Estimation of the enzyme levels of PPO and POD bananas using digital image processing and regression analysis during the storage period

Polyphenol oxidases )PPO( and peroxidases (POD) are enzymes that cause browning of fruits and vegetables, creating inappropriate appearance and reducing their quality. The purpose of this study was to evaluate the activity of bananas PPO and POD enzymes during storage at room temperature (25 °C). For this purpose, during the storage period on days 0, 3, 6 and 9, image processing, fractal and color parameters of the samples were extracted and then the samples were examined for enzyme activity. In this study, the fractal analysis to investigate the browning phenomenon of enzymes for banana; based on the image analysis, two fractal properties (FDavg and FDlac) and six color characteristics (r, g, b, L*, a*, b*) were investigated to develop the regression models. Finally, it was shown that FDavg and FDlac fractal properties could predict POD (R2 = 0.903) and PPO (R2 = 0.896) enzymes with higher accuracy than color properties. Finally, it was concluded that digital image processing along with multi-regression could effectively predict enzymes PPO and POD.