The Effect of Canopy Position on the Fruit Quality Parameters and Contents of Bioactive Compounds and Minerals in ‘Braeburn’ Apples

Abstract

This study attempts to clarify the effect of canopy position on the physico-chemical parameters of apples cv. Braeburn. The experiments were carried out on fruit from the inner and outer part of the canopy in two growing seasons and at two harvest dates. Light measurements revealed that the average value of photo active radiation (PAR) for the inside and outside canopy amounted to 30.3 μmol/m2/s and 133.7 μmol/m2/s, respectively. Production year and canopy position significantly influenced ground color parameters a*, b*, C*, and h°, while the harvest date influenced all color parameters studied. For additional (red blush) coloration, the production year significantly influenced only the L* parameter, harvest date influenced all color parameters, and canopy position influenced L, a*, and C*. Only the fruits of the second harvest date showed more intense additional (red blush) coloration. The production year significantly affected fruit mass, firmness, total soluble solids (SSC), titratable acidity (TA), SSC/TA ratio, DPPH radical scavenging assay (AOP), total phenolic content (TPC), and total flavonoid content (TFC). The harvest date significantly influenced fruit mass, SSC, TA, SSC/TA, AOP, TPC, and TFC. The canopy position significantly influenced SSC, TA, AOP, TPC, and TFC. Regarding mineral content, the production year significantly affected the content of Fe, Ni, Cu, and Ca and the K/Ca ratio. The harvest date significantly affected Fe, Cu, Sr, K and K/Ca. The canopy position affected Fe, Ni, Zn, Sr, Ca, and K/Ca ratio, with a clear significant trend regarding the effect of canopy position only for Ca content (first and second year of the second harvest date) and K/Ca ratio (first year of both harvest dates). PCA analyses identified distinguishing features between apples, with differences defined specifically by AOP, TPC, TFC, Rb, Sr, Ca, and K/Ca on the PC 1 and Mn, Fe, Ni, Cu, and Zn on PC 2.