Drying Performance of Monkey Cola: Comparative Analysis of Ripe and Unripe Samples at Different Thicknesses and Temperatures
A. F. Ogunnaike *
Department of Agricultural and Bio-Environmental Engineering, The Federal Polytechnic, Ado-Ekiti, Nigeria.
O. A. Oyedele
Department of Agricultural and Bio-Environmental Engineering, The Federal Polytechnic, Ado-Ekiti, Nigeria.
O. C. Adeosun
Department of Agricultural and Bio-Environmental Engineering, The Federal Polytechnic, Ado-Ekiti, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Aims: This study examined the influence of slice thickness and drying temperature on the drying kinetics of ripe and unripe monkey cola (Cola lepidota) under hot‑air drying conditions.
Study Design: An experimental design was used for this study.
Place and Duration of Study: Department of Agricultural and Environmental Engineering, Ado Ekiti, Ekiti State, Nigeria, December 2024 and October 2025.
Methodology: Samples were prepared in three thicknesses (T1, T2, T3) and dried at 40 °C and 50 °C using a tray dryer. Moisture content reduction was monitored over time, and drying rate curves were generated to evaluate the effects of thickness and temperature.
Results: Results showed that thinner slices (T1) consistently exhibited higher drying rates, while thicker slices (T3) retained moisture longer. Increasing temperature from 40 °C to 50 °C significantly enhanced drying efficiency across all thicknesses. Ripe monkey cola dried faster than unripe samples, attributed to softer tissue structure and higher free water content, whereas unripe samples showed slower drying due to denser tissue and higher bound water content. Regression models (polynomial and exponential) fitted the drying data with high accuracy (R² > 0.85), confirming predictable drying behavior.
Conclusion: These findings highlight the importance of optimizing slice thickness and drying temperature to achieve efficient moisture removal while preserving product quality.
Keywords: Monkey cola, drying kinetics, slice thickness, drying temperature, tray dryer