Preparation method of high-color-value water gardenia yellow pigment

The invention discloses a preparation method of high-color-value water gardenia yellow pigment, which comprises the following steps: selecting fresh and mature water gardenia fruits, crushing until the granularity is about 0-2mm, adding 10-15 times by mass of cold water, extracting for 1-2 days at room temperature, repeating for 2-3 times, performing suction filtration by using silica gel at room temperature to remove impurities in the extract liquid, and drying to obtain the high-color-value water gardenia yellow pigment. By adopting a macroporous resin refining method, byproducts such as colorless geniposide and chlorogenic acid are separated, and the high-color-value water gardenia yellow pigment is obtained. The macroporous resin is preferably LSA-10 type macroporous resin with high adsorption rate and high desorption rate, performing rotary evaporation on a pigment solution purified by the macroporous resin through a vacuum rotary evaporator to obtain a concentrated solution, and finally performing vacuu