A Survey of Fruit Quality Characteristics of Georgia Peach (Prunus persica L.) Cultivars

Fresh peach fruit consumption per capita in the United States has been in decline from 6.0lb in 1990-1992 to 4.4lb in 2010-2012. This reduction has been frequently associated with consumer disapproval of peach fruit quality. On the other hand, increase in consumer acceptance has been often linked to variations in textural characteristics, soluble solid content (SSC), total titratable acidity (TTA), SSC/TTA ratio, phenolics, and aroma volatiles. The main objective of this research was to study a representative group of peach varieties grown in Georgia for fruit quality characteristics: SSC, TTA, sugar and acid profiles. Commercially ripe peaches of various cultivars were harvested, maintained for 4-5 days at room temperature (21 ± 1°C), and then frozen for further analyses. Instrumental analyses of fruit were performed by the Agricultural and Environmental Services Laboratories at the University of Georgia, Athens, GA. Significant differences between varieties were found for the majority of variables being measured (P<0.05). Among varieties, SSC values ranged from 8.2 to 13.0 for ‘Springprince’ and ‘Gala’, respectively. Similarly, total sugars ranged from 14.9 to 40.2 mg/g for ‘Blazeprince’ and ‘Early August Prince’, respectively. Within the sugars, sucrose levels ranged from 10.3 for ‘Blazeprince’ to 32.4 mg/g for ‘Gala.’ Several acids were measured and identified, with citric acid having the highest value of 3.4 mg/g for ‘Flavorich’ cultivar. Among the identified acids, succinic, tartaric, and malic acids had slightly lower concentrations than citric acid, with an average range of 0.5 to 1.3 mg/g. Total acid values ranged from 4.2 for ‘Blazeprince’ to 34.1 mg/g for ‘Redglobe.’ ‘Blazeprince’ cultivar had the lowest concentration for total sugars and total acids among all varieties. Inversely, the highest sucrose and total sugar concentrations were found in ‘Early August Prince’ and ‘Gala’ varieties. The results of these analyses will be used to identify fruit characteristics that are important in fresh peaches. Additionally, the peach cultivars will be compared in the future using sensory analysis (both descriptive and consumer tests) to determine the effect of these fruit quality characteristics and their relationship with consumer acceptance.