Process for preparing high-purity gardenia red

The invention discloses a process for preparing high-purity gardenia red. According to the process, gardenoside serves as the raw material; methyl ester bond hydrolysis is conducted under the action of alkaline or lipase/esterase; pH is adjusted by adding citric acid or inorganic acid, and carboxyl is formed under the acidic condition; beta-glucosidase hydrolysis is conducted under the appropriate condition; primary amine compounds are added under the deoxygenated condition, and a color reaction is conducted; then refining and drying are conducted, so that the high-purity gardenia red is obtained. The process comprises the following steps of conducting a hydrolysis reaction on methyl ester bonds, adjusting pH till the acidic environment is obtained, conducting a hydrolysis reaction on beta-glucosidase, conducting a color generation reaction, conducting separating purification, conducting drying and formation and conducting detection and verification. By means of the process, reaction time for preparing garden