Salmonella Detection in Foods: Present Status and Research Needs for the Future.

Standard cultural procedures generally require 4 to 5 d for presumptive evidence of Salmonella in foods. Attempts at greater method brevity have resulted in the use of selective enrichment cultures as test material for short immunological tests including fluorescent antibody (FA), enrichment serology (ES), enzyme-linked immunosorbent assay (ELISA), direct immunoenzyme (DI) and membrane filter-disc-immunoimmobilization (MFDI) assays. Nonimmunological tests such as the lysine-iron-cystine-neutral red (LICNR) broth and a C-dulcitol radiometric technique have also been applied to enrichment broth cultures. Sensitivity of short (4 to 6 h) incubation of selective enrichment broths has yet to be established. The need for rapid, cost-efficient preenrichment-dependent analytical schemes is clear. Investigations on the modification of the Limulus amoebocyte lysate (LAL) test to detect Salmonella cell wall antigens in preenrichment cultures or application of the ELISA, the hydrophobic-grid-membrane (HGMF) techniques or other rapid diagnostic tests to preenrichment cultures are indicated.