugs Act and Regulations. Health Canada establishes microbial standards and guidelines to address potential risks. Those are published in the Health Canada's Interpretive Summary of Health Protection Branch Standards and Guidelines for Microbial Safety of Food. It is the industry's responsibility to put the necessary controls in place to produce safe sprouts. Through its inspection and product sampling activities, the Canadian Food Inspection Agency (CFIA) enforces the Food and Drugs Act with respect to Health Canada's guidelines.

This present Code recommends control of pathogens to occur in two areas: during seed production and during sprout production. Section 3 of this Code outlines several steps in the production of seeds where the application of GAP is aimed at preventing microbial pathogen contamination of seeds. Section 8 of this Code describes the various steps in the sprout production, including antimicrobial treatment of seeds, and provides good hygienic practices aimed at preventing the introduction of microbial pathogens and minimizing their potential growth. Antimicrobial treatment of seeds is one of various steps in the overall approach to minimize the risk associated with sprouts. A combination of steps, including antimicrobial treatment, is necessary in order to produce a safer product. During sprout production, the antimicrobial treatment step is aimed at reducing potential contaminants and the good hygienic practices at preventing the introduction of microbial pathogens and minimizing their potential growth. Sprout manufacturers must be aware that the degree of control in these two areas has a significant impact on the safety of sprouts.

The recommendations of this code do not guarantee the production of safe sprouts; rather, they provide a sound basis for risk mitigation and the hygienic production of sprouts. The scientific literature proposes antimicrobial treatments for seeds which can achieve different levels of pathogen reduction and minimize the risks associated with sprouted seeds. There is currently no treatment available that can guarantee pathogen free seeds. Much research is on-going to find efficient antimicrobial treatments which would provide sufficient pathogen reduction on seeds.

This Code is subject to change as additional scientific information becomes available on safe sprout production.

2. Scope and Definitions

2.1 Scope

This code addresses good agricultural practices (GAP) and good hygienic practices for the production of sprouted seeds that may be consumed raw. It sets out specific recommendations for the production of sprouts and general recommendations for the growing of seeds destined for sprout production.

2.2 Definitions

For the purpose of this Code, the following expressions have the stated definitions:

Agricultural inputs:
any incoming material (e.g., fertilizers, water, agricultural chemicals, etc.) used for the production of seeds.
Contamination:
the transfer of harmful substances or disease-causing microorganisms to sprouts by hands, food-contact surfaces and utensils that touch contaminated seeds and sprouts.
Cross-contamination:
contamination of seeds or sprouts by direct or indirect contact with material from an earlier stage of the process. A regulated process flow and good employee practices will minimize chances of cross-contamination occurrences.
Food contact surface:
any equipment or utensil, which normally comes in contact with the food product or surfaces normally in contact with the product.
Good Agricultural Practices (GAP):
refer to the general practices used in the planting, growing, harvesting, sorting, packing, storage and transportation of seeds which will reduce and minimize the risks of microbial, chemical and physical contamination.
Hazard Analysis Critical Control Points (HACCP):
a worldwide recognized, science based, systematic and preventive approach to food safety that addresses biological, chemical and physical hazards by anticipating and preventing, rather than by inspecting finished product.
Microorganisms:
include yeasts, moulds, bacteria, viruses and parasites. When used as an adjective the term "microbial" is used.
Potable water:
water which meets the requirements of the "Guidelines for Canadian Drinking Water Quality" published by Health Canada and any applicable provincial requirements.
Pre-packaged product:
as per the Food and Drugs Act, any food that is contained in a package in the manner in which it is ordinarily sold to or used or purchased by a person.
Refrigeration:
means exposure to a temperature of 4°C or less, but does not mean frozen (Food and Drug Regulations, B.27.001).
Sanitizing:
the application of heat or chemical treatments to destroy or substantially reduce the number of microorganisms that have the potential to cause adverse health effects.
Seed distributor:
any person responsible for the distribution of seeds (handling, storage and transportation) to sprout manufacturers. Seed distributors may deal with single or multiple seed producers and can be producers themselves.
Seed producer:
any person responsible for the management of activities associated with the primary production of seeds including post harvest practices.
Seed lot:
a quantity of seeds produced and handled under uniform conditions with as little variation as possible (e.g., seeds grown under similar agricultural practice, on the same land and harvested during the same period).
Spent irrigation water:
the water that has flowed over and through the sprouts.
Sprout lot:
a quantity of sprouts produced and handled under uniform conditions with as little variation as possible and harvested on the same day (e.g., sprouts produced from a single seed lot, germinated, grown and harvested at the same time using the same disinfection and growing methods and type of equipment).
Sprout manufacturer:
any person responsible for the management of the activities associated with the production of sprouted seeds.
Sprouted Seed:
any seed that has been sprouted for human consumption. This includes seeds grown in soil.

