TABLE 4.
PCR detection of and toxin production by C. botulinum type E in vacuum-packaged hot-smoked rainbow trout fillets and whole whitefish stored at 8°C for 1 to 5 weeks
| Fish species | Process | PCR detection and toxin production by C. botulinum type Ea at:
|
||
|---|---|---|---|---|
| 1 wk | 3 wk | 5 wk | ||
| Rainbow trout | RI | 4/4 (2.0) | 3/4 (2.4) | 2/4 (1.4) |
| RII | 2/4 (2.0) | 1/4 (1.4) | 1/4 (1.1) | |
| RIII | 0/4 (<0.8) | 0/4 (<0.8) | 1/4 (1.1) | |
| RIV | 0/4 (<0.8) | 0/4 (<0.8) | 0/4 (<0.8) | |
| Whitefish | WI | 3/4 (2.6) | 4/4 (3.8) | 3/4 (3.2), T |
| WII | 0/4 (<0.8) | 0/4 (<0.8) | 0/4 (<0.8) | |
| WIII | 2/4 (1.6) | 4/4 (4.3) | 4/4 (3.0), T | |
| WIV | 0/4 (<0.8) | 0/4 (<0.8) | 0/4 (<0.8) | |
a
Number of positive samples/number of all samples tested (the MPN estimate [log10 CFU/kilogram] for the C. botulinum type E count is given in parentheses). T, botulinum toxin was detected in three (process WI) or two (process WIII) samples. All others were negative for type E toxin.