NON-DESTRUCTIVE EVALUATION OF SWEET CHERRY (PRUNUS AVIUM L.) RIPENESS USING AN ELECTRONIC NOSE

The work is a preliminary study to verify the reliability of a commercial and portable electronic nose (PEN 2, Win Muster Airsense) as a tool to assess the differences among four sweet cherry cultivars and their ripening stages. Cluster Analysis was applied to maturity indices such as colour, titratable acidity, and total soluble solids in order to categorize sweet cherries into three clusters (ripening stages) referred to as “commercial ripe”, “ripe” and “over-ripe”. Principal Component Analysis applied to the electronic nose data highlighted the ability of the instrument to distinguish among cultivars and to assess the ripening stages of sweet cherries. From the Linear Discriminant Analysis, the electronic nose could effectively categorize fruit into the three ripening stages with the correct classification percentage of 95.0%. The predictive ability of Linear Discriminant Analysis classification model was confirmed by considering eight sweet cherries (two for each cultivar) analysed from postharvest to senescence.