Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 27, 2012
Publication Date: April 1, 2013
Citation: Chmielewski, R.A., Beck, J.R., Swayne, D.E. 2013. Evaluation of the U.S. Department of Agriculture's egg pasteurization processes on the inactivation of high pathogenicity avian influenza virus and velogenic Newcastle disease virus in processed egg products. Journal of Food Protection. 76(4):640-645. DOI: 10.4315/0362-028X.JFP-12-369. Interpretive Summary: The United States produces and exports a large amount of egg products. Although the U.S. is normally free of high pathogenicity avian influenza (HPAIV) and Newcastle disease viruses (NDV), concern about contamination of egg product with these viruses has in the past resulted in restrictions on trade. Because these egg products are normally pasteurized, this study was performed to see if standard salmonella pasteurization times and temperatures would be effective at inactivating viruses in sugared, fortified, salted and plain egg product at various times and temperatures of heat processing. The USDA pasteurization standard for various egg products are based on a reduction of 5 log10 cells of salmonella. The standard pasteurization processes were used to inactivate HPAIV and vNDV and to determine if these pasteurization processes would adequately inactivate 5log10 viruses/ml in the liquid egg products. The information suggests that the pasteurization processes inactivated greater than 5 log10 HPAIV/ml in four of five egg products while for the vNDV virus pasteurization for sugared and salted egg yolk was inadequate at the higher temperature-shorter time process but adequate at lower temperature-longer time process.
Technical Abstract: High pathogenicity avian influenza virus (HPAIV) A/chicken/Pennsylvania/1370/1983 (H5N2), and velogenic Newcastle disease virus (vNDV) AMPV-1/California/212676/2002 were inoculated into various egg products then heat treated at various temperatures for 0 to 30 min to determine thermal inactivation properties based on standard USDA pasteurization criteria for the specific product. HPAIV had D61.1 of 0.23 min and D62.2 of 0.14 min for fortified egg yolk, D62.2 of 0.05 min and D63.3 of 0.02 min for 10% sugared egg yolk, D60 of 0.06 min and D61.1 of 0.03 min for plain egg yolk, D62.2 of 0.06 min and D63.3 of 0.04 min for 10% salted egg yolk, and D60 of 0.56 min and D61.1 of 0.2 for homogenized whole egg. vNDV was more resistant than HPAIV to thermal inactivation from pasteurization processes. vNDV had D61.1 of 1.1 min and D62.2 of 0.53 min for fortified egg yolk, D62.2 of 1.1 min and D63.3 of 1 min for 10% sugared egg yolk, D60 of 0.86 min and D61.1 of 0.5 min for plain egg yolk, and D62.2 of 1.0 min and D63.3 of 0.87 min for 10% salted egg yolk. Egg substitute with fat does not have standard USDA pasteurization criteria, but the D59 was 0.75 min, adequate to inactivate 5log10 of vNDV in less than 4 min. For HPAIV and vNDV, the pasteurization processes for fortified, sugared, plain and salted egg yolk, and homogenized whole egg (HPAIV only) products resulted in a greater than 5 log10 reductions in virus at the lower temperature/longer times of approved USDA pasteurization processes. In addition, a greater than 5 log10 reduction of HPAIV was also demonstrated for the five products at the higher temperatures/shorter time of approved USDA pasteurization processes while vNDV virus was adequately inactivated in only fortified and plain egg yolk products. For the salted and sugared egg yolk products, an additional 0.65 and 1.6 min. of treatment, respectively, at 63.3 ºC would be necessary to inactivate 5 log10 of vNDV.