3. Seed Production

Microbial and chemical contamination may occur during the cultivation and harvesting of seeds in fields or during storage and transportation. The safety of sprouts is highly influenced by the degree of preventive measures used on farm to avoid contamination of seeds. Seeds used for sprout production should be produced using GAP at all stages during the planting, growing, harvesting, cleaning, storage and transportation. Sprout manufacturers should prescribe seed producers to adopt GAP and provide evidence that the product was grown according to specifications. The general aspects of GAP to minimize the risk of contamination of seeds for spout production include:

3.1 Land usage

Whenever possible, potential sources of contamination from the environment should be identified. In particular, primary production should not be carried out in areas where the presence of potentially harmful substances would lead to an unacceptable level of such substances in or on seeds after harvest.

Where possible, seed producers should evaluate the previous uses of the sites (indoor and outdoor) as well as adjoining sites in order to identify potential microbial, chemical and physical hazards. The potential for other types of contamination (e.g., from agricultural chemicals, hazardous wastes, etc.) should also be considered.

To the extent possible, steps should be taken to prevent the access of farm and wild animals to the sites to avoid potential faecal contamination of the soil and the risk of contaminating the crop. Runoff or wind contamination from intensive livestock operations and flooding by contaminated water sources should also be considered.

3.2 Natural fertilizer

Composting and other treatments may reduce but may not eliminate pathogens in manure. It is particularly important to prevent microbial contamination during the production of seeds because of the potential for pathogens to grow during the sprouting process. Consequently, manure, bio solids and other natural fertilizers should only be used when they have undergone treatments or undergone environmental conditions which achieve a high level of pathogen reduction.

3.3 Agricultural water

Water used for irrigation and other agricultural uses is a potential source of microbial contamination. Seed producers should evaluate the source of water used on farm (well, open canal, reservoir, reused irrigation water, municipality, rivers, lakes, ground water, etc.), monitor its safety and control potential sources of contamination. Water known or suspected to be contaminated with animal or human waste shall not be used.

3.4 Chemical Control

Seed producers and distributors should only use chemicals for agricultural purposes and post-harvest treatments acceptable for seeds intended for sprout production. These chemicals should be used according to manufacturer's instructions for the intended purpose. Their use must not result in exceeding Maximum Residue Limits in sprouts. Seed producers and distributors should keep records of chemical applications (agricultural or post-harvest chemical used, rate and date of application, etc.)

3.5 Worker hygiene

Hygiene and health requirements should ensure that people who come directly or indirectly into contact with seeds do not contaminate them. People known or suspected to be carriers of a disease or illness should not be allowed access to areas of the fields or indoor premises where there is a potential for contaminating seeds for sprout production. To ensure good personal hygiene, seed producers should provide toilets and hand washing facilities easily accessible to all workers who come directly into contact with seeds.

