| 摘要 |
PURPOSE: A method for preparing a natural anthocyanin dye is provided, to obtain an anthocyanin dye showing a color similar to a natural color and capable of being used to dye various materials comprising plastic, metals and stone. CONSTITUTION: The method comprises the steps of cutting blueberry into a size of about 2 mm; adding the cut one to an extraction solvent and stirring the solution with 100-300 rpm at a pH of 2-10 and a temperature 30-60 deg.C for about 12-24 hours; centrifuging the obtained extract to remove insoluble solid components; removing polymer materials such as starch by using hollow fiber with MWCO of 10,000 Dalton; removing components of low molecular weight such as water by using UF/MF; concentrating the obtained dye concentrate by using a vacuum evaporator at 50 deg.C; and drying the concentrated one by using a spray dryer at 110 deg.C to prepare the powder with a size of 100-200 micrometers. At least one selected from the group consisting of a blueberry, a cherry, a mulberry, Phytolacca esculenta, a beet and a red sweet potato can be used instead of a blueberry. |
