Zook et al. (1999) in a study of inactivation of S. cerevisiae spores in three systems (apple and orange juices, and a model system) obtained the values of D in minutes presented in the following table. Determine the Zp values at the different pH levels. According to the Zp values, what is the effect of pH on spore baroresistance? Generate the spore population reduction curve (N/No vs time) at 385 MPa and pH of 3.5 until a reduction of 7 logarithmic cycles is reached.

D values in minutes

\begin{tabular}{|c|c|c|c|c|} \hline P(MPa) & pH=3.5 & pH=4.0 & pH=4.5 & pH=5.0 \\ \hline 500 & 0.14 & 0.19 & 0.18 & 0.19 \\ \hline 450 & 0.38 & 0.45 & 0.45 & 0.49 \\ \hline 400 & 0.72 & 0.93 & 0.86 & 0.98 \\ \hline 350 & 2.15 & 2.59 & 2.57 & 2.84 \\ \hline 300 & 7.21 & 10.05 & 10.02 & 9.42 \\ \hline \end{tabular} \begin{tabular}{|c|c|c|c|c|} \hline P(MPa) & pH=3.5 & pH=4.0 & pH=4.5 & pH=5.0 \\ \hline 500 & 0.14 & 0.19 & 0.18 & 0.19 \\ \hline 450 & 0.38 & 0.45 & 0.45 & 0.49 \\ \hline 400 & 0.72 & 0.93 & 0.86 & 0.98 \\ \hline 350 & 2.15 & 2.59 & 2.57 & 2.84 \\ \hline 300 & 7.21 & 10.05 & 10.02 & 9.42 \\ \hline \end{tabular}