3.4.1. Total Phenolic Content

The changes in TPC are shown in Figure 8. There were minimal changes in TPC as storage duration was extended, with no clear difference between fruit stored using low oxygen technologies and RA (Figure 8a). However, TPC reached a maximum of 40.64 ± 0.82 mg GAE/g DM for apples stored in RLOS + CA after 6 months. The lowest TPC (38.75 ± 0.06 mg GAE/g DM) was recorded after 8 months for RA stored fruit. In the 2016 season (Figure 8b), at 6 months, TPC appeared to significantly decrease for RA stored apples compared to low oxygen technologies. Following that, all low oxygen technologies, except DCA-CF, maintained TPC higher than RA treatment.

#### 3.4.2. Radical Scavenging Activity

In the 2015 season, significantly lower antioxidant activity in RA than in RLOS (ULO and CA) and DCA-CF sampled peels was recorded after 4, 8, and 10 months (Figure 9a). The RSA generally fluctuated during RLOS (ULO and CA) storage and DCA-CF treated peels, with no significant change. For RLOS (ULO and CA) and DCA-CF treated peels, there was no substantial difference in RSA between 0 and 7 d shelf life. As previously observed in the first harvest season (2015), RSA was stable for RLOS (ULO and CA) and DCA-CF treated peels in the 2016 season (Figure 9b). However, between 4 and 8 months of storage, a significant decrease in RSA was observed after 7 d shelf life for RA treated peels.

**Figure 8.** Total phenolic content (mgGAE/g DM) of 'Granny Smith' apples harvested in the 2015 (**a**) and 2016 (**b**) seasons at commercial maturity and stored for up to 10 months at 0 ◦C in various storage conditions, evaluated every two months followed by a 6 week simulated shipment and handling period, and at 7 days on the shelf (20 ◦C and 65% RH). Vertical bars represent the standard error (SE) of mean values of 3 replicates (1 replicate = 10 fruit). LSD0.05 represents least significant difference (*p* < 0.05). LSD0.05 represent least significant difference (*p* < 0.05). For storage duration, mon months; w—weeks; and d—days. RLOS—repeated low oxygen stress; ULO—ultra-low oxygen; CA—controlled atmosphere; DCA-CF—dynamic controlled atmosphere-chlorophyll fluorescence; RA—regular atmosphere.

**Figure 9.** Radical scavenging activity (mgGAE/g DM) of 'Granny Smith' apples harvested in the 2015 (**a**) and 2016 (**b**) seasons at commercial maturity and stored for up to 10 months at 0 ◦C in various storage conditions, evaluated every two months followed by a 6 week simulated shipment and handling period, and at 7 days on the shelf (20 ◦C and 65% RH). Vertical bars represents the standard error (SE) of mean values of 3 replicates (1 replicate = 10 fruit). LSD0.05 represent least significant difference (*p* < 0.05). For storage duration, mon—months; w—weeks; and d—days. RLOS—repeated low oxygen stress; ULO—ultra-low oxygen; CA—controlled atmosphere; DCA-CF—dynamic controlled atmosphere-chlorophyll fluorescence; RA—regular atmosphere.
