Mesurement of aroma development during the ripening of Golden Delicious apples

In the frame of several research projects in apple breeding and conservation technology at the research station Agroscope Changins-Wädenswil ACW, key factors determining apple quality and the effect of different storage conditions on produce characteristics have been investigated. It is known that, besides classical quality parameters, such as firmness, sugar content and acidity, aroma is one of the most important factors affecting consumer acceptance of apples. In this study, a rapid and extensive analytical method for aroma profiling in apples is presented and its implementation as key tool for research purposes as well as for quality assurance discussed. The aroma production and development of Golden Delicious apples during ripening and storage was followed up with the SMart Nose®, an electronic nose based on mass spectrometry. Measurements of ripening parameters, such as ethylene production, firmness, sugar content and acidity, were also carried out and the results compared with the aroma analyses. The fingerprint data produced by the SMart Nose® showed good correlations with both firmness degradation patterns as well as with the ethylene production rates of the investigated apples.