|Yeast extract||10 g|
|Phenol red (1% solution in 95% ethanol)||5.0 ml|
|Distilled water||1 liter|
Heat to dissolve tryptose, yeast extract, and lactose in 400 ml water. Suspend gelatin in 600 ml water and heat at 50-60°C with agitation to dissolve. Mix 2 solutions. Adjust pH to 7.5 ± 0.2. Add phenol red and mix. Dispense 10 ml portions into 16 × 150 mm screw-cap tubes. Autoclave 10 min at 121°C. If not used within 8 h, deaerate by heating at 50-70°C for 2-3 h before use.
Original Source: Bacteriological Analytical Manual, 8th Edition, Revision A, 1998.