Evaluation of Late-Maturing Peach and Nectarine Fruit Quality by Chemical, Physical, and Sensory Determinations

Abstract

In this work both analytical and sensory determinations were carried out to evaluate quality of yellow (Summerset, Tardiva 2000, Fairtime, Guglielmina) and white flesh (Daniela) late-ripening peach and nectarine (California and Fairlane) cultivars. Analytical measurements included weight, diameter, soluble solid content, titratable acidity, pH, and peel color. To describe and quantify the peach and nectarine sensory profile a panel of 10 judges generated 15 descriptors. According to univariate analysis of fruit quality attributes, 'Fairtime', 'Summerset', 'Daniela' and 'California' produced large and attractive fruits with extensive red peel color. On the other hand, 'Guglielmina', 'Daniela', 'Tardiva 2000' and 'Fairlane' produced superior quality fruit in terms of soluble solids, titratable acidity, sweetness, and flavor. The white flesh peach 'Daniela' produced fruits with the best balance between external and internal quality. Cluster analysis on standardized component coordinates from Biplot analysis allowed for the identification of two main groups. One group included 'Daniela', 'Guglielmina', 'Tardiva 2000' and 'Fairlane' along with attributes more indicative of ripe fruit such as soluble solids, sweetness, sugar/acid, juiciness, ground color index, peel color uniformity, flesh color intensity, mealiness, peach odor and flavor, flower odor and flavor. The other group included 'Summerset', 'Fairtime' and 'California' along with weight, diameter, consistency, flesh firmness, percentage of cover color, bitterness, titratable acidity, sour and grassy odor and flavor. The dual approach adopted in this study indicates that cultivars with large and attractive fruits are often lacking real eating quality. This poses serious doubts on the real value of exterior appearance for recognizing high quality peaches and nectarines.