Characterization of Royal Gala apple aroma using electronic nose technology-potential maturity indicator

Changes in aroma of apple harvested at four different maturities were measu red at harvest and after short-term storage using electronic aroma sensors ("electronic nose") and classical headspace/gas chromatography methods. Sto red fruits were also evaluated by a trained sensory panel. Compared with he adspace/gas chromatography, the electronic nose was found to be more sensit ive (similar to 40 times) in terms of sample size. The sampling procedure f or the electronic nose was much less complex. Using discriminant function a nalysis, both methods classified the apples tested into groups according to harvest date. After storage, the groupings were more diffuse. Results from sensory testing showed partial separation along the first linear discrimin ant but did not classify the apple into distinct groups. Important differen ces between treatments were found for "overall flavor", "acid flavor" inten sity, "crispness", "cider/fernented aroma", "vegetative aroma"; and "canned pear aroma".