3.6 Harvesting

Harvesting equipment should be adjusted to minimize soil intake and should be cleaned from any debris or earth before harvesting. Handling equipment (augers, conveyors, etc.) should be cleaned and inspected. Transport trucks, wagons, etc. should be cleaned and sanitized if used to haul manure and soil. Storage bins, totes, etc. should be clean and be bird and rodent proof or stored in a rodent controlled facility.

Diseased or damaged seeds which could be susceptible to microbial contamination shall not be used for sprout manufacture. Seed lots intended for sprouting should be segregated from product to be used as animal feed (e.g., for hay production).

3.7 Conditioning

Seeds for sprouting should be free to the extent possible from foreign matter including soil, insect fragments, bird and rodent droppings, metal and glass fragments. Conditioning utilizes a variety of equipment to remove soil, weed seeds and other debris from seeds. Conditioning should be carried out in a hygienic manner employing practices that minimize potential sources of contamination.

3.8 Packaging

3.9 Transportation and storage

Seeds should be packaged in bags or containers that are impermeable to contamination during storage and transportation. Containers, vehicles, and storage facilities should be cleaned and sanitized before use. At all times, seeds, equipment, storage bins and shipping bags should be protected from rodents and birds with a complete pest control program that includes monitoring, eradication, cleaning, sanitation and record keeping.

3.10 Analyses, documentation and records

Seed distributors should analyse each lot for the presence of microbial pathogens of concern such as Salmonella and E. coli O157:H7 using internationally accepted analytical methods. Microbial analysis of seeds may help identify highly contaminated lots. Seed producers and sprout manufacturers must be aware that negative results do not guarantee pathogen free seeds because of analytical and sampling limitations. It is important to use random sampling techniques, sufficient sample sizes and sub sample numbers to represent the lot as best as possible.

Lots of seeds for which positive results are obtained shall not be used for sprout production. Other lots which were produced under similar conditions (e.g., on the same sites or with the same agricultural inputs) which present a similar hazard shall not be used for sprouting. These lots should be held and detained until they are disposed of properly.

Seed producers should keep current all records on agricultural activities such as the site of production, suppliers' information on agricultural inputs, lot numbers of agricultural inputs, irrigation data, agricultural chemical and fertilizer usages, water quality data, cleaning schedules for premises, facilities, equipment and containers, and details of disposition of rejected lots. Records shall be retained for a minimum of five years.

3.11 Trace-backs and recalls

Producers of seed for sprout production must ensure that trace-back records and recall procedures are in place to effectively respond to health risk situations. Procedures must enable the complete and rapid recall of any implicated seed lots and provide detailed information to assist in the identification and investigation of any contaminated seeds and sprouts. The following should be adopted:

4. Establishment for Sprout Production

4.1 Premises

The internal design and layout should permit good hygienic practices during production, including protection against cross-contamination between operations and during cleaning and sanitation of utensils and equipment. It is important to disinfect seeds in areas separated from other process areas to minimize cross-contamination. Storage, seed disinfection, germination and packaging areas should be physically separated from each other. The sprout processing facility should be fully protected from outside contaminants.

Floors should be smooth, non porous, impervious to water and properly drained. Walls, doors and ceilings should be smooth, non-porous, non-chipping and impervious to water. Doors should be close fitting, and self closing where appropriate. Light bulbs and fixtures should be protected to prevent contamination of sprouts in case of breakage.

4.2 Equipment

All equipment and utensils used during sprout production should be cleaned, rinsed and sanitized between batches and as frequently as required during production, according to a written sanitation program. Sanitizers should be rinsed from the equipment and utensils unless otherwise instructed by the manufacturer's directions. Equipment should be visually inspected to determine adequacy of cleaning and records of the sanitizing treatments and inspections should be kept.

Equipment and containers coming in contact with sprouts should be made of materials which have no leaching toxic effect. Equipment and containers should also be designed and constructed to ensure that they can be adequately and easily cleaned, sanitized and maintained. Specific hygienic requirements should be identified for each piece of food-contact equipment.

