Effect of Citric Acid Addition at Anthocyanin Solubility of Red Color Melinjo Peels in Solvent Ethanol, Hehane and Petroleum Ether

摘要

The result from a research by Ermiziar, et al (2009) shows that the content of anthocyanin pigment in red colour melinjo peels with ethanol solvent is 10.87%. Anthocyanin structure which consists of Aromatic Hydrocarbons (Benzene) and the R groups that contain OCH_3 is a reason why anthocyanin can also be isolated with non-polar solvents. Nevertheless, the acid environment would be desirable to get more contains of anthocyanin and it can be more stable so it can be used as natural dyes. The research objectives are to isolate anthocyanin pigments using, Etanol, hexane solvent and Petroleum Ether (PE) and to determine the effect of using the citric acid 0.5% to the anthocyanin pigments which are produced by this research. The types of solvent that are used in this research are Etanol, Hexane and PE. The slices melinjo peels are macerated using etanol, hexane and PE, respectively for 24 hours and the separation of the solvent by means of rotary evaporator. The results were obtained the concentration of anthocyanin with ethanol solvent was 1200 ppm, hexane solvent was 0.864 ppm and PE solvent was 0.800 ppm by the addition of citric acid. Without the addition of citric acid, anthocyanin concentration was ethanol solvent was 4.000 ppm, hexane solvent was 0.634 ppm and PE solvent was 0.415 ppm.