Optimization of Deacidification of Degummed Palm Kernel Oil with Kolanut Pod Ash Using Response Surface Methodology

Abstract

Deacidification of crude palm kernel oil (CPKO) remains a critical challenge in developing countries, where conventional chemical refining methods are energy-intensive and economically prohibitive for small-scale processors. This study investigated the optimization of CPKO deacidification using kolanut pod ash as an eco-friendly bio-adsorbent through Response Surface Methodology (RSM) with Central Composite Design. Three process variables were evaluated: reaction time (10 - 30 minutes), temperature (60˚C - 70˚C), and kolanut pod ash dosage (1% - 5% w/w). There was 91% free fatty acid (FFA) content reduction. A significant quadratic model (F-value = 3.82, p = 0.0242) with Adjusted R 2 of 0.5718 was obtained. The influential factors were reaction time (p = 0.0111), kolanut pod ash dosage (p 2 /100g), acid values (7.18 - 51.02 mg KOH/g), and saponification values (250.67 - 290.12 mg KOH/g). This research demonstrates that kolanut pod ash can serve as an effective, low-cost, and green alternative to synthetic refining agents.