The impact of fixed wave application time on the physicochemical and microstructural characteristics of potato slices during intermittent infrared–hot air drying

Intermittent infrared–hot air (IR–HA) drying has emerged as an advanced method to enhance drying efficiency. This study investigated the impact of pulse ratio (PR) with constant wave application time on drying potato slices using this hybrid technique. Process variables included IR power (0 W (HA only), 300 W, 600 W, 900 W) and PR (1 (continuous), 2, 3, 4), assessing their impact on the physicochemical and microstructural characteristics. Results revealed that drying time reduced significantly with increased IR power (300–900 W) and decreased PR (4–1). D eff rose with higher power and continuous mode due to enhanced internal vapor pressure. Compared to HA drying, the hybrid method yielded lower shrinkage, bulk density, and energy consumption. Potatoes dried at 900 W and PR 4 presented minimal shrinkage, maximal rehydration, and preserved microstructure, while the highest energy efficiency occurred at 900 W and PR 1. These results suggest that adjusting IR power and PR can balance energy efficiency and product quality, offering an adaptable framework for industrial drying operations. Intermittent IR–HA drying yields structurally and functionally superior dried products, supporting its use in energy-conscious food processing. This study also presents a streamlined alternative to complex variable-pulsing systems, ensuring industrial applicability without compromising precision. • Joint infrared – hot-air drying was used to produce high-quality fat-free potato chips. • The hybrid method outperformed hot-air drying, yielding higher porosity and energy efficiency. • Samples at 900 W and pulse ratio 4 exhibited minimal shrinkage, maximal rehydration, and preserved microstructure. • The novelty lies in optimizing pulse ratios with constant application time, demonstrating its potential to enhance product quality. • The findings offer a sustainable approach to improve potato drying processes by balancing efficiency and quality.