TABLE 2.
Effect of pH on inactivation of E. coli in fermented meats and analogous aqueous systems from linear regression analyses of inactivation versus pH variables
| y axis | x axis | No. of data points | Linear regression equation | R2 |
|---|---|---|---|---|
| Total inactivation (log10 CFU/unit) | Final pH | 360 | y = −0.8647x + 5.9447 | 0.0698 |
| Reduction in pHa | 163 | y = 1.6092x − 0.0217 | 0.0965 | |
| Rate of reduction in pHa,b | 163 | y = 27.8847x + 0.8466 | 0.2343 | |
| Log10-transformed inactivation rate (log10 CFU/unit/h) | Final pH | 360 | y = −0.3123x − 0.3410 | 0.0265 |
| Reduction in pHa | 149 | y = 0.3346x − 2.0538 | 0.0374 | |
| Rate of reduction in pHa,b | 149 | y = 14.7078x − 2.1350 | 0.5851 | |
| Temperature residualsc | Final pH | 352 | y = 0.2306x − 1.0065 | 0.0127 |
| Reduction in pHa | 149 | y = −0.6221x − 0.8302 | 0.0483 | |
| Rate of reduction in pHa,b | 149 | y = −16.2437x − 1.0065 | 0.2663 |
a
During fermentation.
b
pH units/h.
c
Data were normalized for the effect of temperature by using the Arrhenius model: ln[inactivation rate (log10 CFU/unit/h)] = 30.974 − 10,483 × [1/absolute temperature (K)] (equation 2).