Quality and volatile emission changes of "mondial gala" apples during on-tree maturation and postharvest storage in air or controlled atmosphere

Starch index (SI), color, firmness, titratable acidity (TA), soluble solids content (SSC), ethylene production, and aroma volatile emission were recorded weekly during on-tree maturation of `Mondial Gala' apples. Fruit were harvested on commercial date and held for 3.5 and 6.5 months in regular atmosphere (RA) or in three controlled atmospheres (CA) (2% O2 :2% CO2, 1% O2 : 1 % CO2 and 1% O2 :3% CO2). After each storage period plus 0 and 7 days at 20 °C, color, firmness, TA, SSC, aroma volatile emission, acetaldehyde and ethanol concentrations, and sensory acceptability were evaluated. At orchard, changes in SI, SSC, background color, and aroma volatile emission were almost concomitant or slightly previous to the increase in ethylene production. During storage, all three CA conditions, regardless of storage period, led to better preservation of standard quality. CA-stored fruit also received higher acceptability scores, although aroma volatile emission was decreased in response to these storage conditions....