Resumen de Optimization of Bleaching Parameters in Refining Process of Kenaf Seed Oil with a Central Composite Design Model
Sook Chin Chew, Chin P. Tan, Kar Lin Nyam
Kenaf seed oil has been suggested to be used as nutritious edible oil due to its unique fatty acid composition and nutritional value. The objective of this study was to optimize the bleaching parameters of the chemical refining process for kenaf seed oil, namely concentration of bleaching earth (0.5 to 2.5% w/w), temperature (30 to 110 °C) and time (5 to 65 min) based on the responses of total oxidation value (TOTOX) and color reduction using response surface methodology. The results indicated that the corresponding response surface models were highly statistical significant (P< 0.0001) and sufficient to describe and predict TOTOX value and color reduction with R2of 0.9713 and 0.9388, respectively. The optimal parameters in the bleaching stage of kenaf seed oil were: 1.5% w/w of the concentration of bleaching earth, temperature of 70 °C, and time of 40 min. These optimum parameters produced bleached kenaf seed oil with TOTOX value of 8.09 and color reduction of 32.95%. There were no significant differences (P> 0.05) between experimental and predicted values, indicating the adequacy of the fitted models. There has been an increasing in the research focused on the application and development of crude kenaf seed oil into functional products, but the crude kenaf seed oil is still not edible. This study provides an optimization of the bleaching process in the chemical refining process, which can potentially expand to an industrial scale. The production of refined kenaf seed oil is advantageous in developing a diversity of health care products, functional foods, food supplements and cosmetic products.
