TABLE 3.

Statistical comparison of heat-only and HPT inactivation at F_105°C for C. botulinum strains and C. sporogenes FRRB 2790 in agar and model products

Strain	Medium	Avg heat-only residual (log10 MPN/g)a	Avg HPT residual (log10 MPN/g)a	P value
FRRB 2802	MPA3679 agar	0.395 ± 0.137	−1.629 ± 0.356	4.95 × 10−6b
	30% (wt/wt) Bolognese sauce	0.122 ± 0.406	−1.203 ± 0.514	0.042c
	50% (wt/wt) cream sauce	−0.231 ± 0.346	−1.305 ± 0.507	0.050c
	Rice water agar	0.154 ± 0.306	−0.715 ± 0.292	0.069
FRRB 2803	30% (wt/wt) Bolognese sauce	0.066 ± 0.473	−0.874 ± 0.518	0.193
	50% (wt/wt) cream sauce	0.190 ± 0.444	−0.456 ± 0.577	0.340
	Rice water agar	0.083 ± 0.480	−0.656 ± 0.480	0.307
FRRB 2804	30% (wt/wt) Bolognese sauce	0.018 ± 0.278	−1.069 ± 0.336	0.017c
	50% (wt/wt) cream sauce	0.265 ± 0.305	−1.394 ± 0.843	0.003b
	Rice water agar	−0.034 ± 0.462	−1.262 ± 0.928	0.075
FRRB 2807	30% (wt/wt) Bolognese sauce	0.000 ± 0.223	−0.754 ± 0.480	0.047c
	50% (wt/wt) cream sauce	−0.296 ± 0.487	−0.925 ± 0.581	0.368
	Rice water agar	0.298 ± 0.606	−0.265 ± 0.622	0.533
FRRB 2806	30% (wt/wt) Bolognese sauce	0.121 ± 0.304	−0.455 ± 0.568	0.252
	50% (wt/wt) cream sauce	0.005 ± 0.198	−0.125 ± 0.434	0.682
	Rice water agar	0.001 ± 0.196	0.485 ± 0.502	0.147
FRRB 2790	30% (wt/wt) Bolognese sauce	−0.166 ± 0.367	−0.772 ± 0.501	0.288
	50% (wt/wt) cream sauce	−0.143 ± 0.268	−0.064 ± 0.415	0.840
	Rice water agar	0.000 ± 0.461	0.723 ± 0.542	0.302

^aData values are averaged residuals ± standard deviations; heat-only and HPT residuals were calculated for each sample as the difference between the actual inactivation and that predicted from a regression line fitted through the rep1 subset of the 105°C heat-only inactivation data.

^bP values of ≤0.01 indicate a highly statistically significant difference between the average residuals for the heat-only and HPT data at the 99% confidence interval.

^cP values of ≤0.05 indicate a statistically significant difference between the average residuals for the heat-only and HPT data at the 95% confidence interval.