Description
TSI Agar is a differential medium for identifying Enterobacteriaceae from pure cultures.
Glucose, lactose and sucrose fermentation changes phenol red from red to yellow and may produce gas, while thiosulfate and ferrous ions reveal hydrogen-sulfide production through blackening.
A pure colony is stab-inoculated into the butt and streaked over the slant. Tubes are incubated aerobically at 35 ± 2°C for 18–24 hours before slant, butt, gas and blackening reactions are interpreted.
