Segregation of apple cultivars on the basis of main fruit physical and chemical properties and antioxidant activity

Abstract

This study aims to analyze the essential physicochemical properties and antioxidant activity of 25 apple commercial cultivars grown in Serbia during 2019 and 2020 in order to segregate the apples with the best size, shape, and also nutritious and health promoting values. The results showed that ‘Morens Jonagored’ and ‘Red Boscop’ had similar and the highest fruit weight (FW) whereas ‘Golden Delicious’, ‘Hired’, ‘Red Chief ’, and ‘Morens Jonagored’ had the highest and similar fruit length (L). The lowest both these values were found in ‘Akane’. ‘Red Boscop’ had the highest fruit diameter (D), whereas the lowest had ‘Galaxy’. Twenty-two or 88% of the examined cultivars have a D greater than 70 mm. Both fruit shape indexes [sphericity (φ) and aspect ratio (Ra)] were the highest and similar in ‘Akane’ and ‘Budimka’ and the lowest in ‘Red Chief ’. Peel was a better source of dry matter (DM), total phenolic content (TPC), and total flavonoid content (TFC) and had higher antioxidant capacity than flesh. Moroever, pH juice was higher in peel. In contrast, titratable acidity (TA) was higher in flesh in comparison with peel, whereas ash content was statistically similar in both peel and flesh tissues. ‘Akane’ had the highest total anthocyanin content (TAc), whereas the lowest was found in ‘Red Boscop’. Old cultivar ‘Budimka’ had the highest TPC and TFC in both peel and flesh, whereas ‘Ginger Gold’ had the lowest TPC and TFC and also the lowest antioxidant power. Peel of ‘Red Chief ’ and flesh of ‘Braeburn’ had the best antioxidant activity. Among others, correlation analysis showed that the DM content in the peel is a crucial factor that determines the DM, soluble solids content (SSC), TPC, TFC, and DPPH free-radical scavenging activity values in the flesh. The principal component analysis (PCA) showed high discrimination capabilities of variables measured and revealed that a more nutritious peel may be darker or redder while a more nutritious flesh may have a lighter color and lower SSC.