3. For each portion of the sample 1 ml of suspension/solution shall be transferred to a sterile 90 mm petri dish (in duplicate), to which 15 ml of egg yolk-free tryptose sulphite cycloserine agar (EY-free TSC agar)(1) at a temperature of 46°C ± 1°C shall be added and immediately gently mixed by swirling the dish with 5 clockwise and 5 anticlockwise circular movements.
EY- free TSC agar. See Hauschild, A.H.W. and Hilsheimer, R. (1974) Applied Microbiology 27:78–82. American Society for Microbiology, 1913 1 St N.W., Washington DC 20006, USA