## 3 Results
### Impact of Plant-Based Coatings on \"Rocha\" Pear Physiology during Storage
#### 3.3.2 Accumulation of Conjugated Trienols (CTs)  
The evolution of the CTs content in the pear peel was monitored throughout the storage assay and the results obtained for the NA and DCA storage conditions are shown in Figure 6a,b, respectively.  
Figure 5: Evolution of the hue angle (h\({}^{\circ}\)) of “Rocha” pear at 9, 32, 73, 101, and 134 days. (**a**) NA (normal atmosphere); (**b**) DCA (dynamic controlled atmosphere) storage conditions. For each type of storage, four coating conditions are presented as follows: CTR (control), PCT (pectin), CT1 (coating 1), and CT2 (coating 2). Values are mean \(\pm\) SD of ten replicates. The values followed by the same lowercase letter indicate no significant differences at the same sampling time between storage conditions, and by the same uppercase letter indicate no significant differences between sampling times within each coating condition (LSD test at \(p<0.05\)).  
These compounds, resulting from the in vivo oxidation of \(\alpha\)-farresene, are generally associated with the appearance of SC in pears, although critical values responsible for causing SC were never defined [47]. As such, and according to other studies, it is expected that their content would increase over storage [5]. As seen in Figure 6, such a trend is observed in both storage conditions, although the maximum CTs content reached in the two atmospheres are considerably different. In NA, the maximum value of CTs verified was \(9.27\pm 1.57\) nmol/cm\({}^{2}\) (\(t=101\) days) in the samples treated with the CT2, whereas, in the DCA, the maximum is reached also at the end of 101 days and, in the CTR condition (\(1.17\pm 0.37\) nmol/cm\({}^{2}\)). This difference is in line with what would be expected given the positive effect of the DCA storage conditions already reported in the literature concerning the prevention of the oxidation of \(\alpha\)-farresene into CTs [8].  
Figure 6: Evolution of conjugated trinols (CTs) content in the peel of “Rocha” pear. (**a**) NA (normal atmosphere); (**b**) DCA (dynamic controlled atmosphere) storage conditions. For each atmospheric storage, four coating conditions are presented as follows: CTR (control), PCT (pectin), CT1 (coating 1), and CT2 (coating 2). Values are mean \(\pm\) SD of five replicates. The values followed by the same lowercase letter indicate no significant differences at the same sampling time between storage conditions, and by the same uppercase letter indicate no significant differences between sampling times within each coating condition (LSD test at \(p<0.05\)).  
Within NA conditions (Figure 6a), it is possible to observe that the CTR, PCT, and CT2 conditions behave similarly with an increase of CTs up to 101 days and a subsequent decrease in the last sampling point. CT1 shows a less accentuated growth until day 73, suggesting a delay in the synthesis of CTs in the pear skin and this treatment has a potential positive effect at preventing SC appearance in NA storage conditions. In DCA storage (Figure 6b), the coated conditions have a similar behavior between them but differ from the CTR by presenting a lower CTs content from day 32 until the end of the assay. This observation indicates a positive effect of the presence of the coating on CTs content when stored at DCA.