Optimization of the ethanol extraction process of the gingerol from ginger

This study aimed to optimize the gingerol extraction process of ginger for improving the gingerol yield by the ethanol.Four technological factors which affected the gingerol yield were sifted and optimized by Plackett-Burman ( PB) and Central Composite Design ( CCD) . Based on those, the prediction model of gingerol yield was determined and validated. The results showed that the three key factors which influenced the yield of gingerol were the solid-liquid ratio, extraction temperature and ethanol concentration. The impregnation time had little influence on the gingerol yield. The prediction model which were established by the CCD had a highly significant correlation ( p < 0.0001) and the determination coefficient ( R²) was 0.96.There had a strong interaction between the solid-liquid ratio and ethanol concentration.The optimal technological condition was that the solid-liquid ratio, extraction temperature and ethanol concentration were 1 ∶ 57 g/m L, 54 ℃, and 72%, respectively. The prediction value of gingerol yield was 0.98%, compared with the measured value 0.94%, the deviation was only 4.10%. It indicates that optimizing the ethanol extraction technology of the gingerol by response surface analysis is reliable.This result can provide an important reference for the further exploitation of the gingerol.