Decision Document for Use of Heat Treatment to Pasteurize Eggs In-Shell

 Health Canada has notified National Pasteurized Eggs Inc. that it has no objection to the use of in-shell pasteurized eggs that have been treated with heat treatment using a computer-controlled thermal process which will achieve a minimum 5-log reduction of Salmonellaspp. The Department conducted a comprehensive assessment of these in-shell pasteurized eggs according to its Guidelines for the Safety Assessment of Novel Foods. These Guidelines are based upon internationally accepted principles for establishing the safety of novel foods.

Background:

The following provides a summary of the notification from National Pasteurized Eggs Inc. and the evaluation by Heath Canada and contains no confidential business information.

1. Introduction

This Novel Food Information document has been prepared to summarize the opinion regarding the subject product provided by the Food Directorate, Health Products and Food Branch, Health Canada. This opinion is based upon the comprehensive review of information submitted by the petitioner according to the Guidelines for the Safety Assessment of Novel Foods.

Heat treatment is used to pasteurize eggs in their shells using a computer-controlled thermal process based on a statistical model derived from challenge studies. The heat treatment achieves a minimum 5-log reduction of Salmonellaspp. The eggs are heat treated in a water bath containing potable water containing hydrogen peroxide to control water quality, and the water quality is monitored. Eggs leaving the pasteurizer are allowed to slowly cool, and are sprayed with a liquid sanitizer and disinfectant, and then sealed with hot wax. The eggs are then dried, packaged and held under refrigeration for distribution to retail. In-shell pasteurized eggs will be offered for sale under refrigeration, alongside regular shell eggs and pasteurized egg products. After the heat treatment, the egg contents remain liquid. 

The safety assessment performed by Food Directorate evaluators was conducted according to Health Canada's Guidelines for the Safety Assessment of Novel Foods. The assessment considered: the heat treatment process, the nutritional composition of both heat-treated and untreated products, the potential for the heat treatment process to result in the presence of any toxic compounds within each product, and the microbiological safety of the finished in-shell pasteurized eggs.

The Food Directorate has a legislated responsibility for the pre-market assessment of novel foods and novel food ingredients as detailed in Division 28 of Part B of the Food and Drug Regulations (Novel Foods). Eggs pasteurized in their shells by heat treatment are considered novel foods, as per B.28.001, as they have been manufactured by a process that has not been previously applied to that food and causes the food to undergo a major change with regard to microbiological safety.

2. Development of the novel food

National Pasteurized Eggs Inc. has provided information describing the methods and parameters used and the potential effects of the heat process on the shell eggs.

In the United States, shell eggs are sourced from farms using the National Poultry Improvement Program Standards and all meet U.S. Grade A or better. Eggs are maintained under HACCP procedures at both the farm and pasteurization facility. Eggs to be processed are held at room temp for less than 36 hours and then are stored at or under 45F. NPE operates facilities under strict HACCP, with egg storage temperatures as a CCP (Note that in Canada, these specifications will be slightly different, as outlined in the Microbiological Assessment below).

Potable water from the municipality is used in the heat pasteurizer, and the water testing results from the municipality are monitored.  In addition, NPE tests the water in the pasteurizer twice daily.  The water bath contains hydrogen peroxide to control microbial growth that might occur due to egg contents released from eggs whose shells break during pasteurization.  When the shell eggs enter the pasteurizer, a computer-controlled thermal process, based on a statistical model derived from challenge studies, achieves a minimum 5-log reduction of Salmonella spp.  For refrigerated eggs, the eggs are held for approximately 52 minutes at 56.6°C.  The water temperature is monitored at 80 locations in the pasteurizer, and the water is agitated to maintain even temperature distribution. The computer-controlled process ensures that the minimum 5-log reduction is met by adjusting any temperature fluctuation that may occur in the water bath.

Eggs leaving the pasteurizer are allowed to slowly cool, and are visually inspected to remove broken eggs. The pasteurized eggs are sprayed with a liquid sanitizer and disinfectant, sealed with hot wax and then stamped to identify them as pasteurized.  The eggs are then dried, packaged and held under refrigeration for distribution to retail.  In-shell pasteurized eggs will be offered for sale under refrigeration, alongside regular shell eggs and pasteurized egg products.

