Soyabean Casein Digest Medium with 0.5% Soya Lecithin is used for sanitary examination of surfaces. Tryptone and Soyapeptone provide essential nutrients. Dextrose serves as source of fermentable carbohydrate for the energy production. Sodium chloride maintains osmotic balance while dipotassium phosphate provides buffering capacity. Lecithin is incorporated to neutralize any residual disinfectant activity.