Microbiological examination for dairy purposes. Part 3. Methods for detection and/or enumeration of specific groups of microorganisms. Section 3.9. Detection of Salmonella
British Standard (BS 4285: Section 3.9: 1987): 13
A method for detecting Salmonella in milk and milk products is specified, involving 4 stages: (i) pre-enrichment for 16-20 h at 37 degrees C in buffered peptone water; (ii) enrichment for 2 periods of 18-24 h in a tetrathionate medium at 43 degrees C and a selenite cystine medium at 37 degrees C; (iii) plating out on bismuth sulphite agar and on brilliant green/phenol red agar, XLD agar or hectoen enteric agar, with incubation for 20-24 or, if necessary, 40-48 h at 37 degrees C; (iv) biochemical and serological tests to confirm presumptive Salmonella colonies. The procedure specified in International Standard ISO 6785-1985 is similar but does not allow the options of using XLD or hectoen enteric agar.