Rapid detection of Salmonella in foods using a combination of SPRINT™, MSRV™ and Salmonella Latex Test™

Abstract

A new procedure for rapid detection of Samonella in foods, based on the combination of SPRINT™, MSRV™ and Salmonella Latex Test™, was evaluated. SPRINT™ is a system to reduce the pre-enrichment and selective enrichment steps to 24 hours. MSRV™ is a semi-solid selective media for detection of motile Salmonella. Salmonella Latex™ is a rapid latex agglutination test for Salmonella. Using the three systems in combination, the total time for detection of Salmonella in a food sample is 48h. Evaluations were performed in artificially contaminated ready-to-eat baby-foods and raw Brazilian sausages (linguica) containing no added microorganisms. The BAM conventional culture procedure was used as reference method. The study with baby foods indicated that the new procedure had good sensitivity (89%) and specificity (100%), without cross-reactions with Enterobacteriaceae. However, when applied to naturally contaminated foods, the performance was poor chi square (x2 = 5.062, α ≥ 0.05) and Kappa-Cohen agreement (K = 0.171, p = 0.089) indexes indicated that the differences between results given by the two procedures were significant and the correlation between them was low.