Studies On Stability And Application Of Natural Red Pigment From Chinese Herbaceous Peony Flowers

In this thesis, taking Chinese herbaceous peony flower(Paenoia lactiflora) as the experiment material,the technical conditions of extraction and chemistry character of red pigments were studied, respectively, the possible molecular structure of the pigment was discussed. According to the experimentation result, we will adopt chemistry method to protect the dried red flower stability.The processed were optimized using temperature, time, power, ratio of material/solvent as factors with extraction solvents by orthogonal test L16(45). The influencing effects of each factor was D>A>C>E>B, the optimum technical conditions of ultrasonic extraction was A1 B4 C4D4 E4, i.e. extraction temperature 70℃,power 250w, material/extractor ratio 1:50, extraction time 50min, the extraction solvent was 80% ethanol and hydrochloric acid solvent.The biggest absorbance wave length of Chinese herbaceous peony flower red pigment was 525nm. Their physicochemical properties, such as soluble property, stability to light, heat, oxidant, reducer and food additive are researched. The carbohydrate and the organic acid can enhance the color of the solvent. The oxidant and the reducer destroyed the pigment seriously. It can keep constant when the solution of ion Ca2+,Mg2+,Zn2+,Na+,K+,Pb2+, in contrast, the pigment could not keep constant when it mingled in the solution of ion Cu2+,Fe3+,Fe2+, which can make pigment solvent having deposition with turbid phenomenon.The TLC and LC\MS analyses are used to isolate anthocyanins and to determinate the molecular structure. The results showed that the red pigment is composed of two anthocyanins which are cyaniding-3-rutinosideand cyaniding-3,5-glucoside in bright red color and it can be used as an additive in natural.Result showed that the red pigment from the red flowers is very stable under acidic condition. The color protection technology of preventing the dried red flowers from fading could be applied to dried-flower industry. The dried red flowers whose color is similar to the fresh flowers could be obtained by treating the red flowers with different color protection solutions. According to the effect of color fixative on the preservation of the flower color, the order of the color fixative is:A3>A4>A1>A5>A2, and the effect of A3 is the best. The destroy of UV lighting on dried flower is more than natural lighting. The treatment on the dried flower by covering is not so remarkable.