Comparison of Primary Models to Predict Microbial Growth by the Plate Count and Absorbance Methods

Table 8

Growth parameters and their 95% confidence limits and coefficients of determination (), SSE, and RMSE of fit obtained with different growth models for average plate count growth curves of Listeria monocytogenes CECT 4031 at 37°C in TSB+YE inoculating 10², 10⁴, and 10⁶ CFU mL⁻¹ shown in Figure 3(b).

Growth model	Initial concentration (CFU mL^−1)	Lag time (h)	Growth rate; (log cycles h^−1)	(log CFU mL^−1)	(log cycles)			SSE	RMSE
Three-phase linear	10^2	2.00; (1.85–2.14)	0.487; (0.467–0.506)	1.988; (1.820–2.150)	—		0.997	0.0346	0.0620
	10^4	1.95; (1.75–2.06)	0.432; (0.424–0.441)	4.006; (3.970–4.040)	—		0.986	0.1525	0.1235
	10^6	2.00; (1.78–2.24)	0.423; (0.402–0.441)	6.113; (5.870–6.360)	2.554		0.985	0.0916	0.1070
Gompertz	10^2	2.13; (1.63–2.63)	0.542; (0.510–0.574)	1.803; (1.599–2.007)	6.071; (4.105–8.038)		0.997	0.0406	0.0672
	10^4	2.22; (1.63–2.81)	0.503; (0.443–0.564)	3.932; (3.755–4.109)	3.917; (2.982–4.852)		0.993	0.0691	0.0870
	10^6	2.27; (1.70–2.83)	0.485; (0.417–0.554)	6.009; (5.856–6.163)	3.227; (2.604–3.85)		0.992	0.0655	0.0853
Logistic	10^2	1.73; (0.75–2.71)	0.559; (0.511–0.606)	1.501; (1.086–1.917)	5.297; (3.521–7.073)		0.995	0.0614	0.0826
	10^4	1.91; (0.72–3.10)	0.513; (0.428–0.597)	3.715; (3.340–4.091)	3.739; (2.689–4.79)		0.989	0.1087	0.1099
	10^6	2.12; (1.18–3.06)	0.501; (0.415–0.587)	5.863; (5.599–6.127)	3.073; (2.465–3.681)		0.990	0.0841	0.0967
Richards	10^2	2.13; (1.41–2.85)	0.003; (−2.733–2.738)	1.803; (1.282–2.323)	6.068; (0.701–11.440)	0.002; (−1.865–1.868)	0.996	0.0407	0.0713
	10^4	2.22; (1.57–2.86)	0.0008; (−2.303–2.304)	3.932; (3.614–4.250)	3.917; (2.384–5.450)	0.0006; (−1.686–1.687)	0.992	0.0691	0.0929
	10^6	2.27; (1.70–2.84)	0.013; (0.011–0.015)	6.008; (5.854–6.163)	3.222; (2.601–3.843)	0.01^a	0.992	0.0657	0.0854
Baranyi	10^2	2.07; (1.84–2.31)	0.514; (0.494–0.534)	1.891	—		0.999		0.0453
	10^4	1.86; (1.34–2.37)	0.447; (0.410–0.483)	3.896	—		0.993		0.0875
	10^6	2.14; (1.64–2.64)	0.460; (0.402–0.517)	5.996	2.774		0.993		0.0774

Value fixed at bound.