A note on the performance of Rappaport's medium, compared with Rappaport-Vassiliadis broth, in the isolation of salmonellas from meat products, after pre-enrichment.

Abstract

Salmonellas were isolated from meat products using a slightly modified Rappaport's enrichment medium (R25), Rappaport‐Vassiliadis procedure (Rappaport's broth containing 10 ml instead of 30 ml of Malachite Green solution and incubated at 43oC instead of 37oC), and Muller‐Kauffmann's tetrathionate broth. From 255 samples, 89 were found positive with the Rappaport‐Vassiliadis procedure, 83 with the R25 broth, whereas only 43 were positive with Muller‐Kauffmann broth. It is concluded that the R25 medium may be used as an alternative to the more effective Rappaport‐Vassiliadis broth when the only available incubation temperature is 37oC.