Peaches, nectarines, and plums are among the most popular and valuable stone fruits from the Rosaceae family. Their fruit are rich in bioactive compounds, including flavonoids, anthocyanins, carotenoids, phenolic compounds, vitamins, and antioxidants. In this study, the chemical attributes, bioactive compound content, and antioxidant activity of 18 peach cultivars (‘UFOne’, ‘UFGlo’, ‘UFBeauty’, ‘UFSun’, ‘Flordaprince’, ‘Gulfcrismon’, ‘UFBlaze’, ‘TropicSnow’, ‘TropicBeauty’, ‘UFGem’, ‘UFBest’, ‘Flordaglo’, ‘Flordabest’, ‘UFO’, ‘Flordaking’, ‘Flordacrest’, ‘UFSharp’, and ‘Flordabelle’), four nectarine cultivars(‘UFRoyal’, ‘Sunraycer’, ‘Sunmist’, and ‘Sunbest’), and four plum cultivars (‘Gulfrose’, ‘Gulfgold’, ‘Gulfblaze’, and ‘Scarlet Beauty’) were evaluated. Total soluble solids (TSS), titratable acidity (TA), TSS/TA ratio, and juice pH presented significant variations among cultivars. The highest TSS content was recorded in ‘Sunmist’ nectarine, while plum cultivars had the highest TA levels, particularly ‘Scarlet Beauty’. The TSS/TA ratio was highest in ‘UFSun’ peach. ‘Gulfrose’ plum showed the highest total anthocyanin concentration (TAC) level. Total phenolic content (TPC) varied significantly, with plum cultivars, particularly ‘Scarlet Beauty’, having the highest amount. Similarly, total antioxidant activity (TAA) was highest in ‘Scarlet Beauty’ and ‘Gulfrose’ plums, while ‘TropicSnow’ peach and ‘SunBest’ nectarine had the lowest TAA. Multivariate statistical analyses revealed clear separations among cultivars based on chemical and bioactive parameters. These findings provide valuable insights into the biochemical diversity of peach, nectarine, and plum cultivars, emphasizing the superior bioactive and antioxidant properties of plum cultivars.
