Effects of different drying methods on the quality characteristics of nero and viking aronia (Aronia melanocarpa) cultivars of fruits

This study aimed to determine the effects and the drying method that provided the highest quality of four drying methods (room drying (RD), vacuum drying (VD), freeze drying (FD) and hot air drying (HAD) (55°C, 65°C and 75°C) on the quality of organic aronia fruits of 'Nero' and 'Viking' varieties grown under organic farming conditions in Yalova/Güneyköy. The fruits harvested at commercial harvest time were brought to the IUAS, Faculty of Agriculture, and stored (0°C, 90±5% RH) until applications were made. Water activity (WA), total dry matter (TDM), total phenolic content (TPC), total flavonoid content (TFLC), antioxidant activity (AA), ash, external and internal fruit color L* a*, b*, C, h° and ΔE*, soluble solid content (SSC), titratable acidity (TA), SSC/TA, pH, rehydration capacity (RC), fruit width (FW) and length (FL), sensory (external appearance (EA), taste-aroma (TAR), texture and odor) analyses were performed. WA was changed between 0.301-0.411 in 'Nero', and between 0.324-0379 aw in 'Viking'; TDM was changed between %91.42-97.25 in 'Nero', and between %92.46-96.73 in 'Viking'; the highest TPC was in FD in 'Nero' and 'Viking' RD (888.67 and 843.01 mg gallic acid/100 g DM, respectively), the highest TFLC in 'Nero' HAD 75°C and 'Viking' RD (85.87 and 75.38 mg catechin/100g DM, respectively); the highest AA in 'Nero' and 'Viking' RD (98.32% and 98.53%, respectively); the highest ash in 'Nero' FD, 'Viking' HAD 55°C (33.30 and 29.62 g ash/kg dry product, respectively); the highest SSC/TA in 'Nero' HAD 65°C (31.30%) in 'Viking' RD (29.01%); in both varieties, the lowest RC, the best color, FW, FL, and sensory properties closest to fresh fruit were determined in FD.