A rapid heat-resistant technique for presumptive identification ofSalmonella on desoxycholate-citrate agar

A caprylate esterase chromogenic test, which was considered to indicate positivity in 5 minutes if a bright colour appeared on the filter paper inoculum site to which one colony had been applied, was used to test 534Salmonella, 535 other bacteria capable of growth on desoxycholatecitrate agar (DCA), and 517 non-lactose fermenting colonies from stool cultures on DCA. It was found to be 100 % sensitive forSalmonella, 99 % specific, and more accurate than either direct antiserum agglutination or a urease test in these respects. The test kit could be stored at room temperature.