Containers for waste, by-products and inedible or dangerous substances, should be identified, suitably constructed, and where appropriate, made of impervious material. Where appropriate, such containers should be stored in a manner to prevent malicious or accidental contamination.

4.3 Water quality

Water shall meet the requirements of Health Canada's Guidelines for Canadian Drinking Water Quality. Water should be analysed by the manufacturer at a frequency adequate to confirm its potability. Municipal water should be analysed semi-annually and other water sources on a monthly basis. Records of potable water quality checks should be kept. Water treatment chemicals, where used, should be those found in the Reference Listing of Accepted Construction Materials, Packaging Materials and Non-Food Chemical Products published by the CFIA.

Sprout manufacturers should have contingency plans in place to deal with provincial orders to boil water and unsatisfactory water analyses.

4.4 Air quality

Adequate ventilation should be provided to prevent condensation, dust, and to minimize entry of contaminated air. Ventilation systems should be constructed to avoid air flow from contaminated to clean areas and designed to be adequately maintained and cleaned. Ventilation openings should be equipped with close-fitting screens or filters to reduce the risk of contaminated air intakes.

5. Sanitation and Pest Control

5.1 Sanitation program

Cleaning and sanitation programs should ensure that all equipment and all parts of the establishment are clean. Cleaning and sanitation programs should be periodically reviewed and modified as needed.

5.2 Pest control program

5.3 Waste management

Suitable provision must be made for the storage and removal of waste. Waste must not be allowed to accumulate in seed and sprout handling and storage areas or the adjoining environment. Storage areas for waste should be separated from the plant, kept clean and all waste containers should be properly labelled.

6. Personal Hygiene

Hygiene and health requirements should be followed to ensure that people coming into direct or indirect contact with seeds before, during and after germination are not likely to contaminate the product. All plant personnel and visitors, where appropriate, should wear protective clothing and adhere to the personal hygiene provisions in this section.

6.1 Personal hygiene and sanitary facilities

Hygienic facilities and toilets must be available to personnel so as to maintain an appropriate degree of hygiene and to avoid product contamination.

6.2 Sanitizing stations

Pathogen contamination after seeds have been disinfected could be due to employee handling.

6.3 Health status

People known to be or suspected of being a carrier of a disease or illness likely to be transmitted through food should not be allowed access to areas of indoor premises where there is a likelihood of directly or indirectly contaminating sprouts. Any person so affected should immediately report the illness or symptoms of illness to management. Employees having open cuts, wounds or sores should not handle food or food contact surfaces unless the injury is completely protected by a secure waterproof covering (e.g., rubber gloves).

6.4 Cleanliness and personal behaviour

7. Training

7.1 Awareness and responsibilities

Food handlers should be trained in personal hygiene and hygienic handling of food such that they understand the precautions necessary to prevent the contamination of sprouts.

7.2 Management and supervision

Periodic assessments of the effectiveness of training and instruction programs should be made as well as routine supervision and checks to ensure that procedures are being carried out effectively. Managers and supervisors for sprout manufacturing should have the necessary knowledge of food hygiene principles and practices to be able to judge potential risks and take the necessary action to remedy deficiencies.

8. Control of Sprouting Operations

8.1 Control of food hazards

Sprout manufacturers should control food hazards through a system based on Hazard Analysis and Critical Control Point (HACCP) principles. They should:

A Hazard Analysis and Critical Control Point (HACCP) type program will reduce the risk of unsafe food by taking preventive measures to assure the safety and suitability of food at an appropriate stage in the operation by controlling food hazards.

8.2 Prevention of cross-contamination

During sprout production, effective measures should be taken to prevent cross-contamination of seeds and sprouts. To prevent cross-contamination, sprout manufacturers should adhere to the recommendations presented in this code and the following:

8.3 Incoming seeds

8.3.1 Specifications

8.3.2 Control of incoming seeds

Each bag should be examined at its arrival to minimize the potential for introducing obvious contaminants into the establishment. If certificates of analysis are not provided by seed producers or distributors or if sampling and analyses are not done according to section 3.10 of this code, sprout manufacturers should analyse the seed lots for the presence of microbial pathogens of concern according to section 3.10 of this code.

