TABLE 2.
Goodness-of-fit measures and parameter values of the fitted models describing the survival of Salmonella Typhimurium in un-ionized ammonia solutions
| Treatment | Model | AICa,b | BICa,b | N 0 a , b | δ a , b | p a , b | α a , b | δ 1 a , b | δ 2 a , b | N res a , b |
|---|---|---|---|---|---|---|---|---|---|---|
| CHES, pH 9 | Weibull with tailing effects | −53.32 | −50.49 | 7.93 (7.78, 8.06) |
5.73 (4.82, 6.60) |
1.12 (0.97, 1.27) |
NA | NA | NA | 3.62 (3.31, 3.78) |
| 0.04 M NH3 | Double Weibull | −57.86 | −54.32 | 7.66 (7.53, 7.77) |
NA | 1.85 (1.70, 2.01) |
6.16 (5.79, 6.49) |
4.81 (4.42, 5.21) |
21.41 (18.10, 26.23) |
NA |
| 0.09 M NH3 | Weibull | −33.97 | −33.38 | 7.77 (7.67, 7.90) |
2.97 (2.74, 3.23) |
1.46 (1.39, 1.55) |
NA | NA | NA | NA |
| 0.18 M NH3 | Weibull | −52.95 | −52.36 | 7.73 (7.67, 7.77) |
0.42 (0.38, 0.45) |
0.61 (0.59, 0.62) |
NA | NA | NA | NA |
| 0.26 M NH3 | Weibull | −39.21 | −38.62 | 8.06 (7.93, 8.14) |
0.17 (0.13, 0.21) |
0.49 (0.46, 0.52) |
NA | NA | NA | NA |
a
Best-fit parameter values and their 95% confidence intervals (in parentheses) are reported.
b
AIC, Akaike information criterion; BIC, Bayesian information criterion; N0, initial inoculum concentration (log CFU/g); δ, time (h) to first decimal reduction; p, shape of inactivation curve; α, fraction of the first subpopulation remaining in the total population; δ1 and δ2, time (h) to first decimal reduction of first and second subpopulation, respectively; Nres, starting point of tail (log CFU/g); NA, not applicable.