*3.5. Changes in Total Phenolic and Lignin Contents*

In general, there was an increasing tendency in the content of total phenolic as the storage period prolonged in all the treatments (Figure 2a and Table S5). The application of preharvest chitosan at both concentrations caused the greatest content of total phenolic at harvest and this trend continued during the cold storage. Although 100 mg·L−<sup>1</sup> chitosantreated fruit maintained higher total phenolic content during the cold storage it was not statistically significant with untreated fruit at 30 and 60 days of storage. However, at the end of the storage period, the untreated fruit had the lowest total phenolic content (106.4 mg/100 g), while chitosan-treated fruit had total phenolic content of 121.3 and 124.2 mg/100 g for 100 and 500 mg·L−<sup>1</sup> applications, respectively.

As shown in Figure 2b, the total lignin content increased over the whole storage in all the treatments (Table S5). There were no differences in total lignin content at harvest; however, the changes (*p* ≤ 0.05) in the content of total lignin between treatments became apparent from 30 days of storage. The application of preharvest chitosan at 500 mg·L−<sup>1</sup> was associated with the greatest (*p* ≤ 0.05) total lignin content throughout the storage time, and this was followed by the 100 mg·L−<sup>1</sup> chitosan-treated fruit.

**Table 3.** Effects of preharvest chitosan application on soluble solids content, titratable acidity, total sugar content (HPLC analysis), total acid content (HPLC analysis), and their ratios in 'Garmrok' kiwifruit during cold storage. Experimental data represent means ± standard error with n = 10 (SSC) and n = 3 (titratable acidity, total sugar content, total acid content, and their ratios). \*, in each column indicate significant differences between treatments at each sampling date, according to the least significant difference (LSD) test at *p* ≤ 0.05.