8.3.3 Seeds storage

The storage area for seeds should be clean, dry, protected against pests and separate from the rest of the facility. It should not be used to store equipment, chemicals or personal items.

8.4 Specific steps in sprout production

All steps involved in antimicrobial treatment for seeds (e.g., initial rinse and disinfection) should be carried out in an area separate from the germination and packaging areas and designed to avoid contamination of sprouts by non disinfected seeds or chemical disinfectants.

8.4.1 Initial rinse

The seeds should be rinsed thoroughly before the antimicrobial treatment to remove dirt and increase the efficiency of the antimicrobial treatment.

8.4.2 Antimicrobial treatment for seeds

If seeds for sprouting have been grown under GAP and stored and transported in closed containers, the likelihood of being contaminated with pathogenic bacteria is minimized but not eliminated. Seeds should undergo an antimicrobial treatment to reduce the potential for pathogenic microorganisms. There is currently no treatment available that can guarantee pathogen free seeds. An antimicrobial treatment for seeds that can achieve a minimum 3 log reduction of the microbial pathogens of concern should be considered. Examples of such treatments are the use of 2,000 ppm of calcium hypochlorite or sodium hypochlorite for 15-20 minutes or 6-10% hydrogen peroxide for 10 minutes. Other antimicrobial treatments for seeds may be evaluated by the Food Directorate, Health Products and Food Branch, Health Canada, if enough data is provided.

During the antimicrobial treatment, sprout manufacturers should adhere to the following:

8.4.3 Rinse after Antimicrobial treatment

The seeds must be thoroughly rinsed with potable water after the antimicrobial treatment. Rinsing should be repeated sufficiently with potable water to eliminate disinfectant.

8.4.4 Pre-germination soak

Soaking is often necessary to improve germination. When soaking, the sprout manufacturer should adhere to the following:

8.4.5 Germination

During germination, it is critical to keep the environment and equipment clean to avoid potential contamination. All equipment should be cleaned and sanitized before each new batch.

8.4.6 Harvesting

All equipment should be cleaned and sanitized before each new batch. Harvesting should be done with cleaned and sanitized tools dedicated for this use.

8.4.7 Final rinse and cooling

A final water rinse will remove hulls and may reduce microbial contamination on sprouts. Cold water will lower sprout temperature and slow down potential microbial growth. When the final rinse is being carried out, the following should be adopted:

8.4.8 Bulk cooling

8.5 Packaging

Packaging design and materials should provide adequate protection for sprouts to minimize contamination, prevent damage, and accommodate proper labelling. Packaging materials must be clean, non-toxic and pose no threat to the safety and suitability of sprouts under the specified conditions of storage and use. There should be no unnecessary delays between harvesting and packaging.

8.6 Labelling

Prepackaged sprouts should be labelled with clear instructions to enable the next person in the food chain to handle, display, store or use the product safely.

8.7 Storage of finished product

The cold storage room used for sprouts should allow for adequate maintenance and cleaning; prevent pest access and harbourage; and consistently provide an environment which minimizes microbial growth (e.g., by temperature control and air circulation).

8.8 Analysis of spent irrigation water and finished product

Sprout manufacturers should have a sampling plan to ensure the consistent collection of samples in an appropriate manner. Spent irrigation water is the water that has flowed over and through the sprouts and is a good indicator of the types of microorganisms in the sprouts themselves. It should be analysed for microbial pathogens of concern by collecting a representative sample from each production lot or batch. Finished product samples may also be collected and analysed.

Refer to Appendix A for guidance on sample collection and testing of spent irrigation water and sprouts.

8.9 Transportation

Transportation vehicles used for sprouts should permit adequate maintenance and cleaning and provide an environment which minimizes microbial growth.

