| Autor: |
Petković M; Department of Food Technology, Faculty of Agronomy Čačak, University of Kragujevac, Cara Dušana 34, 32000 Čačak, Serbia., Miletić N; Department of Food Technology, Faculty of Agronomy Čačak, University of Kragujevac, Cara Dušana 34, 32000 Čačak, Serbia., Pantelić V; Department of Food Technology, Faculty of Agronomy Čačak, University of Kragujevac, Cara Dušana 34, 32000 Čačak, Serbia., Filipović V; The Faculty of Technology Novi Sad, University of Novi Sad, Bulevar Cara Lazara 1, 21000 Novi Sad, Serbia., Lončar B; The Faculty of Technology Novi Sad, University of Novi Sad, Bulevar Cara Lazara 1, 21000 Novi Sad, Serbia., Mitrović O; Department for Fruit Processing Technology, Fruit Research Institute, Kralja Petra I 9, 32000 Čačak, Serbia. |
| Abstrakt: |
This study aimed to evaluate the effect of convective and microwave drying on the bioactive-compounds content of blackberry ( Rubus fruticosus ) fruits, as well as drying parameters and energy consumption. The fruit was dehydrated in a convective dehydrator at a temperature of 50 °C and 70 °C and in a microwave oven at power levels of 90 W, 180 W and 240 W. The highest amount of anthocyanins, polyphenols and antioxidant capacity were obtained in blackberry fruits that were microwave dried at 90 W and 180 W (46.3-52.5 and 51.8-83.5 mg 100 g -1 dm of total anthocyanins, 296.3-255.8 and 418.4-502.2 mg 100 g -1 dm of total phenolics, and 1.20-1.51 and 1.45-2.35 mmol TE 100 g -1 dm of antioxidant capacity for 90 W and 180 W models, respectively). It turned out that microwave dehydration shortened the processing time and lowered the energy consumption compared to convective drying (a significantly reduced drying time of 92-99% with microwave dehydration). Blackberry fruits dehydrated at 240 W showed the shortest dehydration time (59-67 min), minimal energy consumption (0.23 kWh) and the most efficient diffusion (1.48-1.66 × 10 -8 m 2 s -1 ). |
