Impact of cold plasma pretreatment and hybrid infrared—hot air drying on bioactive compounds, antioxidant activity, colorimetric attributes, and texture of red beet
Abstract
Drying is essential for food preservation, yet conventional methods often compromise product quality. This study investigated the effects of cold plasma pretreatment time (0, 15, and 30 s) and an intermittent infrared‐hot air hybrid dryer (300, 600, and 900 W; pulse ratios 1 and 2) on the functional and quality attributes of dried red beetroot. Cold plasma pretreatment significantly enhanced color attributes, with a 15 s exposure optimizing color intensity. While high infrared power (900 W) triggered pigment degradation, moderate power (600 W) improved brightness and color richness. Increased infrared power and pulse ratio 1 accelerated the drying process, thereby facilitating higher retention of total phenolics and antioxidant capacity. Texture profile analysis (TPA) revealed that specific conditions (15 s cold plasma pretreatment, 600 W power, and pulse ratio 1) significantly improved hardness and chewiness while reducing adhesiveness. The integration of cold plasma pretreatment with optimized intermittent infrared‐hot air drying effectively modulated the surface and internal structure of beetroot, ensuring a high‐quality dried product with enhanced functional and mechanical attributes.