PENINGKATAN KADAR ZINGIBERN DALAM MINYAK JAHE MENGGUNAKAN PENGKELAT ASAM OKSALAT DAN PENGUJIAN DENGAN SPECTROPHOTOMETER VISIBLE (Increasing Zingibern Content in Ginger Oil with Oxalic Acid as Chelating Agent and Testing by Visible Spectrophotometer)

Abstract

Ginger oil from steam distillation process has low zingibern content because it has not been removed from impurities and complex compounds. Therefore, chelating method is used which serves to improve the quality of ginger oil. Chelating method in this study is liquid-liquid extraction of ginger oil using oxalic acid. (Hernani, 2006). The measurement of zingibern using visible spectrophotometry. The increase of zingibern content with chelating of oxalic acid was obtained with the equation y = 0,662x + 4,091 and R² = 0,974, obtained the value of increasing levels of zingibern getting smaller. The increasing zingibern content by chelating the Oxalic Acid, where the concentration of Oxalic Acid are 0N; 0.5N; 1N; 1.5N; 2N; 2.5N and 3N the result are 4,284; 5,509; 5,764; 6,558; 7,205; 7,735 and 8,147. In this experiment, the value of RSD for the concentration 0N is 0,408%, the concentration of 0.5N is 0,391%, the concentration of 1N is 0%, the concentration of 1.5N is 0,408%, the concrentration of 2N is 0 %, the concentration of 2,5N is 0.408% and concentration of 3N is 0.408%. Good precision if the RSD value is less than 2%. Increased levels of zingibern with chelating Oxalic Acid according to the equation y = 0.623x + 3.961 and R² = 0.979 Keywords: Oxalic Acid, Essential Oil, Ginger, Zingibern and Visible Spectrophotom