Salmonella Detection in Meat and Fish by Membrane Hybridization with Chromogenic/Phosphatase/Biotin DNA Probe

The hybridization specificity of a biotin labeled 1.8 kb HindIII DNA fragment was confirmed by colony hybridization with Salmonella and non‐Salmonella isolates. Culture conditions were then tested for the enrichment of salmonellae in foods with large populations of competitive flora. Different conditions of preenrichment and selective enrichment could be used for detecting low populations of salmonellae in foods. Enrichment using lactose combined tetrathionate (CTET) broth and Salmonella‐Shigella (SS) agar followed by spotting the suspected isolates on a nitrocellulose membrane [CETE → SS (S)] was better. As low as 1.6 × 10 0 salmonellae/g food could be detected.