Table 2.
Recovery of E. coli O157:H7 from artificially-contaminated plant-based meat analogue (PBMA) samples through cultural enrichment.
| Sample ID | Presumptive E.coli O157:H7 abundance level after primary enrichment (x 108 CFU/ml) a,b,c |
||
|---|---|---|---|
| Control | Low | High | |
| A2 | 0 ± 0 | 11 ± 3 | 14 ± 2 |
| B1 | 0 ± 0 | 15 ± 4 | 16 ± 6 |
| C1 | 0 ± 0 | 9 ± 2 | 13 ± 2 |
| D1 | 0 ± 0 | 13 ± 1 | 19 ± 9 |
| E2 | NA | NA | NA |
| F1 | 0 ± 0 | 19 ± 6 | 20 ± 9 |
a
Samples were pre-inoculated with a model E.coli O157:H7 strain at the indicated levels. Control, no inoculation; Low, ∼14 CFU/25 g; High, ∼1200 CFU/25 g.
b
Numbers represent mean ± standard deviation values obtained from at least three independent determinations for each sample replicate and by spread-plating serial-dilutions of individual enrichment cultures onto Rainbow® Agar O157.
c
NA, not available. Sample E2 carried non-targeted Hafnia bacteria and resulted in false-positive results for both inoculation-free controls and inoculated samples.