that are based on the protein hydrolysates of casein or peptone that allow for the recovery of stressed and injured cells that might be present in contaminated foods [11; 12; 14]. Buffered Peptone Water (BPW) is recommended in the methods published by the USDA's Food Safety and Inspection Service (USDA-FSIS) and the International Organization for Standardization (ISO) to pre-enrich _Salmonella_ from chicken and other foods [11; 12; 13]. Trypic Soy Broth (TSB) is a common peptide-based, laboratory growth medium that is routinely used for _Salmonella_ growth and is also used in non-selective enrichment of _Salmonella_ from eggs and spices according to the Food and Drug Administration (FDA) method [11]. Culture bias in laboratory media influences the serovars of _Salmonella_ that arise from samples containing multiple subtypes [7; 15; 16]. The _Salmonella_ serovar Kentucky is prevalent in poultry in the U.S. and is frequently isolated in _Salmonella_ enrichments, where it outgrows strains of serovars such as Typhimurium and Enteritidis [7; 17; 18]. Similarly, \(S\). Give is frequently isolated from surface water and from ruminants [9; 19; 20; 21; 22]. The bias can be problematic when conducting food surveillance or outbreak tracebacks because the serovars Kentucky and Give are rarely associated with human illness in the U.S. [4]. In the U.S., \(S\). Kentucky and \(S\). Give are more fit in commonly used _Salmonella_ enrichment protocols and can outgrow and mask the presence of strains of \(S\). Typhimurium and \(S\). Enteritidis [7; 15; 22; 23]. In Europe, the Middle East, and several African countries, an antibiotic-resistant \(S\). Kentucky Sequence Type 198 has arisen to cause multiple cases of human illness. While ST198 has caused human illness in the U.S., the number of cases is markedly lower [24; 25]. In BPW and TSB, peptides serve as the sources of carbon, nitrogen, sulfur, phosphorus, and energy for the microbiota. Differences between strains in the utilization of media components may affect the final recovery of strains in the mixture. These differences may be intensified when nutrients affect many roles in cellular metabolism. For example, proteomic analysis of the \(S\). Typhimurium strain 14028s revealed over 300 proteins that are regulated by phosphorus-limiting conditions [26]. Phosphorus metabolism via the uptake of inorganic phosphate (Pi) has effects on magnesium and calcium homeostasis [27; 28]. In _Salmonella_, phosphate homeostasis is controlled by protein synthesis by responding to reductions in ATP, destabilized ribosomes, or low cytoplasmic magnesium [29]. Phosphate levels are sensed and controlled through the actions of PhoB/PhoR, a two-component regulatory system in which PhoR is an integral membrane-bound sensor histidine kinase, which autophosphorylates when Pi levels are low, and transfers that phosphoryl group to PhoB. PhoB is a transcriptional regulator responsible for the moderation of gene expression of Pho genes. One of the operons affected by PhoB is the _pstSCAB_ operon, which encodes a high-affinity ABC-type transporter responsible for the transport of Pi into the cell [30; 31; 32]. When intracellular Pi concentrations are high, the transporter is turned off through the interaction of the PhoU protein with the PstB component of the transporter. This PhoU-PstB interaction is mediated through the action of the sensor kinase PhoR [29; 31]. Also, during periods of low Pi, the Pho regulon plays a role in maintaining the stability of the stationary phase and stress response sigma factor RpoS through the actions of the small protein IraP. IraP assures the continued action of RpoS by binding to and inhibiting the RssB adaptor protein so that RssB is unable to bind to RpoS and target it for degradation [30; 32; 33]. In addition to phosphate metabolism, low nutrient conditions induce ppGpp, which slows protein synthesis and may induce a stress response [34].