Studies on Drying Rate and characteristics of Babul Gum (Acacia nelotica)

Abstract

The present study aimed to investigate the drying kinetics and behaviour of Babul gum (Acacia nilotica) using a conventional tray dryer, in order to identify optimal drying conditions for improved shelf life and product quality. Fresh exudate gum samples were collected from the field in the form of grits, cleaned, and uniformly spread in a thin layer for drying. Drying was performed at four different temperatures (50°C, 60°C, 70°C, and 80°C) with a constant airflow rate of 1.5 m/s. Drying attributes such as moisture content, drying rate, moisture ratio, and drying time were measured and analysed. The drying process for all conditions occurred exclusively in the falling rate period, indicating moisture movement controlled by internal diffusion. The drying time decreased significantly with increasing temperature, ranging from 2165 minutes at 50°C to 3395 minutes at 80°C. Moisture loss followed a nonlinear trend, with the fastest reduction occurring in the early stages of drying. Sensory evaluation showed that samples dried at 70°C had superior texture, appearance, and overall acceptability, making them the most suitable for storage and value-added applications. Based on the results, conventional tray drying at 70°C is recommended for effective moisture removal while retaining product quality.