9. Documentation and Records

Written records that accurately reflect product information and operational controls should be available to demonstrate the adequacy of the manufacturing activities. Records should be available on demand.

10. Trace-Backs and Recalls

Sprout manufacturers should ensure that effective trace-back and recall procedures are in place to respond to food safety hazards. They should enable the complete and rapid recall of any implicated lot of sprouts from the market and provide detailed information to assist in the investigation of any identified sprout contamination. Written recall procedures should include the following:

Appendix A: Guidance on Sample Collection and Testing of the Spent Irrigation Water and Sprouts

Microbial testing of spent irrigation water is considered to be one of the most practical and acceptable testing techniques currently available. Health Canada recommends that sprout manufacturers regularly test the spent irrigation water, because water that has flowed over and through the sprouts is a good indicator of the types of microorganisms in the sprouts themselves, including pathogens of microbial concern (Salmonella spp., E. coli O157:H7). Sprouts should not be tested in place of spent irrigation water unless the production methods make it impossible to test the spent irrigation water. However, the recommendation to test spent irrigation water does not preclude additional testing of sprouts (either sprouts collected during production or finished product). Representative samples should be collected from each production lot and analysed for microbial pathogens of concern.

Sampling Equipment and Containers

Equipment and containers used to collect samples should be clean and sterile. They may be purchased pre-sterilized or, alternatively, they may be sterilized at 121°C (250°F) for 30 minutes in an autoclave, prior to use. Heat-resistant, dry materials may be sterilized in a dry-heat oven at 140°C (284°F) for 3 hours. Once sterilized, the sampling equipment and containers should be protected from contamination at all times before and during use. Ensure that the used sampling equipment, containers and the collected samples do not contaminate remaining sterile equipment and containers.

The type of sample containers to be used depends on whether spent irrigation water or sprout samples are being collected. Containers may include pre-sterilized plastic bags, bottles, tubes, cups and flasks. They should be dry, leak-proof, wide-mouthed, and of a size suitable for the samples. Containers should also seal properly to ensure the integrity of the sample. The containers should be properly labelled prior to collecting the sample.

When to Sample

Samples of spent irrigation water can be collected as early as 48 hours after the start of sprouting. If the seeds are pre-soaked (e.g., soaked in water for a short time and then transferred to growing units for sprouting), include the pre-soak time. Early results will allow the sprout manufacturer to take corrective actions sooner, thus minimizing the potential for one lot of sprouts to contaminate other lots.

Procedures for Sample Collection

Sample collection of spent irrigation water and sprouts should be done on site by trained personnel. Aseptic sampling procedures should be used to avoid contaminating the sample and the product being sampled.

Personnel should wear a clean lab coat, hair net and sterile gloves. Hands should be washed immediately prior to putting on sterile gloves. The sterile gloves should be put on in a manner that does not contaminate the outside of the glove. During sample collection, hands should be kept away from the mouth, nose, eyes and face. After sample collection, the gloves should be properly discarded.

The sterile sample container should be opened only sufficiently to allow for the sample to be collected. The sample should be placed directly in the container. Once the sample is collected, it should immediately be closed and sealed. If collecting samples in a container with a lid, the lid should not be completely removed. The lid should not be held separately or placed on a counter.

The sample container should be filled no more than ¾ full to prevent overflow. The air from the container should not be expelled when sealing, particularly for plastic bags.

Once collected, the samples should be delivered to the laboratory promptly. The sample should be kept at an appropriate temperature, preferably between 0 and 4°C (32° to 40°F). To avoid cross-contamination from melting ice, sealed coolant packs should be used.

Pooling samples from different sprout lots may reduce the number of lab analyses to be performed, however if a presumptive positive is found, all sprouts lots represented by the pooled sample are suspect. The suspect sprout lots should either be discarded or each sprout lot should be analysed separately to determine which lot(s) is (are) contaminated.

