Abstract
Apples (Malus × domestica Borkh.) are stored up to one year, however, postharvest technologies designed to preserve texture, taste and to extend storage life may alter aroma by affecting volatile organic compound (VOC) biosynthesis. This study investigated VOC dynamics in two commercially important cultivars with contrasting ripening physiology, ‘Red Delicious’ and ‘Granny Smith’. VOC profiles were characterized during field ripening to establish cultivar-specific references. Subsequently, the effects of storage atmospheres (regular air, RA; ultra-low oxygen, ULO; and dynamic controlled atmosphere based on chlorophyll fluorescence, DCA-CF), with or without 1-methylcyclopropene (1-MCP), and an additional 8-week shelf-life period in RA were evaluated. During field ripening, ‘Red Delicious’ showed a climacteric pattern, shifting from aldehyde- to ester-dominated profiles, whereas ‘Granny Smith’ maintained low ethylene production and an aldehyde-driven profile. Across storage treatments, 1-MCP had the strongest effect, markedly suppressing VOC production, particularly esters in ‘Red Delicious’ and alcohols in ‘Granny Smith’, especially under DCA-CF. RA promoted higher VOC accumulation, while ULO and DCA-CF limited VOC production. Post-storage recovery partially restored alcohols and ester biosynthesis in ‘Red Delicious’, with negligible effects in ‘Granny Smith’. Multivariate analysis indicated that RA + 1-MCP, ULO and DCA-CF preserved aroma similarity to field reference in ‘Red Delicious’, whereas only ULO and DCA-CF, when combined with 1-MCP, preserved aroma similarity in ‘Granny Smith’. VOC discrimination was driven by esters in ‘Red Delicious’ and by aldehydes and alcohols in ‘Granny Smith’. These results highlight cultivar-specific trade-offs between storage conditions and aroma, supporting the use of field-reference VOC profiles as benchmarks for optimizing postharvest strategies.