Studies On The Extraction Optimization And Chermical Composition Analysis Of Pigment On Pitaya (Hylocereus Undatus) Fruit

The experiments were carried out by using the fruit of Hylocereus undatus fromZhangzhou city of Fujian province, studied the extraction optimization and chermicalcomposition analysis of pigment on pitaya （Hylocereus undatus） fruit,discussed theextractive stability and the influences of various additives to the stability of extractive. Thepurpose was to supply technical reference for processing in production and exploitation of redpigment from pitaya.The results were as follows:1With orthogonal experiment design, the results of the optimizating pigment extractionprocess showed that the best pitaya pulp extraction conditions were that the temperature30℃，the time45min，the proper extraction solvent was30%pure ethanol，pH was6.5.Under these optimum conditions, the content of betalains in extraction of Hylocereus is21.0mg of monomeric betanins per kg dry powder of pitaya pulp.2With orthogonal experiment design, the results of the optimizating pigment extractionprocess showed that the best pitaya peel extraction conditions were that the temperature30℃，the time45min，the proper extraction solvent was40%pure ethanol，pH was6.5.Under these optimum conditions,the content of betalains in extraction of Hylocereus is21.0mg of monomeric betanins per kg dry powder of pitaya peel.3The pigment in the pulp could be melt by tap water, distilled water,pure water. Thecolour of the pigment in the pulp was red. The best solvent was20%alcohol. OD value in themaximum absorption have small changes in the dark room-temperature after somet times.Pitaya pulp have the biggest OD value in the pH6.5.Light have the biggest effect on the OD value. OD value in the maximum absorptionhave small changes in the dark room-temperature after somet times. Na⁺and K⁺made thepigment deepen its color,but others mentals, such as Zn²⁺、Ca²⁺and Fe³⁺, made it fade. We cansee Na⁺and K⁺may raise its stability.But Zn²⁺、Ca²⁺and Fe³⁺decreased its stability It wasgood for stabilize by adding glucose,sugar,maltose and fructose to the pigment in thepulp.But adding starch would bad for its stabilize.Adding citric acid,ascorbic acid,sodiumsulfite,hydrogen peroxide and sodium benzoate to the pigment of the pulp, OD value in themaximum absorption would dropped.Among these changes, OD value in the sodium sulfiteand hydrogen peroxide had the biggest descender.The pigment in the peel could be melt by tap water,distilled water,pure water. The colourof the pigment in the peel was purplish red.The best solvent was20%alcohol. OD value in themaximum absorption have small changes in the dark room-temperature after somet times.OD value in the maximum absorption of the pigment from pitaya peel would not dropped in the pH values between5.0-6.0.Pitaya peel have the biggest value in the pH6.5.And pH between5.0-6.0pitaya peel havethe basically changes.Light have the biggest effect on the OD value. Na⁺and K⁺made thepigment deepen its color,but others mentals, such as Zn²⁺、Ca²⁺and Fe³⁺, made it fade. We cansee Na⁺and K⁺may raise its stability.But Zn²⁺、Ca²⁺and Fe³⁺decreased its stability. It wasgood for stabilize by adding glucose,sugar,maltose and fructose to the pigment in thepeel.But adding starch would bad for its stabilize.Adding citric acid,ascorbic acid,sodiumsulfite,hydrogen peroxide and sodium benzoate to the pigment of the peel, OD value in themaximum absorption would dropped.Among these changes, OD value in the sodium sulfiteand hydrogen peroxide had the biggest descender.4The pigments of pitaya were isolated and identified quickly by HPLC/MS. It isconcluded that the pigment of the pulp and the peel in pitaya from Fuzhou city of Fujianprovince were betalain not anthocyanin. Nine components in the pulp and there components inthe peel were isolated, respectively.