Optimisation of Microwave-Assisted Extraction of Antioxidant Activity from Pandanus amaryllifolius Leaf and Evaluation of Blending Properties in Refined Bleached Deodorised Palm Olein Through Response Surface Methodology

Abstract

The demand for natural antioxidants in the food industry has steadily increased due to growing consumer awareness of the health benefits associated with consuming antioxidant-rich foods. Plant-based antioxidants offer a promising alternative to synthetic antioxidants, as they are perceived as safer and more sustainable. Pandan (Pandanus Amaryllifolius) leaves, have been recognised for their high antioxidant activity attributed to their rich phenolic content. Microwave-Assisted Extraction (MAE) has emerged as a green and efficient extraction technique for obtaining bioactive compounds from plant materials. This study aims to improve the extraction parameter of MAE for obtaining high antioxidant activity from P.amaryllifolius and to determine the optimal blending ratio and frying cycle of P.amaryllifolius as a natural antioxidant in Refined, Bleached and Deodorised (RBD) palm olein. The variables examined were the extraction power (350–450 W), extraction temperature (70–88℃) and extraction time (10–20 min), which are crucial factors affecting the extraction efficiency(yield) and antioxidant activity of P.amaryllifolius. The antioxidant activity of P.amaryllifolius was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and yields were measured. The total yield varied from 12.32 to 21.63% while antioxidant activity varied between 86.7 to 96.6%. Results revealed that the optimal extraction conditions for high yield and antioxidant activity were 450 W, 20 min, and 70℃. Under ideal conditions, the equivalent yield and antioxidant activity values were 20.54% and 92.4%, respectively. Additionally, moisture content and free fatty acid measurements were performed to determine the optimal mixing ratio and frying time of P.amaryllifolius in RBD palm olein. RBD palm olein containing 0.4% P.amaryllifolius demonstrated the most encouraging result with the highest four cycles of frying. In conclusion, optimising the extraction parameters of P.amaryllifolius using MAE provides valuable experimental data that can guide the formulation of natural antioxidant additives for enhancing the oxidative stability of food products, particularly those containing palm olein as a major ingredient.