TABLE 3.
Reductions in numbers of viable Salmonella Typhimurium cells on ham slice surfaces treated with UV, NIR, and NIR-UV
| Treatment time (s) | Log reduction (log10
n0 − log10
n) by treatment type and selective mediuma |
|||
|---|---|---|---|---|
| UV (XLD) | NIR (XLD) | NIR-UV |
||
| XLD | OV-XLD | |||
| 0 | 0.00 ± 0.00A | 0.00 ± 0.00A | 0.00 ± 0.00Aa | 0.00 ± 0.00Aa |
| 10 | 1.16 ± 0.17B | 0.03 ± 0.03A | 1.55 ± 0.23Ba | 1.38 ± 0.16Ba |
| 20 | 1.22 ± 0.16B | 0.06 ± 0.00A | 1.68 ± 0.37Ba | 1.46 ± 0.19Ba |
| 30 | 1.48 ± 0.22C | 0.06 ± 0.04A | 1.71 ± 0.34Ba | 1.55 ± 0.23Ba |
| 40 | 1.56 ± 0.14C | 0.11 ± 0.12A | 1.96 ± 0.35BCa | 1.83 ± 0.39BCa |
| 50 | 1.57 ± 0.15C | 0.43 ± 0.30B | 2.31 ± 0.30Ca | 2.25 ± 0.24Ca |
| 60 | 1.63 ± 0.12C | 1.19 ± 0.20C | 3.05 ± 0.32Da | 2.78 ± 0.27Da |
| 70b | 1.73 ± 0.03C | 1.68 ± 0.03D | 4.17 ± 0.11Ea | 3.66 ± 0.34Ea |
a
The values are means ± standard deviations from three replications. Means with the same uppercase letter in the same column are not significantly different (P > 0.05). Within the NIR-UV columns, values in the same row followed by the same lowercase letter are not significantly different (P > 0.05). XLD, xylose lysine desoxycholate agar; OV-XLD, overlay XLD on TSA; n0, initial population; n, population after treatment.
b
A statistically significant (P < 0.05) difference between the sum of NIR and UV inactivation and inactivation achieved with combination treatment was observed.