ERP Micro December 2019

Frozen Finely Textured Beef – 375 g Test Portion (Unpaired) Method Comparison

Of the 20 low inoculation level replicates of the Assurance® GDS for E . coli O157:H7 Tq assay, by manual (hand) processing, there were 10 presumptive positives and 9 confirmed positives following the traditional confirmation procedures. There were 0 (zero) confirmed positives for the reference method. Of the 5 high inoculation level replicates, there were 5 presumptive positives and 5 confirmed positives following the traditional confirmation procedures. There were 2 confirmed positives for the reference method. The POD analysis between the GDS EHEC presumptive (POD CP ) and confirmed results (POD CC ) indicated that there was no statistically significant difference at the 5% level for both at the 10 h of enrichment (14). MPN analysis of the inoculation levels determined the concentration of E . coli O157:H7 for the low level was 0.00 MPN/test potion and 0.46 MPN/test potion for the high level. All uninoculated samples were negative. The POD analysis between the GDS EHEC methods presumptive (POD C ) and reference method confirmed (POD R ) results indicated that there was a statistically significant difference at the 5% level for both methods. The recovery of E . coli O157:H7 was much higher after enrichment in mEHEC broth (candidate method) compared to mTSB (reference method). As a result, the dPOD values were considered statistically significant. Carcass Cloths (Unpaired) Method Comparison Of the 20 low inoculation level replicates of the Assurance® GDS for E . coli O157:H7 Tq assay, by manual processing, there were 10 presumptive positives and 10 confirmed positives following the traditional confirmation procedures. There were 2 confirmed positives for the reference method. Of the 5 high inoculation level replicates, there were 3 presumptive positives and 3 confirmed positives following the traditional confirmation procedures. There was 1 confirmed positive for the reference method. The POD analysis between the GDS EHEC presumptive (POD CP ) and confirmed results (POD CC ) indicated that there was no statistically significant difference at the 5% level for both at the 8 h of enrichment. All uninoculated samples were negative. The POD analysis between the GDS EHEC methods presumptive (POD C ) and reference method confirmed (POD R ) results indicated that there was a statistically significant difference at the 5% level for both methods. The recovery of E . coli O157:H7 was much higher after enrichment in mEHEC broth (candidate method) compared to mTSB (reference method). As a result, the dPOD values were considered statistically significant.