Effect of catalytic infrared radiation drying parameters on drying kinetics, bioactive compounds, and functional properties of cactus pear cladodes

• CIR drying reduced the drying time from 660–972 min to 60–110 min. • Page model is best for modeling the drying of cactus cladode slices using CIR. • The LP gas supply pressure on drying process alters biocompounds in cladode slices. • CIR emitter distance affects antioxidant and digestive enzyme inhibition capacity. The influence of catalytic infrared radiation (CIR) on drying characteristics, biocompounds, and functional properties of cactus pear cladode slices (CPCS) was evaluated. Two experiments were conducted. Experiment I varied the LP (liquefied petroleum) gas supply pressure (LPGSP) from 70 to 110 mbar at a 38.0 cm-fixed distance between the emitter and the CPCS. Experiment II varied the distance between CPCS and CIR-emitter at 50 mbar of LPGSP. The Page's model showed the best fit (R²=0.99) to describe the drying kinetics. In Experiment I, 80 mbar gas supply pressure and 70 min of drying (2615.51 ± 9.65 W/m²) was the best condition, with higher non-digestible carbohydrates content. Meanwhile, scavenging of ABTS and DPPH were higher at 100 or 110 mbar. In Experiment II, the best distance between CPCS and CIR-emitter was set at 14.0 cm, however, phytochemical losses were observed. Non-digestible carbohydrates, condensed tannins (5.7 mg CAE/g), and saponins (5.0 µg OAE/g) were higher at 24.0 cm, while carotenoids where enhanced at 38.0 cm. Furthermore, 14.0 and 38.0 cm had the highest DPPH and α -amylase, and ABTS and pancreatic lipase inhibition, respectively. The exploratory results establish a foundation for optimization of CIR technology in drying processes, as a promising alternative to reduce drying time while maintaining functional properties, which are essential for human health. Future perspectives include scaling up CIR technology for industrial applications, as it offers significant opportunities to enhance energy efficiency, reduce post-harvest waste, and contribute to food security and sustainability in the agri-food sector.