Impact of two cold plasma pretreatments on the drying behavior, quality attributes, and hyperspectral response of barberry

This study investigated the influence of two cold plasma pretreatments dielectric barrier discharge (DBD) and gliding arc on drying kinetics, physicochemical attributes, and hyperspectral characteristics of barberry subjected to hot-air and microwave drying. Samples were exposed to DBD (3 and 6 min) or gliding arc (1 and 2 min) prior to drying. Plasma pretreatment induced microstructural modifications that facilitated moisture migration and shortened drying duration. The effective moisture diffusivity ranged from 6.88 × 10 − 8 to 1.01 × 10 − 7 m²/s for hot-air drying and from 7.90 × 10 − 6 to 9.73 × 10 − 6 m²/s for microwave drying. The highest diffusivity was observed for 6 min DBD combined with microwave drying, corresponding to a 23% increase relative to the untreated microwave control, while DBD increased diffusivity by approximately 3.7% under hot-air drying. Plasma treatment resulted in apparent increases in carbohydrate content and antioxidant activity, likely associated with enhanced extractability following structural disruption. In contrast, anthocyanin content decreased in all dried samples, particularly under more intensive plasma exposure. Microwave drying mitigated pigment degradation due to reduced exposure time, and 6 min DBD pretreatment reduced total drying time by 24% and 30% in hot-air and microwave drying, respectively. Hyperspectral imaging (400–1000 nm) coupled with chemometric modeling enabled accurate prediction of post-drying quality attributes ( R 2 > 0.90 ), with carbohydrates showing the highest predictive performance ( R 2 > 0.96 ). These findings demonstrate the potential of moderate DBD plasma pretreatment as an effective pre-drying approach for enhancing drying kinetics while preserving key quality parameters, and highlight hyperspectral imaging as a reliable non-destructive tool for quality monitoring.