Infrared drying of dill leaves: Drying characteristics, temperature distributions, performance analyses and colour...

Area of Science:

• Food Science
• Agricultural Engineering
• Thermodynamics

Background:

• Dill leaves require efficient drying methods to preserve quality.
• Infrared drying offers potential for rapid and effective food processing.

Purpose of the Study:

• To investigate the thin-layer drying behavior of dill leaves using infrared radiation.
• To determine the optimal infrared power intensity for drying dill leaves.

Main Methods:

• Drying experiments were conducted on dill leaves at three infrared power intensities (1790, 1970, and 2070 W/m²).
• The Diffusion Approach model was used to analyze drying kinetics.
• First and second law efficiencies were calculated.
• Total color change was measured to assess quality.

Main Results:

• The Diffusion Approach accurately modeled the drying behavior of dill leaves.
• Effective diffusivity values ranged from 6.84–8.96 × 10⁻⁹ m²/s.
• Higher power intensities increased drying efficiency (p < 0.05) but also maximized color change.
• The 1970 W/m² intensity offered the best balance between efficiency and quality.

Conclusions:

• Infrared drying is an effective method for processing dill leaves.
• The optimal infrared power intensity for drying dill leaves, balancing efficiency and quality, is 1970 W/m².