3. Dietary Exposure

It is expected that these in-shell pasteurized eggs will be consumed at a similar rate as pasteurized egg products. Some consumers may choose to replace regular shell eggs with this product. The overall consumption of pasteurized egg products in general might increase because of the ability to use these products and prepare them in a way that will give them the same appearance as shell eggs. Furthermore, foodservice and institutional settings might choose these pasteurized products to replace shell eggs to decrease food safety risks.

4. Chemistry

There are four instances where one or more chemicals are used during or following the pasteurization step. First, a 35% solution of hydrogen peroxide (H2O2) is added to the pasteurizer water bath that is used to pasteurize the eggs. The maximum concentration of the H2O2 in the water bath would be 900 ppm, although the concentration is to be maintained at 400-500 ppm. Following the pasteurization step, the eggs are sprayed with a mixture of a quaternary ammonium solution (Vigilquat) and potable water. The pasteurized eggs are then coated with a hot wax preparation (Emulsion EC 30) and stamped with the letter “P” using a red ink formulation.

The hydrogen peroxide and Vigilquat are considered processing aids, in accordance with the Food Directorate’s Policy for Differentiating Food Additives and Processing Aids, if their use results in no or negligible residues in the finished food. The petitioner indicated, based on results from a hydrogen peroxide assay with a detection limit of 5 ppm, that no migration of the hydrogen peroxide into the eggs was detected. While there is no potable water rinse step following application of the Vigilquat solution, the petitioner claimed that there is no residual Vigilquat on the eggs. No data were provided to support this claim. However, the egg shell and membrane is expected to act as a type of functional barrier such that it is unlikely that non-negligible residues of the Vigilquat solution, when this solution is used as described in preparing pasteurized eggs, would end up in the egg as consumed. Therefore, BCS has not at this time identified a chemical food safety reason to object to the use of the hydrogen peroxide and Vigilquat, as described by the petitioner, if there are no chemical residues in the food to be consumed as a result of the use of these chemicals.

In 1998, the Bureau of Chemical Safety issued a letter of no objection for the use of Emulsion EC 30 as an egg coating “provided that there will be no resultant contamination of the treated shell eggs and the ingredients utilized in its manufacture are of appropriate food-grade quality.” Since the current formulation of this coating to be used on pasteurized eggs is comparable to the formulation of the product for which no objection was issued, BCS has no objection to the use of Emulsion EC 30 on pasteurized eggs under similar provisos to those specified in the letter of no objection from 1998.

No concerns from a chemical food safety perspective have been identified with respect to the formulation of the red ink product to be used to stamp a letter “P” on the pasteurized eggs. The three colours in this formulation (erythrosine, brilliant blue, and yellow orange (i.e. sunset yellow)) are already permitted for direct addition to various foods, and the ethanol and isopropanol in this product are permitted as carriers in egg marking inks. However, the petitioner may wish to verify with the supplier that the ethanol and isopropanol meet the specifications for these chemicals set out in the most recent edition of the Food Chemicals Codex as required by section B.01.045 of the Food and Drug Regulations and that the colours meet the regulatory requirements for colours set out in Division 6 of the Regulations.

The petitioner should be advised that food sellers are responsible for ensuring there is no violation of section 4 of the Food and Drugs  Act as a result of the use of chemicals in food manufacture.

5. Microbiology

The Petitioner has defined minimum quality specifications and storage conditions for incoming eggs to be pasteurized, to ensure that the pasteurization process that delivers a minimum 5-log reduction of Salmonellaspp. will be sufficient to render the eggs pasteurized and to meet the microbiological specifications for processed egg as specified in the Processed Egg Regulations.

The Petitioner has provided statistical and modelling data to support that the use of a computer-controlled thermal process will achieve a minimum 5-log reduction of Salmonella spp. Microbiological data was submitted supporting the 60 day refrigerated shelf-life of the in-shell pasteurized eggs.

The Petitioner has provided information regarding the control of water quality control to ensure the microbiological safety of the in-shell pasteurized eggs. To ensure the microbiological safety of the eggs, they are sealed while hot to prevent influx of any microbiological surface contaminants.

