Study on the effect of intermittent microwave drying conditions on the bioactive compounds and antioxidant capacity of beetroots

The object of this research was the beetroots prepared by intermittent microwave drying at different conditions. paper aimed to investigate influence conditions (power density, gap ratio and slice thickness) on bioactive compounds antioxidant capacity beetroots. A system SAM-255 (CEM Corporation, USA) used fresh effect power densities (1.0, 1.5, 2.0, 2.5 W/g), ratios (1, 2, 3, 4) thicknesses (2, 4, 6, 8 mm) were investigated. Colorimetric methods determine contents betalains, total phenolic flavonoid, dried ascorbic acid content determined using 2,6-dichloroindophenol titration method. Results showed that thickness significantly affected time, time decreased with increasing while increased growth ratio. shortest (35.4±2.6 min) occurred 2. betacyanins found be highest in 2 mm. 4 mm content. Moreover, (240.00±2.32 mg/100 g) flavonoid (14.52±0.06 mg rutin equivalent (RE)/g) appeared density 2.0 W/g, (12.54±0.13 gallic (GAE)/g) 6 For beetroots, 1,1-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity reached value 6.43±0.03 trolox (TE)/g W/g. While values ferric-reducing (FRAP) (15.47±0.10 TE/g) 2,2′-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) (25.31±0.30 It ABTS ability FRAP related presence reductions including acid, most effective condition for mm, leads a better preservation high capacity.