XLT 4 Agar is a selective and differential culture medium designed for the isolation of Salmonella species, particularly from food products and environmental samples. The formulation contains xylose, lysine, and tergitol 4, which suppress competing microorganisms while supporting the growth of Salmonella. Characteristic colony color changes and hydrogen sulfide production assist in the identification of target organisms during microbiological analysis. Each plate contains approximately 20mL of prepared medium dispensed in a standard 100x15mm petri dish. XLT 4 Agar is commonly used in food safety laboratories, environmental monitoring programs, and microbiology research facilities where reliable detection of Salmonella contamination is required.