Total Collaborative Study Protocol_Solus One Salmonella v1 1

powder matrix) and  Salmonella  Senftenberg ATCC 43845 (for whole black peppercorn matrix) inoculums 

were cultured by transferring a single colony from trypticase soy agar with 5% sheep blood (SBA) into 

BHI broth for 24 ± 2 h at 35 ± 2°C to obtain stationary phase cell densities. The  Salmonella  starter 

cultures were subsequently diluted in BHI broth, added to the respective matrices and subsequently 

mixed. At these low and high inoculum levels, fractional positives or consistently positive results at the 

time of sampling were anticipated. 

Three hundred and seventy five g of flavored ranch seasoning or honey onion mustard seasoning 

test portions were prepared by mixing together 25 g of inoculated test product with 350 g of un‐

inoculated test product respectively. 

The level of  Salmonella  in the low and high level inoculum for 25 g test portions were determined by 

Most Probable Number (MPN) on the day of analysis. Each test portion was enriched with the reference 

method enrichment (FDA/BAM Ch. 5) and analyzed by the reference method procedure. The number of 

positives from the 3 test levels were used to calculate the MPN value with 95% Confidence interval 

levels (8). 

For all matrices, a lyophilized culture was used. The lyophilized cultures were prepared by 

transferring a single  Salmonella  colony from SBA into BHI broth for 18–24 h at 35 ± 2°C. The cultures 

were then diluted in a sterile cryo‐protectant, reconstituted NFDM blend and freeze dried for 48–72 h. 

The lyophilized  Salmonella  cultures were subsequently diluted in powdered NFDM and used to inoculate 

a bulk lot of each respective matrix at levels that would yield fractional positives or consistently positive 

results at the time of sampling. Following inoculation, each bulk lot of the NFDM powder matrices were 

homogenized by hand and held for two weeks at room temperature (15–25°C) prior to analysis, thereby 

allowing time for the target organism to equilibrate within the respective samples. 

In addition, 225 mL and 3,375 mL Solus mBPW Medium supplemented with Solus One  Salmonella

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