Optimization of Ultrasonic Wave Extraction for Ginger Oleoresin Production (Zingiber officinale Roscoe) Using Response Surface Methodology (RSM)

The research aims to optimize extraction process of ginger oleoresin using ultrasonic wave. The variables observed include ratio of ginger to ethanol solvent (X-1), extraction temperature (X-2), and extraction time (X-3). The response surface method with central composite design (CCD) was used to obtain a mathematical model in order to define correlation between yield and refractive index of ginger oleoresin to any effected variables. The optimum conditions of ginger oleoresin using ultrasonic wave was obtained at composition ratio of ginger powder to ethanol X-1 at 1: 3.70 g g(-1), X-2 at 46 degrees C, and X-3 for 129 minutes generating 8.884% yield, and refractive index value at 1.487. A GC-MS analysis result shows that ginger oleoresin components in the best state consist of 41.65% volatile oil component and 26.2% carriers of spicy flavor. The ginger oleoresin produced in the research meets the EOA standard No. 243.