Gardenia blue pigment with high brightness and low redness and preparation method thereof

The invention discloses a gardenia blue pigment with high brightness and low redness and a preparation method thereof, and belongs to the technical field of pigment extraction. The preparation method comprises the following steps: by taking a gardenia extract enzymolysis product genipin as a raw material, weighing genipin and amino acid (phenylalanine, tryptophan, glycine or tyrosine) in a molar ratio of 1: (0.375-0.75), and carrying out polymerization reaction under conventional conditions to generate a gardenia blue precursor; the gardenia blue precursor is subjected to oxidation color generation and ultrafiltration membrane refining, and finally spray drying is performed to obtain the gardenia blue pigment which is high in brightness, low in redness and low in cost. 本发明公开了一种高亮度、低红度的栀子蓝色素及其制备方法，属于色素提取技术领域。以栀子提取物酶解产物京尼平为原料，称取摩尔比为1:(0.375～0.75)京尼平与氨基酸(苯丙氨酸、色氨酸、甘氨酸或酪氨酸)，在常规条件下发生聚合反应生成栀子蓝前体；栀子蓝前体再进行氧化呈色和超滤膜精制，最后经过喷雾干燥，得到亮度高、低红度及低成本的栀子蓝色素。