COMPARISON OF MODIFIED SALMONELLA‐TEK ENZYME IMMUNOASSAY AND MODIFIED GENE‐TRAK SALMONELLA ASSAY FOR RECOVERY OF SALMONELLA FROM SELECTED LOW‐MOISTURE FOODS

Abstract

ABSTRACTThe sensitivity of the original versus the modified Salmonella‐Tek enzyme immunoassay (EIA) was compared for recovery of Salmonella spp. from selected low‐moisture foods. Serial tenfold dilutions were inoculated into incubated post enrichment media (dilution‐to‐extinction approach). Results indicated no significant difference between the original and modified Salmonella‐Tek EIAs. A comparison of the modified Salmonella‐Tek EIA and the modified GENE‐TRAK Salmonella assay, using the same approach, also showed no significant differences.The effectiveness of the assays was then compared using a second approach (dry bulk inoculation). A lyophilized culture was inoculated into bulk food. Replicate 25‐g test portions were used in a 3‐way comparison of the effectiveness of the modified Salmonella‐Tek EIA, the modified GENE‐TRAK Salmonella assay, and the standard culture method approved by the Association of Official Analytical Chemists (AOAC) International and recommended in the Food and Drug Administration's Bacteriological Analytical Manual. Of 460 test portions examined, 307 gave positive reactions with the modified Salmonella‐Tek EIA, 298 with the modified GENE‐TRAK Salmonella assay, and 292 with the AOAC/BAM culture method.