Nutrient broth is a general purpose medium used for the cultivation of a wide variety of fastidious and non-fastidious microorganisms with non-existent nutritional requirements. Peptone and yeast extract provide nitrogen compounds, vitamin B complex, amino acids and other nutrients essential for growth. Sodium chloride is used to maintain osmotic balance and glucose is the source of fermentable carbohydrates in the medium.

The nutrient broth is the same formulation as the nutrient agar, only the agar has been omitted. Nutrient broth is used as a pre-enrichment medium when testing certain foods and dairy products for Salmonella spp. In dried or processed foods, Salmonella can be sub-lethal and in low numbers. The presence of other bacteria and components of food samples can interfere with the growth and recovery of Salmonella spp. Pre-enrichment in a non-selective medium such as nutrient broth helps repair cell damage, dilutes toxic or inhibitory substances, and provides a nutritional advantage to Salmonella over other bacteria. Nutrient broth is included in many standard method procedures for testing foods, dairy products and other materials.