A chromogenic agar medium, the SMID (Salmonella Detection and Identification) agar (bioMerieux, France), which detects the ability of Salmonella to acidify glucoronate and produce no β-galactosidase, was compared with another chromogenic medium, the Rambach agar, and a conventional medium, the MLCB agar, using 30 Salmonella isolates including 23 serovars and 130 strains other than Salmonella. Also, a comparative study was carried out with unpasteurized liquid eggs, minced chicken meats, and diarrheal specimens to isolate Salmonella. Although the SMID and Rambach agars were not as selective as the MLCB agar, the former two agars were more specific than the latter. In addition, the specificity of the SMID agar was shown to be higher than that of the Rambach agar on which some strains of serovars Typhi, Enteritidis, and Hadar of Salmonella produced unspecific coloreless colonies. The use of the SMID agar may markedly reduce the number of biochemical tests and times to achieve the identification of Salmonella.
As food distribution is done increasingly in a global scale, food borne pathogens also spread throughout the world rapidly. It is imperative that world hea1th regu1ation and food pathogen control are done in a global scale as well. The increasing popularity of ready-to-eat foods also will have animpact on the food regulation in the world. As refrigerated, ready-to-eat foods are to have extended shelf-lives, pychrotrohic pathogens will present larger problems, while less heated, closer to fresh products with present larger prob1ems, while less heated, closer to fresh products with shorter shelf-lives are a1so becoming more popular which necessitates the development of more rapid and sensitive assay methods for potential pathogens. Meanwhile, to prevent food borne illness, HACCP-type control practices are more strongly required. Federal government of the United States, both FDA and USDA, have proposed regulations based on HACCP approach in the recent months. New, more rapid and sensitive analytical methods for pathogens are being developed, a few examples of which are presented here including automated immunoassays such as VIDAS by BioMerieux Vitek and “riboprinting” as well as “PCR-based” methodologies developed by DuPont. It is noteworthy that many new analytical methods are being approved (and given official first action status) by AOAC.