Optimization and scale-up process for supercritical fluids extraction of ginger oil from Zingiber officinale var. Amarum

Optimization process for supercritical fluid extraction (SCFE) of ginger oil was performed on a laboratory scale apparatus (2 x 1 L extraction vessel) using Taguchi's orthogonal array method. Effects of extraction pressure, extraction temperature and carbon dioxide (CO2) flow rate on extraction yield and 6-gingerol content in ginger oil were investigated at levels ranging between 10 and 15 MPa, 35-45 degrees C and 10-20 g/min, respectively. The results were compared to those obtained by high pressure Soxhlet extraction with liquid CO2, Soxhlet extraction with n-hexane, and percolation with ethanol (96%). The optimum conditions for the highest oil yield (3.10%) and highest content of 6-gingerol in ginger oil extract (20.69%) were obtained using SCFE at 15 MPa, 35 degrees C and 15 g/min. The experimental oil yield and 6-gingerol content at optimum conditions were in accordance to the values predicted by computational process. Based on optimization process results, scaling-up process to a commercial scale apparatus (2 x 50 L extraction vessel) were performed by constantly maintaining solvent-to-feed (SF) ratio. At the optimum conditions, SCFE of ginger oil was successfully scaled-up by fifty-folds with higher oil yield (3.83%) and lower 6-gingerol content (18.00%). (C) 2016 Elsevier B.V. All rights reserved.