Effect of four presumptive coliform test media, incubation time and product inoculum size on recovery of coliforms from dairy products

The need to consider the interrelationship of relevant procedural parameters in media comparison studies has been shown. In this study, the influence of media-type on recovery of coliforms from dairy products was found to be of less importance than the effects of incubation time and inoculum size. Statistically significant media-type effects were found, however, and these contrasted with the observations of other workers in that bile-salt-based media performed better than chemically-defined media. These findings indicate that media studies too specifically designed may yield conclusions with limited range of application.