Based on the data provided, the Bureau of Microbial Hazards has no objection to the food use of eggs pasteurized in their shells with heat treatment, provided that:

• The computer-controlled thermal process achieves a minimum 5-log reduction of Salmonellaspp.;
• These products are labelled “Keep Refrigerated” and stored under refrigeration conditions at all times throughout the 60 day refrigerated shelf life;
• Under the Canada Agricultural Products Act, the Egg Regulations (C.R.C., c. 284), Part I:9(34) specify that “No eggs shall be pasteurized unless they are eggs graded Canada A”.;
• These products would be required to comply with the microbiological specifications of Part I, 4(3)h of the Processed Egg Regulations (C.R.C., c.290) and would therefore be required to be free of Salmonella spp. and other pathogenic organisms of human health significance. Part I 5(2) specifies that the product must have a coliform count of no more than 10 per gram and a total viable bacteria count of no more than 50,000 per gram. Although these products do not meet the definition of processed egg under the Egg Regulations, Health Canada considers that these products would be required to meet the microbiological specifications of processed eggs; these regulations are enforced by the Canadian Food Inspection Agency (CFIA).

6. Nutrition

The petitioner provided a nutritional comparison of liquid and pasteurized eggs and the certificate of analysis (COA) of the raw, pasteurized in-shell and 60 day old pasteurized egg. The COA  contained data on the following: proteins, total carbohydrates, vitamin A, vitamin C, calcium, iron, sodium, fatty acids (fatty acid profile), and sugar profile. However, an amino acid profile was not submitted.

The nutrients analysed by the petitioner in liquid eggs were not changed by the in-shell pasteurization process and the 60 days of storage. The amino acid profile of the eggs was not submitted by the petitioner. However, given the temperatures and times used for processing, we would not anticipate significant changes in the amino acids profile of the pasteurized eggs. Hank et al. (2001) used similar conditions for pasteurization, and observed no significant changes in protein content and digestibility or amino acid profile/free amino acids after processing or during the require storage period.

Based on the nutritional data submitted and reviewed, the Bureau of Nutritional Sciences has no objection to the sale of shell eggs pasteurized using the processing and storage conditions outlined by National Pasteurized Eggs Inc.

7. Toxicology

Based on the pasteurization process supplied by the petitioner, there would not be any chemicals produced as a result of the processing of the eggs. 

The chemicals used in this process are limited to the use of hydrogen peroxide (used in the pasteurizing water bath), the sanitizing wash (Vigilquat solution), the food grade wax (Egg Coating Emulsion EC 30) and the stamp ink. These were reviewed by the Food Additive Section and based on their evaluation they had no objection to the use of these food additives.

Based on the information provided by the petitioner and the evaluation by the Food Additive Section, there is no toxicological information Pre-market Toxicology Assessment Section (PTAS) needs to review for this submission. On this basis, PTAS has no objection to the proposal.

Conclusion:

Health Canada’s review of the information presented in support of the food use of eggs that have been pasteurized in-shell with heat treatment concluded that this use does not raise concerns related to safety. Health Canada is of the opinion that these products are as safe as other pasteurized egg products on the market. 

This opinion is solely with respect to the suitability of the products described above. It is the continuing responsibility of National Pasteurized Eggs Inc. to ensure that their products are in compliance with all applicable statutory and regulatory requirements. Any new information obtained in relation to these products which have potential health and safety implications should be forwarded to Health Canada for our consideration in order to ensure the continued safety and integrity of all foods available in the Canadian marketplace. The sale of a food which poses a hazard to the health of consumers would contravene the provisions of the Food and Drugs Act.

This Novel Food Information document has been prepared to summarize the opinion regarding the subject product provided by the Food Directorate, Health Products and Food Branch, Health Canada. This opinion is based upon the comprehensive review of information submitted by the petitioner according to the Guidelines for the Safety Assessment of Novel Foods.

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For further information, please contact:

Novel Foods Section
Food Directorate                                                          
Health Products and Food Branch                          
Health Canada, PL2204A1
251 Frederick Banting Driveway
Ottawa, Ontario K1A 0K9
novelfoods-alimentsnouveaux@hc-sc.gc.ca