Buffered Peptone Water (ISO) is used for pre-enriching damaged Salmonellaspp. from various food sources. As Salmonella may be present in low numbers and/or sub-lethally injured, pre-enrichment provides the cells with time to repair and multiply before being introduced to selective culture, thereby improving the chances of recovery from the sample. Enzymatic Digest of Casein is the nitrogenous source for bacterial growth. Mono- and Disodium Phosphate act as pH buffers. Sodium Chloride maintains the osmotic equilibrium.