Tryptic soy agar (TSA) + VRG
The image shows a combined TSA and VRG agar plate. On plate A, no bacteria have been streaked out, while Escherichia coli has been streaked out on plate B. - Click on the image to enlarge it.
"Tryptic soy agar (TSA)" is a general medium, which is used for isolation and enumeration of many different bacteria, among others, E. coli.
The medium contains:
The final pH of the medium should be 7.3.
TSA is often used in combination with VRG agar. TSA is then mixed with the sample to be analyzed at around 40°C and poured into the plates. After preincubation for 1-2 h at ambient temperature, the TSA is overlayed with VRB agar and the incubation is then continued at 37°C.