Purpose: The purpose of the study was to evaluate performance of the ANSR Salmonella method for detection of Salmonella spp. in pasteurized egg products, including dried whole egg, dried egg white, frozen liquid egg yolk and liquid whole egg, in comparison to that of the reference culture method of USDA-FSIS.
Methods: For both the ANSR and reference methods, 20 test portions of each egg product were inoculated with Salmonella spp. at the level to produce fractional positive results, along with 5 high level samples and 5 uninoculated controls. The samples were held under conditions intended to simulate natural contamination with sub-lethally injured cells. Half of the test portions were analyzed by the ANSR method (for dried egg products, 1:10 dilution in PBS is necessary) after 24h enrichment and half by the reference procedure.
Results: All high level samples tested positive and all negative controls tested negative for each pasteurized egg product by both ANSR assay and reference method. At the fractional positive level, a total of 80 test portions were analyzed by each method. There were a total of 44 positive results by the ANSR assay and 47 by the reference procedures. There were no statistically significant differences in the number of positive results obtained with the ANSR and reference methods for any of the products tested as determined by probability of detection analysis.
Significance: ANSR® Salmonella is a rapid, reliable method for detection of Salmonella spp. in pasteurized egg products.