Application of Dynamic Controlled Atmosphere Technologies to Reduce Incidence of Physiological Disorders and Maintain Quality of 'Granny Smith' Apples

The efficacy of dynamic controlled atmosphere technologies; repeated low oxygen stress (RLOS) and dynamic controlled atmosphere-chlorophyll fluorescence (DCA-CF) to control superficial scald development on 'Granny Smith' apples during long-term storage was studied. Fruit were stored for 2, 4, 6, 8, and 10 months at 0 degrees C in DCA-CF (0.6% O-2 and 0.8% CO2), regular atmosphere (RA)(approximate to 21% O-2 and 90-95% RH), and RLOS treatments: (1) 0.5% O-2 for 10 d followed by ultra-low oxygen (ULO) (0.9% O-2 and 0.8% CO2) for 21 d and 0.5% O-2 for 7 d or (2) 0.5% O-2 for 10 d followed by controlled atmosphere (CA) (1.5% O-2 and 1% CO2) for 21 d and 0.5% O-2 for 7 d. Development of superficial scald was inhibited for up to 10 months and 7 d shelf life (20 degrees C) under RLOS + ULO and DCA-CF treatments. Apples stored in RLOS + ULO, RLOS + CA, and DCA-CF had significantly (p < 0.05) higher flesh firmness and total soluble solids. The RLOS phases applied with CA or ULO and DCA-CF storage reduced the development of superficial scald by possibly suppressing the oxidation of volatiles implicated in superficial scald development.

Automated summary

The study found that using repeated low oxygen stress and dynamic controlled atmosphere technologies can effectively inhibit superficial scald development on apples during long-term storage, while also maintaining higher flesh firmness and total soluble solids in the fruit. The combination of RLOS phases with controlled atmosphere or ultra-low oxygen storage, as well as DCA-CF treatment, reduced the development of superficial scald possibly by suppressing the oxidation of volatiles related to scald development.