Sample Size

The volumes given below for spent irrigation water and sprouts represent a sufficient sample size to test for the presence of the microbial pathogens of concern (i.e., Salmonella spp., and E. coli O157:H7).

A. Spent Irrigation Water

One (1) litre of water should be aseptically collected as the water leaves a drum or tray(s) during the irrigation cycle. Spent irrigation water samples should be collected directly into clean, sterile, pre-labelled containers.

Drums

One (1) litre of spent irrigation water may be collected from the drum.

Trays with Common Trough

One (1) litre of spent irrigation water may be collected at the common trough.

Trays with no Common Trough

If there is no common trough, spent irrigation water samples from individual trays should be collected and pooled. If the tray is large, spent irrigation water samples from different areas of the tray should be collected.

When Ten (10) or fewer trays make up a production lot, approximately equal volumes of spent irrigation water should be collected from each of the 10 trays to make a total sample volume of one (1) litre. For example:

When there are Ten (10) or more trays, collect ten (10) spent irrigation water samples throughout the entire production lot. For example: if there are 20 trays in a production lot, collect samples from every other tray in the rack, moving from top to bottom, side to side, and front to back.

B. Sprouts

Five (5) sample units of approximately 200 grams each should be aseptically collected from different locations in the drum or growing trays, to ensure the sample collected is representative of the lot. The sample units should be collected throughout the entire production lot (e.g., from top to bottom, side to side, and front to back of the drum or trays). Each 200 gram sample unit should be placed directly into individual clean, sterile, pre-labelled containers.

Microbial Testing Procedures

All microbial testing for pathogens should be conducted in an external, certified, independent laboratory, and meet the following criteria:

The testing procedures described below can be used to obtain results as simply and quickly as possible on the presence or absence of the microbial pathogens of concern (i.e., Salmonella spp. and Escherichia O157:H7). These methods are described in the Health Canada (HC) Compendium of Analytical Methods

Please keep in mind that seasonal or regional differences in water quality, type of seed being sprouted, and variations in sampling and analytical conditions may all impact on the effectiveness of the screening tests.

Test Kits

Escherichia coli O157:H7:

  1. MFLP-87 VIP EHEC. Biocontrol Systems, Inc., Bellview, WA.
  2. MFLP-94/95 Reveal  E. coli O157:H7, Neogen Corp., Lansing, MI.
  3. MFLP-91 Tecra UVA method for  E. coli O157:H7.
  4. Any other methods listed in the Compendium for E. coli O157:H7.

Salmonella spp.:

  1. MFHPB-24 Vidas SLM method, Biomerieux, Montreal.
  2. MFLP-96 Reveal kit for Salmonella.
  3. MFLP-97 Alert kit for Salmonella.
  4. MFLP-35 Tecra VIA for Salmonella.
  5. Any other methods listed in the Compendium for Salmonella spp.

General Laboratory Instructions

Follow instructions in each method.

Dividing Samples into Sample Units for Analysis

Spent Irrigation Water

Total of one (1) L of spent irrigation water should be collected. Two (2) 100 ml sample units should be analysed for the presence of E. coli O157:H7. Two (2) 375 ml sample units should be analysed for the presence of Salmonella spp. Any unused portion of spent irrigation water should be stored under refrigeration pending completion of the analysis.

Sprouts

Total of five (5) sample units of 200 g of sprouts should be collected. For each sample unit, one 25 g sample unit should be analysed for the presence of E. coli O157:H7 and one 25 g sample unit should be analysed for the presence of Salmonella spp. Unused portions of the sprout sample units should be stored under refrigeration pending completion of the analysis.

When Pathogens of Microbial Concern are Detected

When spent irrigation water or sprout samples are found to be positive for Salmonella spp. or E. coli O157:H7, this is considered to be a health risk and in violation of Sections 4 & 7 of the Food and Drugs Act. The sprout manufacturer should notify the CFIA immediately.

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