|GALENI, MARCELLA - WASHINGTON STATE UNIVERSITY|
|TORRES, CAROLINA - WASHINGTON STATE UNIVERSITY|
Submitted to: American Society of Horticulture Science Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 5/5/2021
Publication Date: N/A
Technical Abstract: Dynamic controlled atmosphere (DCA) storage can be used as an alternative to store organic apples for extended periods of time. This storage system uses low oxygen (O2) levels and monitors the anaerobic compensation point (ACP). ‘Honeycrisp’ apples from 4 different orchard locations were picked at commercial harvest maturity and placed into controlled atmosphere (CA) storage regimes. Initial ACP was monitored using chlorophyll fluorescence (CF), respiratory quotient (RQ), and ethanol content. Final CA conditions were: CA-CF (3kPa O2/0.5 kPa CO2), CA-RQ (3kPa O2/0.5 kPa CO2), and Initial low oxygen stress (ILOS); 0.5kPa O2/0.5kPa CO2 -10 days, 1.0kPa O2/0.7MPa CO2 thereafter). All treatments included 7 days of preconditioning at 50°F in air. Fruit quality (fruit weight, flesh firmness, soluble solids concentration (SSC), titratable acidity (TA), internal ethylene concentration, and respiration rate) and physiological disorders incidence were assessed after 6 and 9 months of storage plus 4 weeks in air. Storage conditions had no impact on flesh firmness, SSC, weight, or TA after 6 and 9 months. However, the respiration rate was only significantly higher after 9 months in CA-CF compared to rest of the treatments. Nevertheless, there were significant differences in firmness, SSC, TA, and respiration rate between orchards locations. The development of soft scald (SS) and soggy breakdown (SB) were significantly different among storage conditions, but no significant bitter pit (BP) differences were found after 6 months of storage. Fruit in CA-CF had 11.3% and 6% of SS and SB, respectively, while ILOS also had 11.3% of SS, but no SB incidence. CA-RQ had 4.3% and 1% of SS and SB, respectively. Whereas no significant differences were found amongst storage conditions after 9 months of storage. In contrast, orchard locations had a significant effect on SS, SB, and BP.