# Quality Assessment of Banana Ripening Stages by Combining Analytical Methods and Image Analysis
## 3 Results and Discussion
### Physicochemical Parameters of the Banana Flesh during Storage
Although many studies have referred to the changes in the color of the banana peel during ripening, there were no competent reports on the corresponding changes in the banana flesh. Therefore, the color changes of the banana flesh could be attributed to the moisture content increasing and the oxygen penetration of the flesh during the storage period. Moreover, the redness (a*) fluctuations of the banana flesh could be associated with the total carotenoid-content differentiation during ripening [34]. The texture attributes, such as firmness, springiness, adhesiveness, cohesiveness, and chewiness, of the banana flesh at days 2, 4, 7, 9, 11, 14, 17, and 21 are shown in Figure 7. The firmness of the banana flesh presented a dramatic (\(p<0.05\)) decrease at day 4, and then it gradually (\(p<0.05\)) decreased until day 21. These results were in accordance with other  
Figure 6: Lightness (L*), redness/greenness (a*), yellowness/blueness (b*), and hue angle (h) of the banana-flesh samples during storage at 18.0 \(\pm\) 0.5 \({}^{\circ}\)C.  
research that had also mentioned the contributions of starch hydrolysis, the enzymatic disruption of the cell wall structure, and the water migration from the banana peel to the pulp, to banana flesh softening [14; 35]. Moreover, [PERSON] et al. [36] pinpointed a 50% firmness reduction in bananas, which occurred during 3 days of ripening. Springiness (including the ratio of the distance of the height, during the second compression, to the original compression distance), which was related to flesh elasticity, exhibited a slight (\(p>0.05\)) decrease. Adhesiveness, which was the force required to overcome the contact between the surfaces of the product and the probe, showed a dramatic (\(p<0.05\)) decrease at day 7 and, afterwards, gradually (\(p<0.05\)) decreased until day 21. Cohesiveness, which corresponded to the ratio of the tensile strength measurements during the first and second compressions of the area, showed a significant decrease at day 7, a fluctuation up to day 11, and afterwards, a stabilization until the final day of storage. Chewiness, which was calculated as firmness \(\times\) cohesiveness \(\times\) springiness and expressed the energy required to chew solid food, showed a significant (\(p<0.05\)) decrease at day 7 of the experiment, and then, it stabilized until the end of storage period. Interestingly, the variations of most texture attributes among the daily banana samples were minimized as the storage time increased. This agreed with previous reports in the literature, as other researchers had found that the texture attributes of the banana flesh decreased dramatically as ripening progressed [12; 37]. Therefore, texture is an important parameter that changes during banana ripening. Pairwise Correlation Matrix of Pairs of Physicochemical Parameters of the Banana Flesh and the Features \(L^{*}\), \(a^{*}\), \(b^{*}\) of the Banana Peel, during Storage  
To deepen our research, we created a pairwise correlation matrix (Figure 8) to showcase the pairwise correlations of the physicochemical parameters of the banana flesh and the features L\({}^{*}\), a\({}^{*}\), b\({}^{*}\) of the banana peel, during storage. The most substantial finding was related to the correlations (\(p<0.05\)) between the a* parameter of the banana peel and the moisture content, the TSS (Brix), the firmness, and the adhesiveness of the banana flesh (high positive 0.81, strong positive 0.72, high negative \(-0.89\), and strong negative \(-0.74\), respectively), as well as in the a*--b* and a*--L* parameters of the banana peel (high negative \(-1\), and strong negative \(-0.77\), respectively). The negative correlation of the a* and b* parameter of the banana peel could have been a result of the degradation of the chlorophyll with the parallel increase in the carotenoid and anthocyanin contents [38].