## 3 Results
### Optical Properties of Red Pickly Pear Juice
\begin{table}
\begin{tabular}{l c c c c c c c c} \hline \hline \multicolumn{1}{c}{\multirow{2}{*}{**Treatment**}} & \multicolumn{6}{c}{\(\mathbf{pH3.6}\)} & \multicolumn{6}{c}{\(\mathbf{pH7}\)} \\ \cline{2-10}  & **Day 0** & **Day 5** & **Day 10** & **Day 20** & **Day 0** & **Day 5** & **Day 10** & **Day 20** \\ \hline Untreated juice (Control) & 54.5 \(\pm\) 0.2 \({}^{\mathrm{ad}}\) & 53.9 \(\pm\) 0.2 \({}^{\mathrm{b}}\) & 53.1 \(\pm\) 0.1 \({}^{\mathrm{cd}}\) & 52.8 \(\pm\) 1.0 \({}^{\mathrm{ad}}\) & 52.8 \(\pm\) 0.3 \({}^{\mathrm{*}}\) & 52.6 \(\pm\) 0.1 \({}^{\mathrm{b}}\) & 52.0 \(\pm\) 0.0 \({}^{\mathrm{ad}}\) & 52.0 \(\pm\) 0.2 \({}^{\mathrm{ad}}\) \\ UV-C (9.87)/cm\({}^{2}\) & 54.7 \(\pm\) 0.3 \({}^{\mathrm{cd}}\) & 55.2 \(\pm\) 0.1 \({}^{\mathrm{b}}\) & 54.6 \(\pm\) 0.2 \({}^{\mathrm{be}}\) & 54.4 \(\pm\) 0.1 \({}^{\mathrm{c}}\) & 52.9 \(\pm\) 0.2 \({}^{\mathrm{e}}\) & 54.4 \(\pm\) 0.1 \({}^{\mathrm{b}}\) & 55.2 \(\pm\) 0.1 \({}^{\mathrm{b}}\) & 59.3 \(\pm\) 0.0 \({}^{\mathrm{b}}\) \\ UV-C (15.13)/cm\({}^{2}\) & 54.8 \(\pm\) 0.3 \({}^{\mathrm{cd}}\) & 55.6 \(\pm\) 0.1 \({}^{\mathrm{b}}\) & 54.5 \(\pm\) 0.2 \({}^{\mathrm{c}}\) & 52.9 \(\pm\) 0.2 \({}^{\mathrm{e}}\) & 54.4 \(\pm\) 0.1 \({}^{\mathrm{b}}\) & 55.3 \(\pm\) 0.2 \({}^{\mathrm{b}}\) & 58.3 \(\pm\) 0.1 \({}^{\mathrm{b}}\) \\ UV-C (31.78)/cm\({}^{2}\) & 55.1 \(\pm\) 0.1 \({}^{\mathrm{bc}}\) & 55.7 \(\pm\) 0.7 \({}^{\mathrm{b}}\) & 55.1 \(\pm\) 0.2 \({}^{\mathrm{b}}\) & 54.8 \(\pm\) 0.1 \({}^{\mathrm{c}}\) & 53.3 \(\pm\) 0.1 \({}^{\mathrm{ad}}\) & 54.5 \(\pm\) 0.1 \({}^{\mathrm{b}}\) & 55.2 \(\pm\) 0.2 \({}^{\mathrm{b}}\) & 59.1 \(\pm\) 0.3 \({}^{\mathrm{b}}\) \\ HTST (80 \({}^{\mathrm{C}}\)) & 56.5 \(\pm\) 0.4 \({}^{\mathrm{b}}\) & 54.0 \(\pm\) 0.0 \({}^{\mathrm{b}}\) & 54.4 \(\pm\) 0.1 \({}^{\mathrm{bc}}\) & 55.0 \(\pm\) 0.4 \({}^{\mathrm{c}}\) & N/A & N/A & N/A & N/A \\ UHT (130 \({}^{\mathrm{C}}\)) & N/A & N/A & N/A & N/A & 68.6 \(\pm\) 0.1 \({}^{\mathrm{d}}\) & 63.86 \(\pm\) 6.4 \({}^{\mathrm{e}}\) & 64.2 \(\pm\) 1.3 \({}^{\mathrm{a}}\) & 64.4 \(\pm\) 0.4 \({}^{\mathrm{a}}\) \\ \hline \multicolumn{1}{c}{\multirow{2}{*}{**Treatment**}} & \multicolumn{6}{c}{\(\mathbf{pH3.6}\)} & \multicolumn{6}{c}{\(\mathbf{pH7}\)} \\ \cline{2-10}  & **Day 0** & **Day 5** & **Day 10** & **Day 20** & **Day 0** & **Day 5** & **Day 10** & **Day 20** \\ \hline Untreated juice (Control) & 64.0 \(\pm\) 0.1 \({}^{\mathrm{a}}\) & 63.5 \(\pm\) 0.5 \({}^{\mathrm{a}}\) & 63.5 \(\pm\) 0.0 \({}^{\mathrm{a}}\) & 63.3 \(\pm\) 0.1 \({}^{\mathrm{a}}\) & 63.7 \(\pm\) 0.2 \({}^{\mathrm{ab}}\) & 63.6 \(\pm\) 0.1 \({}^{\mathrm{a}}\) & 62.5 \(\pm\) 0.1 \({}^{\mathrm{a}}\) & 62.1 \({}^{\mathrm{a}}\) & 62.1 \({}^{\mathrm{a}}\) \\ UV-C (9.87)/cm\({}^{2}\) & 62.0 \(\pm\) 0.4 \({}^{\mathrm{ac}}\) & 61.9 \(\pm\) 0.0 \({}^{\mathrm{a}}\) & 63.4 \(\pm\) 0.2 \({}^{\mathrm{a}}\) & 63.2 \(\pm\) 0.1 \({}^{\mathrm{a}}\) & 60.1 \(\pm\) 0.2 \({}^{\mathrm{c}}\) & 58.3 \(\pm\) 0.2 \({}^{\mathrm{ac}}\) & 56.8 \(\pm\) 0.3 \({}^{\mathrm{b}}\) & 47.4 \(\pm\) 0.8 \({}^{\mathrm{d}}\) \\ UV-C (15.13)/cm\({}^{2}\) & 61.3 \(\pm\) 0.3 \({}^{\mathrm{b}}\) & 61.9 \(\pm\) 0.2 \({}^{\mathrm{a}}\) & 63.0 \(\pm\) 0.1 \({}^{\mathrm{a}}\) & 62.8 \(\pm\) 0.4 \({}^{\mathrm{a}}\) & 60.2 \(\pm\) 0.1 \({}^{\mathrm{c}}\) & 58.3 \(\pm\) 0.1 \({}^{\mathrm{b}}\) & 56.5 \(\pm\) 0.0 \({}^{\mathrm{b}}\) & 50.1 \({}^{\mathrm{a}}\) \\ UV-C (31.78)/cm\({}^{2}\) & 61.2 \(\pm\) 0.1 \({}^{\mathrm{b}}\) & 61.0 \(\pm\) 0.2 \({}^{\mathrm{ab}}\) & 62.2 \(\pm\) 0.0 \({}^{\mathrm{a}}\) & 62.4 \(\pm\) 0.0 \({}^{\mathrm{ab}}\) & 59.7 \(\pm\) 0.3 \({}^{\mathrm{c}}\) & 57.5 \(\pm\) 0.0 \({}^{\mathrm{c}}\) & 56.8 \(\pm\) 0.1 \({}^{\mathrm{b}}\) & 48.7 \(\pm\) 0.0 \({}^{\mathrm{ad}}\) \\ HTST (80 \({}^{\mathrm{C}}\)) & 59.8 \(\pm\) 0.5 \({}^{\mathrm{c}}\) & 62.6 \(\pm\) 0.2 \({}^{\mathrm{a}}\) & 62.3 \(\pm\) 0.2 \({}^{\mathrm{a}}\) & 60.9 \(\pm\) 0.1 \({}^{\mathrm{b}}\) & N/A & N/A & N/A & N/A \\ UHT (130 \({}^{\mathrm{C}}\)) & N/A & N/A & N/A & N/A & 32.8 \(\pm\) 1.8 \({}^{\mathrm{d}}\) & 31.4 \(\pm\) 2.2 \({}^{\mathrm{d}}\) & 39.5 \(\pm\) 1.3 \({}^{\mathrm{c}}\) & 38.4 \(\pm\) 0.8 \({}^{\mathrm{a}}\) \\ \hline \mulOther color parameters, _chroma*_ and _lue angle_ represent the saturation and purity of the color, respectively.