Retention of 6-Gingerol during Vacuum Drying of Ginger (Zingiber officionale R.) Slices

The demand for traditional herb medicine shows a tremendous increase. Anti-carcinogenic, antibacterial, antifungal, hypoglycemic, anti-atherosclerotic activity of medicinal ginger rhizome (Zingiber officionale R.) can be traced back to thousands of years. It is needed to improve the traditional methods of drying for better quality of dried ginger. Vacuum drying of Ginger slices was carried out at various drying conditions to study the effect of drying parameters on 6-gingerol content. High pressure liquid chromatography (HPLC) analysis was carried out to find out the maximum retention of the 6-gingerol in vacuum dried samples. In terms of quality, it was found that the product subjected to vacuum drying at 50 ⁰C and absolute pressure of 700 mm Hg had highest level of 6-gingerol retention compared to those samples of other drying conditions. Since the effect of different drying conditions on total 6-gingerol retention was found significant, vacuum drying at 50 C and 700 mm Hg was proposed as the most favorable condition for drying of ginger.