Comparison between Hyperspectral Imaging and Chemical Analysis of Polyphenol Oxidase Activity on Fresh-Cut Apple Slices

Figure 5

Method comparison—Bland–Altman plot: (a) Bland–Altman plot: the differences between PPO predicted and PPO measured vs. the mean value of both measurements. Dashed grey lines indicate the limit of agreement (0 ± 1.96 SD of difference), the solid black line is the line of equality, the solid red line shows the mean difference (bias), and the dashed red lines show the 95% CI around the mean difference.