S23 - Session O2 - Effect of RQ-based dynamic controlled atmosphere on some quality attributes and volatile aroma metabolites (VAMs) of `Jonagold´ apples

Authors: Karimi Solomon *, Maarten Hertog, Bart Nicolai

Jonagold apples are typically stored under controlled atmosphere (1.0 kPa O 2 and 2.5 kPa CO 2 at 1 °C) for eight months. Even so, significant quality losses occur after long-term storage which include; high incidence of physiological disorders, loss of flesh firmness and a significant decrease in volatile metabolites production and emission. The recommended oxygen concentration allows a safe margin above the anaerobic compensation point (ACP)nthe O 2 concentration at which CO 2 production is minimal. However, this is not always the case as ACP may vary with origin, season and picking date, leading to a suboptimal oxygen concentration being used. By monitoring the respiratory quotient (RQ) the moment a specific batch of fruit reaches a critical level of fermentation, which might lead to production of off-flavors, can be identified. Therefore, the more recent approach of dynamic controlled atmosphere (DCA) storage using RQ as the control parameter, provides a safer way to achieve lowest oxygen levels without negatively affecting fruit quality. Several studies have evaluated RQ-DCA on post-harvest storage of apple fruits and demonstrated high-quality maintenance and better aroma production after long-term storage. However, there are little/no findings regarding this technology and its effect on overall quality maintenance of 'Jonagold' apples. In this context, the objective of this study was to evaluate the effect of RQ-DCA, on quality attributes maintenance and aroma profile of 'Jonagold' apples and to compare this method to static CA.